Publications by authors named "Mahmood Jeddi-Tehrani"

189 Publications

Does prior immunization with measles, mumps, and rubella vaccines contribute to the antibody response to COVID-19 antigens?

Iran J Immunol 2021 03;18(1):47-53

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Background: Incidence and severity of SARS-CoV2 infection are significantly lower in children and teenagers proposing that certain vaccines, routinely administered to neonates and children may provide cross-protection against this emerging infection.

Objective: To assess the cross-protection induced by prior measles, mumps and rubella (MMR) vaccinations against COVID-19.

Methods: The antibody responses to MMR and tetanus vaccines were determined in 53 patients affected with SARS-CoV2 infection and 52 age-matched healthy subjects. Serum levels of antibodies specific for NP and RBD of SARS-CoV2 were also determined in both groups of subjects with ELISA.

Results: Our results revealed significant differences in anti-NP (P<0.0001) and anti-RBD (P<0.0001) IgG levels between patients and healthy controls. While the levels of rubella- and mumps specific IgG were not different in the two groups of subjects, measles-specific IgG was significantly higher in patients (P<0.01). The serum titer of anti-tetanus antibody, however, was significantly lower in patients compared to healthy individuals (P<0.01).

Conclusion: Our findings suggest that measles vaccination triggers those B cells cross-reactive with SARS-CoV2 antigens leading to the production of increased levels of measles-specific antibody.
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http://dx.doi.org/10.22034/iji.2021.87990.1843DOI Listing
March 2021

A Novel Anti-HER2 Bispecific Antibody With Potent Tumor Inhibitory Effects and .

Front Immunol 2020 17;11:600883. Epub 2021 Feb 17.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Overexpression of HER2 has been reported in many types of cancer, making it a perfect candidate for targeted immunotherapy. The combination of two FDA approved monoclonal antibodies (mAbs), trastuzumab and pertuzumab, has more robust anti-tumor activity in patients with HER2-overexpressing breast cancer. We recently produced a new humanized anti-HER2 mAb, hersintuzumab, which recognizes a different epitope than trastuzumab and pertuzumab on HER2. This mAb, in combination with trastuzumab, exhibits more potent anti-tumor activity than each parental mAb alone. Here we have developed a novel bispecific anti-HER2 antibody (BsAb) designated as trasintuzumab, composed of trastuzumab and hersintuzumab, using dual variable domain immunoglobulin (DVD-Ig) technology. Both variable domains of trasintuzumab are fully functional and have similar affinities to the parental mAbs and are also able to bind to natural HER2 on the surface of several HER2-expressing cell lines. Trasintuzumab was found to inhibit the growth of different types of tumor cell lines through suppression of the AKT and ERK signaling pathways as efficiently as the combination of the parental mAbs. It also induced tumor regression as potently as the combination of the two mAbs in nude mice bearing ovarian and gastric cancer xenografts. Our data suggest that trasintuzumab may be a promising BsAb therapeutic candidate for the treatment of HER2-overexpressing cancers.
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http://dx.doi.org/10.3389/fimmu.2020.600883DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7927792PMC
February 2021

A novel tumor inhibitory hybridoma monoclonal antibody with dual specificity for HER3 and HER2.

Curr Res Transl Med 2021 Feb 24;69(2):103277. Epub 2021 Feb 24.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Electronic address:

Background: The human epidermal growth factor receptor (HER/ErbB) family-targeted therapies result in a significant improvement in cancer immunotherapy. Monoclonal antibodies (MAb) against HER2 demonstrated a survival benefit for patients; however, drug resistance unavoidably occurs due to the overexpression of HER3, which leads to treatment failure. Effective inhibition of HER3 besides HER2 is thought to be required to overcome resistance and enhance therapeutic efficacy.

Objective: The present study describes the production and characterization of a novel MAb, designated 1G5D2, which acts as a natural bispecific antibody targeting extracellular domains (ECD) of both HER2 and HER3.

Methods: In this study, 1G5D2 was produced by hybridoma technology against HER3-ECD, and its structural and functional characteristics were studied by various methodologies, including enzyme linked-immunosorbent assays, flow cytometry, immunoblotting, cell signaling, and cell proliferation assays.

Results: 1G5D2 specifically binds to both HER2 (subdomain III + IV) and HER3 (subdomain I + II) expressed on tumor cells, and these receptors compete with each other for binding to this MAb. Competition flow cytometry experiments demonstrated that 1G5D2 does not compete with heregulin and recognizes an epitope out of HER3 ligand-binding site. Evaluation of 1G5D2 inhibitory effects in tumor cell lines co-expressing HER2 and HER3 showed that 1G5D2 synergizes with trastuzumab to inhibit both PI3K/AKT and MAPK/ERK pathways and potently downregulates the proliferation of these tumor cells more efficiently than each MAb alone.

Conclusion: 1G5D2 is the first reported hybridoma antibody, which acts as a natural HER2/HER3 bispecific antibody. It might potentially be a suitable therapeutic candidate for HER2/HER3 overexpressing cancer types.
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http://dx.doi.org/10.1016/j.retram.2021.103277DOI Listing
February 2021

Culture density of menstrual blood-derived stromal/stem cells determines the quality of T cell responses: An experimental study.

Int J Reprod Biomed 2021 Jan 25;19(1):75-86. Epub 2021 Jan 25.

Reproductive Immunology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran.

Background: Menstrual blood-derived stromal/stem cells (MenSCs) are a new population of refreshing and highly proliferative stem cells. Immunomodulatory effects of MenSCs profoundly depend on their relative density.

Objective: To find whether MenSCs cultured at varying numbers would differentially affect the allogenic peripheral blood mononuclear cells (PBMCs) key features.

Materials And Methods: PBMCs were co-cultured with various MenSCs numbers. PBMCs proliferation was investigated via H-thymidine incorporation. Flow cytometry was used to assess human leukocyte antigen (HLA)-DR, HLA-ABC, HLA-G, and co-stimulatory markers on MenSCs and the percentage of regulatory T cells (Tregs) among PBMCs. The concentration of cytokines was determined in supernatant of co-cultures.

Results: The support of PBMCs proliferation at low MenSCs densities correlated with higher levels of pro-inflammatory interferon gamma (IFN-γ) in MenSCs/PBMCs co-culture and increased expression of HLA-DR by MenSCs. On the other hand, the suppressive property of MenSCs at higher densities was independent of Treg frequency, but correlated with a high concentration of Interleukin (IL)-6 and IL-10 in the co-cultures.

Conclusion: Totally, at different seeding densities, MenSCs could differentially interact with PBMCs leading to significant changes in the level of anti- and/or pro-inflammatory factors. These preliminary in vitro results are suggested to be taken into consideration in experimental models of MenSC-based immunomodulation. Nonetheless, for efficient utilization of MenSCs anti-inflammatory features in pre-clinical disease models, we still need to broaden our knowledge on MenSC-immune system cross-talk; this could play a part in designing more optimized MenSCs injection modalities in the case of future pre-clinical and subsequently clinical settings.
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http://dx.doi.org/10.18502/ijrm.v19i1.8182DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7851477PMC
January 2021

Potent synergistic anti-tumor activity of a novel humanized anti-HER2 antibody hersintuzumab in combination with trastuzumab in xenograft models.

Invest New Drugs 2021 Jun 3;39(3):697-704. Epub 2021 Jan 3.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Immunotherapy of HER2-overexpressing cancers by FDA approved monoclonal antibodies (mAbs) such as trastuzumab and pertuzumab has shown promising results. We have recently produced a novel humanized anti-HER2 mAb, hersintuzumab, which did not sterically inhibit binding of trastuzumab and pertuzumab to HER2, thus recognizing a distinct epitope on subdomain I + II of HER2. In this study, we assessed the in vitro and in vivo anti-tumor activity of this mAb individually and in combination with trastuzumab. Different HER2-overexpressing human cancer cell lines, including SKOV3, NCI-N87 HCC1954 and BT-474 were cultured and binding reactivity of Hersintuzumab to these cell lines was analyzed by flow cytometry. In addition, the inhibitory effect of different concentrations of hersintuzumab, trastuzumab and their combination on tumor cells growth was assessed by XTT assay. For Assessment of tumor growth inhibition in xenograft model, Balb/c athymic nude mice were subcutaneously injected with NCI-N87 and SKOV3 tumor cells and then treated intravenously with these mAbs. Our results showed that hersintuzumab could bind to all HER2-overexpressing cell lines similar to trastuzumab. In vitro experiments showed that both hersintuzumab and trastuzumab individually and in combination inhibited growth of all cell lines with the exception of HCC-1954.Inhibitory effect of the combination of mAbs was significantly higher than that of each mAb alone. Similar results were obtained in the gastric (NCI-N87) and ovarian (SKOV-3) tumor xenograft models. Hersintuzumab in combination with trastuzumab induces synergic anti-tumor effects on HER2-overexpressing cells in vitro and in vivo and is potentially a therapeutic tool for treatment of HER2-overexpressing cancers.
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http://dx.doi.org/10.1007/s10637-020-01048-4DOI Listing
June 2021

Immunoreactivity pattern of monoclonal antibodies against Hepatitis B vaccine with global Hepatitis B virus genotypes.

Clin Chim Acta 2020 Nov 15;510:203-210. Epub 2020 Jul 15.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran; Monoclonal Antibody Research Center, Avicenna Research Institute, ACECR, Tehran, Iran. Electronic address:

Hepatitis B surface antigen (HBsAg) specific monoclonal antibodies (mAbs) are potentially valuable therapeutic and diagnostic tool. We have previously established and characterized a panel of mAbs derived from immunized BALB/c mice with a yeast-derived recombinant HB vaccine subgentoype A2 and HBsAg subtype adw2. This study was conducted to evaluate the reactivity pattern of this anti-HBs mAbs panel with various genotypes and subgenotypes of HBV using the first WHO HBV genotype reference panel containing 15 serum samples representing the subgenotypes A1, A2, B1, B2, C2, D1-D3, E, F2, and H. Ten out of 21 anti-HBs mAbs were able to strongly recognize all gentopye/subtypes of HBsAg provided in the WHO reference panel. However, 10 out of 21 anti-HBs mAbs showed a moderate to profound loss of reactivity with HBV genotypes/HBsAg subtypes D2/ayw3, E/ayw4, F2/adw4, and H/adw4. Two mAbs from the second group displayed a profoundly reduced reactivity with only 1 out of 3 C2/adr genotype/subtype samples. The amino acid alignment of these 3 samples showed that this particular sample contains amino acid substitution at residue 127, which is located inside "a" determinant. This amino acid substitution, which profoundly affected the reactivity of anti-HBs antibodies, has been previously reported only in D/ayw3, E/ayw4, F/adw4, and H. Interestingly, the amino acid alignment of the samples in this WHO panel showed that P127T substitution can also be found in C2/adr. Comparing amino acids sequences inside the antigenic loop (AGL) showed that D2/ayw3 contains a T118A/P127T double substitution, E/ayw4 contains P127L/T140S, F2/adw4 contains P127L/T140S/ F158L, and H/adw4 contains P127L substitution. Therefore, amino acid variability at positions 118, 127, 140, and 158 was found to cause significant loss of reactivity with anti-HBs mAbs. Since HBsAg variability in different genotypes of HBV can profoundly affect the reactivity of anti-HBs mAbs, analytical sensitivity for HBsAg assays should be considered based on the circulating and common HBV variants in the relevant countries.
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http://dx.doi.org/10.1016/j.cca.2020.07.026DOI Listing
November 2020

Human immune response to salivary gland antigens in a leishmaniasis-endemic focus in Iran.

Pathog Glob Health 2020 09 9;114(6):323-332. Epub 2020 Jul 9.

Department of Medical Entomology and Vector Control, School of Public Health, Tehran University of Medical Sciences , Tehran, Iran.

Salivary proteins specific antibodies have been shown to be useful biomarkers of exposure to sand fly bites. This study aimed to investigate the level, duration, and dynamics of the human immune response against the SGL of  Parrot, 1917 (Diptera: Psychodidae), and to assess the immunoreactivity of human sera with SGL components in an endemic area of anthroponotic cutaneous leishmaniasis (ACL) in Iran. The study was carried out in 2-phase; longitudinal and cross-sectional. Sand flies were collected monthly from indoors and outdoors. In the longitudinal study, sera from healthy volunteers were collected monthly, and in the cross-sectional study, sera from healthy volunteers and patients with ACL lesion/s, were collected for immunoassay studies. The level of anti- saliva IgG was detected using the ELISA. Immunoreactivity of individual human sera with saliva components was also assessed by western blotting. was the predominant sand fly species in the study area. The maximum and minimum percentages of IgG responses were seen in October (66%) and March (29%), respectively. Additionally, the cross-sectional study showed that 59.3% of the healthy volunteers and 80% of the patients were IgG positive. The antibody response against  salivary gland was high during the sand fly active season and declined by the end of the activity of the vectors.  Antibody response against the SGL components of  was transient and individual-specific. Some individuals shared a strong reaction against certain individual antigens, which could be considered as vector exposure markers for further investigation.

List Of Abbreviations: ELISA: Enzyme-Linked Immunosorbent Assay; SDS PAGE: Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis; SGL: Salivary Gland Lysate; ACL: Anthroponotic Cutaneous Leishmaniasis; PBS: Phosphate Buffered Saline; BCA: Bicinchoninic Acid; PBS-T: Phosphate Buffered Saline Tween; FBS: Fetal Bovine Serum; HRP: Horseradish Peroxidase; TMB: 3,3',5,5'-Tetramethylbenzidine; PVDF: Polyvinylidene Difluoride; SGA: Salivary Gland Antigens; OD: Optical Density; KDa: Kilodalton; VL: Visceral Leishmaniasis; CL: Cutaneous Leishmaniasis; SGs: Salivary glands.
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http://dx.doi.org/10.1080/20477724.2020.1789399DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7480592PMC
September 2020

Peptide-Based Monoclonal Antibody Production Against SAG1 (P30) Protein of .

Monoclon Antib Immunodiagn Immunother 2020 Apr 27;39(2):51-56. Epub 2020 Mar 27.

Monoclonal Antibody Research Center, Avicenna Research Institute, ACECR, Tehran, Iran.

is an intracellular protozoan parasite that can infect a wide range of warm-blooded animals. Humans as an intermediate host are infected by ingesting infectious oocytes or tissue cysts, or passing through the placenta in pregnant women. The aim of this study is producing monoclonal antibodies against a synthetic peptide from (surface antigen 1 [SAG1] or P30) protein of . A synthetic peptide from SAG1 (P30) protein was conjugated to Keyhole Limpet Hemocyanin (KLH (and then used for immunization of two BALB/c mice. The produced antibody was purified by affinity chromatography and its specific interaction with the immunized peptide was then determined by enzyme-linked immunosorbent assay (ELISA). Immunoreactivity of the antibody was also tested by Western blot in cell lysate. The results show that the produced antibody has excellent reactivity with the immunizing peptide and also detects a single band of 30 kDa, which corresponds to SAG1 protein. This antibody can be used as a tool in different applications in research areas, including diagnosis, therapy, and infection inhibition.
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http://dx.doi.org/10.1089/mab.2019.0041DOI Listing
April 2020

Expression of Human Placenta-specific 1 (PLAC1) in CHO-K1 Cells.

Avicenna J Med Biotechnol 2020 Jan-Mar;12(1):24-31

Reproductive Immunology Research Center, Avicenna Research Institute, (ACECR), Tehran, Iran.

Background: Placenta-specific 1 (PLAC1), as a new Cancer/Testis Antigen (CTA), is frequently expressed in a variety of cancers and localized to cytoplasm and plasma membrane. Surface expression of cancer target antigens is of great importance that enables antibody-mediated cancer immunotherapy. The aim of the current study was to express the intact human PLAC1 protein on plasma membrane of a eukaryotic cell as a model for future anti-PLAC1-based cancer immunotherapy.

Methods: In the first approach, entire human PLAC1 gene including its own Signal Peptide (SP) was cloned into pIRES2-EGFP and LeGO-iG2 vectors and expressed in CHO-K1 cells. In the second approach, cytosolic and Signal-Anchor (SA) sequence of Transferrin Receptor Protein 1 (TFR1) were fused to extracellular portion of PLAC1 and expressed as above. Expression of PLAC1 was then assessed using Reverse Transcription Polymerase Chain Reaction (RT-PCR), Western Blot (WB), Immunocytochemistry (ICC), Immunofluorescence (IF) and Flow Cytometry (FC).

Results: The first approach resulted in the expression of PLAC1 in submembranous but not in the surface of transfected CHO-K1 cells. Using the chimeric human PLAC1 construct, the same intracellular expression pattern was observed.

Conclusion: These results indicated that there are some yet unknown PLAC1 localization signals employed by cancer cells for surface expression of PLAC1.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7035464PMC
March 2020

Inhibitory Effect of Polyclonal Antibodies Against HER3 Extracellular Subdomains on Breast Cancer Cell Lines.

Asian Pac J Cancer Prev 2020 Feb 1;21(2):439-447. Epub 2020 Feb 1.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Objective: Human epidermal growth factor receptor 3 (HER3) is a unique member of the tyrosine kinase receptors with an inactive kinase domain and is the preferable dimerization partner for HER2 which lead to potent tumorigenic signaling.

Methods: In this study, the expression plasmids coding for the human HER3 subdomains were transfected into CHO-K1 cells. Produced proteins were characterized by ELISA and SDS-PAGE. Rabbits were immunized and produced polyclonal antibodies (pAbs) that were characterized by ELISA, Immunoblotting and flowcytometry and their inhibitory effects were assessed by XTT on BT-474 and JIMT-1 breast cancer cell lines.

Result: The recombinant subdomains were highly immunogenic in rabbits. The pAbs reacted with the recombinant subdomains as well as commercial HER3 and the native receptor on tumor cell membranes and could significantly inhibit growth of Trastuzumab sensitive (BT-474) and resistant (JIMT-1) breast cancer cell lines in vitro.

Conclusion: It seems that HER3 extra cellular domains (ECD) induce a strong anti-tumor antibody response and may prove to be potentially useful for immunotherapeutic applications.
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http://dx.doi.org/10.31557/APJCP.2020.21.2.439DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7332115PMC
February 2020

Contribution of Fc fragment of monoclonal antibodies to tetanus toxin neutralization.

Neurotox Res 2020 Mar 13;37(3):578-586. Epub 2019 Nov 13.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Background: Monoclonal antibodies (MAbs) against neurotoxin of Clostridium tetani are considered as a novel source of immunoglobulins for passive immunotherapy of tetanus. Toxin neutralization is classically attributed to the Fab and F(ab')2 fragments of antibodies. Herein, we generated Fab and F(ab')2 fragments of three toxin neutralizing mouse MAbs and compared their neutralizing activities to those of their intact molecules.

Methods: Fab and F (ab')2 fragments of the antibodies were generated by papain and pepsin digestions, respectively, and their toxin neutralizing activities were compared with those of the intact antibodies in an in vivo toxin neutralization assay.

Results: While low doses of the intact MAbs were able to fully protect the mice against tetanus toxin, none of the mice which received Fab or F(ab')2 fragments survived until day 14, even at the highest administered dose. All mice receiving human polyclonal anti-tetanus immunoglobulin or their fragments were fully protected.

Conclusion: Reduction in toxin neutralization activities of Fab and F(ab')2 fragments of our MAbs seems to be influenced by their Fc regions. Steric hindrance of the Fc region on the receptor-binding site of the toxin may explain the stronger neutralization of the toxin by the intact MAbs in comparison to their fragments.
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http://dx.doi.org/10.1007/s12640-019-00124-9DOI Listing
March 2020

Epitope Mapping of Tetanus Toxin by Monoclonal Antibodies: Implication for Immunotherapy and Vaccine Design.

Neurotox Res 2020 Feb 13;37(2):239-249. Epub 2019 Aug 13.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Tetanus as a life-threatening disease is characterized by muscle spasm. The disease is caused by the neurotoxin of Clostridium tetani. Active form of tetanus neurotoxin is composed of the light chain (fragment A) and the heavy chain. Fragment A is a zinc metalloprotease, which cleaves the neuronal soluble N-ethylmaleimide-sensitive attachment receptor (SNARE) protein, leading to the blockade of inhibitory neurotransmitter release and subsequent generalized muscular spasm. Two functional domains of the heavy chain are fragment C, which is required for neuronal cell binding of the toxin and subsequent endocytosis into the vesicles, and fragment B, which is important for fragment A translocation across the vesicular membrane into the neuronal cytosol. Currently, polyclonal immunoglobulins against tetanus neurotoxin obtained from human plasma of hyper-immunized donors are utilized for passive immunotherapy of tetanus; however, these preparations have many disadvantages including high lot-to-lot heterogeneity, possibility of transmitting microbial agents, and the adverse reactions to the other proteins in the plasma. Neutralizing anti-tetanus neurotoxin monoclonal antibodies (MAbs) lack these drawbacks and could be considered as a suitable alternative for passive immunotherapy of tetanus. In this review, we provide an overview of the literature discussing epitope mapping of the published neutralizing MAbs against tetanus toxin.
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http://dx.doi.org/10.1007/s12640-019-00096-wDOI Listing
February 2020

PLAC1: biology and potential application in cancer immunotherapy.

Cancer Immunol Immunother 2019 Jul 5;68(7):1039-1058. Epub 2019 Jun 5.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Nafisi Building, Enghelab St., Tehran, 1417613151, Iran.

The emergence of immunotherapy has revolutionized medical oncology with unprecedented advances in cancer treatment over the past two decades. However, a major obstacle in cancer immunotherapy is identifying appropriate tumor-specific antigens to make targeted therapy achievable with fewer normal cells being impaired. The similarity between placentation and tumor development and growth has inspired many investigators to discover antigens for effective immunotherapy of cancers. Placenta-specific 1 (PLAC1) is one of the recently discovered placental antigens with limited normal tissue expression and fundamental roles in placental function and development. There is a growing body of evidence showing that PLAC1 is frequently activated in a wide variety of cancer types and promotes cancer progression. Based on the restricted expression of PLAC1 in testis, placenta and a wide variety of cancers, we have designated this molecule with new terminology, cancer-testis-placenta (CTP) antigen, a feature that PLAC1 shares with many other cancer testis antigens. Recent reports from our lab provide compelling evidence on the preferential expression of PLAC1 in prostate cancer and its potential utility in prostate cancer immunotherapy. PLAC1 may be regarded as a potential CTP antigen for targeted cancer immunotherapy based on the available data on its promoting function in cancer development and also its expression in cancers of different histological origin. In this review, we will summarize current data on PLAC1 with emphasis on its association with cancer development and immunotherapy.
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http://dx.doi.org/10.1007/s00262-019-02350-8DOI Listing
July 2019

Development of a Novel Inhibitory Chimeric Anti-HER2 Monoclonal Antibody.

Iran J Immunol 2019 Mar;16(1):26-42

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Background: We have recently produced an inhibitory mouse anti-human HER2 mAb (2A8) which displayed potent anti-tumor activity in combination with trastuzumab.

Objective: To describe chimerization and functional characterization of 2A8 mAb.

Methods: The VH and VL genes of 2A8 mAb were amplified from cDNA of the mouse hybridoma, ligated to constant regions of human immunoglobulin, and expressed in CHO cell line. Reactivity with four members of human HER family, the inhibitory effects and antibody-dependent cell cytotoxicity (ADCC) of purified chimeric mAb (c2A8) were assessed by ELISA, XTT, H3-tymidine incorporation and lactate dehydrogenase assays. Inhibition of ERK and AKT downstream signaling pathways by the chimeric antibody were analyzed by Western blotting.

Results: Chimeric 2A8 mAb bound to recombinant human HER2 and did not cross-react with the other members of HER family. Moreover, c2A8 was able to recognize HER2-overexpressing cancer cell line and inhibited growth and proliferation of these cells. The binding affinity of c2A8 was comparable to the mouse parental mAb. ADCC and Western blotting results showed that the mouse 2A8 mAb was successfully chimerized and could significantly inhibit phosphorylation of AKT in combination with trastuzumab.

Conclusion: The c2A8 mAb is potentially a valuable tool for targeted immunotherapy of HER2 positive cancers.
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http://dx.doi.org/10.22034/IJI.2019.39404DOI Listing
March 2019

Characterization of Monoclonal and Polyclonal Antibodies Recognizing Prostate Specific Antigen: Implication for Design of a Sandwich ELISA.

Avicenna J Med Biotechnol 2019 Jan-Mar;11(1):72-79

Department of Immunology, Faculty of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Background: Prostate cancer is the second most common cancer in men. Prostate-Specific Antigen (PSA) is a tumor-associated glycoprotein with enzymatic activity which is secreted by the prostate gland. Following entry to the blood, 70-90% of PSA forms complexes with protease inhibitors and its enzymatic activity is inhibited. The serum level of PSA is increased and the rate of free PSA (fPSA) to total PSA is decreased in prostate cancer patients. Therefore, measurement of PSA and fPSA in serum is very valuable for diagnosis and prognosis of prostate cancer.

Methods: In the present study, five anti PSA monoclonal Antibodies (mAb) were characterized by Enzyme-Linked Immunosorbent Assay (ELISA) and immunoblotting. For designing a sandwich ELISA, epitope specificity of these antibodies was studied by a competition ELISA. Free PSA was purified by electroelution technique from seminal plasma and used to produce polyclonal anti-fPSA antibody in rabbit. Purified polyclonal antibody (pAb) and mAbs were conjugated with HRP enzyme and Biotin (Bio) to set up the sandwich ELISA.

Results: Three of the mAbs were found to recognize PSA similarly. One of these mAbs (2G3) was paired with anti-fPSA pAb to detect fPSA in serum. Eventually, serum fPSA concentration of 356 subjects was measured and compared by our designed ELISA and a commercial ELISA kit. Our results demonstrated a significant correlation (r=0.68; p<0.001) between the two assays. Sensitivity and specificity of our designed ELISA was 72.4 and 82.8%, respectively.

Conclusion: These results imply suitability of our designed ELISA for detection of fPSA in patients with prostate cancer.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6359702PMC
February 2019

CbpM and CbpG of Streptococcus Pneumoniae Elicit a High Protection in Mice Challenged with a Serotype 19F Pneumococcus.

Iran J Allergy Asthma Immunol 2018 Dec 3;17(6):574-585. Epub 2018 Dec 3.

Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran AND Biotechnology Research Center, Tehran University of Medical Sciences, Tehran, Iran.

Among many pneumococcal antigens, choline-binding proteins (CPBs) display a high immunogenicity in animal models. This study aims to determine the immunogenicity of CbpM, CbpG and CbpL proteins of Streptococcus pneumoniae in a mice model. The genes were cloned into pET21a expression vector and the recombinant proteins were produced. Mice were immunized with the purified recombinant proteins. Subsequently, the mice were challenged with S. pneumoniae ATCC 49619 (2×106 CFU) and their survival and bacterial clearances were followed 24 hours after infection. The antibody responses of the mice were determined by ELISA assay. The opsonophagocytosis assay was performed using rabbit's sera. Passive immunization was carried out using two doses of anti-CbPs antibodies. Finally, these mice were  experimentally infected with virulent bacteria and the protective effects of two doses of 10 and 100 µg/mL by monitoring the survival rate and bacterial clearance were determined at 2, 3 and 7 days after bacterial challenge. The mice actively immunized with CbpM, CbpG and CbpL recombinant proteins showed survival rate of 100%, 85% and 75%, respectively. The survival rates among passively immunized mice groups which received 100 µg/mL dose of anti-CbpM, anti-CbpG and anti- CbpL were 50%, 50% and 25%, respectively. The rates of opsonization with rabbit's antibodies against CbpM, CbpG, and CbpL  at 100 µg/mL doses was 45.6%, 14.7% and 82.3%, and at 10 µg/mL was 12.9%, 12.2% and 9.35%, respectively. Our findings suggest that the recombinant proteins particularly CbpM and CbpG can protect the mice against pneumococcus19F serotype and effectively induce a protective antibody response. Thus, CbpG and CbpM proteins might be used as suitable vaccine candidate in pneumococcal vaccine formulations.
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December 2018

Quantum Dot-labeled Tags Improve Minimal Detection Limit of CA125 in Ovarian Cancer Cells and Tissues.

Iran J Allergy Asthma Immunol 2018 Aug 12;17(4):326-335. Epub 2018 Aug 12.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran AND Reproductive Immunology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran AND Immunology Research Center (IRC), Iran University of Medical Sciences, Tehran, Iran.

In recent years, a lot of attention has been paid to quantum dot (QD) nanoparticles as fluorescent sensors for sensitive and accurate detection of cancer biomarkers. Here, using a homemade specific monoclonal antibody against CA125 and QD525- or FITC-labeled probes, expression of this marker in an ovarian cancer cell line and cancer tissues were traced and optical properties of fluorophores were compared qualitatively and quantitatively. Our results clearly showed that besides lower background and exceptionally higher photobleaching resistance, QD525 exhibited higher fluorescent intensity for both ovarian cancer cell and tissues at different exposure times (p<0.0001) and excitation filter sets (p<0.0001) exemplified by significantly higher staining index (p<0.016). More importantly, the FITC-labeled probe detected antigen-antibody complex at minimum concentration of 0.3 mg/mL of anti-CA125, while reactivity limit decreased to 0.078 mg/mL of anti-CA125 when QD525-labeled probe was applied showing four times higher reactivity level of QD525 probe compared to the same probe labeled with FITC. Based on our results, it seems that QDs are inimitable tags for sensitive detection and localization of ovarian cancer micrometastasis and molecular demarcation of cancer tissues in surgical practice, which subsequently figure out accurate therapeutic approaches.
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http://dx.doi.org/10.18502/ijaai.v17i4.92DOI Listing
August 2018

Differential Effects of Inhibitory and Stimulatory Anti-HER2 Monoclonal Antibodies on AKT/ERK Signaling Pathways

Asian Pac J Cancer Prev 2018 Aug 24;19(8):2255-2262. Epub 2018 Aug 24.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Email: and

Objective: Homo- and heterodimerization of the receptor tyrosine kinase HER2 hyperactivate several downstream signaling pathways, leading to uncontrolled growth and proliferation of tumor cells. Anti-HER2 monoclonal antibodies (mAbs) may induce different effects on HER2 dimerization and signaling. Methods: The effect of two inhibitory (2A8, 1T0) and one stimulatory (1H9) anti-HER2 mAbs either alone or in combination with trastuzumab was investigated on AKT and ERK signaling pathways and HER2 degradation in a human breast cancer cell line (BT-474) by Western blotting. Result: While 1H9 mAb had no significant effect on AKT and ERK signaling pathways, 1T0 and 2A8 mAbs inhibited phosphorylation of both pathways. Combination of 1T0 mAb with trastuzumab resulted in significant synergistic inhibition of both pathways and HER2 degradation, much more potently than the combination of trastuzumab and pertuzumab. Conclusion: Our data indicate that anti-HER2 mAbs may induce different signaling pathways depending on their effect on tumor cell growth and proliferation. The significant inhibition of ERK and AKT phosphorylation by 1T0 alone or particularly in combination with trastuzumab suggests its potential therapeutic application for targeted immunotherapy of HER2 overexpressing malignancies.
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http://dx.doi.org/10.22034/APJCP.2018.19.8.2255DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6171393PMC
August 2018

Therapeutic Monoclonal Antibodies and Emergence of Their Biosimilars.

Avicenna J Med Biotechnol 2018 Apr-Jun;10(2):61

Department of Hybridoma, Monoclonal Antibody Research Center, Avicenna Research Institute, ACECR, Tehran, Iran.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5960060PMC
June 2018

Design and Synthesis of a Biocompatible 1D Coordination Polymer as Anti-Breast Cancer Drug Carrier, 5-Fu: In Vitro and in Vivo Studies.

ACS Appl Mater Interfaces 2018 May 17;10(21):17594-17604. Epub 2018 May 17.

Institute of Low Temperature and Structure Research , Polish Academy of Sciences , P.O. Box 1410, Wroclaw 50-950 , Poland.

Designable coordination polymers with suitable chemical diversities and biocompatible structures have been proposed as a promising class of vehicles for drug delivery systems. Here, we hydrothermally synthesized a novel one-dimensional (1D) coordination polymer, [Zn(HO)K(HBTC)(HO)](HBTC)·2HO, where HBTC = benzene-1,3,5-tricarboxylic acid (trimesic acid), cp.1. As the hydrogen bonds stabilized 1D chains in three dimensions, the cp.1 could be a good candidate for delivering small-molecule chemotherapeutics such as 5-fluorouracil (5-Fu). The synthesized cp.1 showed a remarkable 5-Fu loading of 66% with encapsulation efficiency of 98% and almost complete release process. The 5-Fu-loaded cp.1 displayed a time-dependent cytotoxicity effect against breast cancer cell lines MCF-7 and 4T1. The cellular uptake of cp.1 particles was investigated via confocal laser scanning microscopy using fluorescein isothiocyanate and LysoTracker Red staining. Furthermore, the in vivo antitumor impact of 5-Fu-loaded cp.1 was studied on 4T1 breast cancer BALB/c mice model. The intratumor treatment of 5-Fu-loaded cp.1 demonstrated beneficial antitumor efficacy by postponing tumor growth. These results suggest that the 5-Fu-loaded cp.1 microparticles with a great locoregional delivery can be efficient anticancer drug carriers for further clinical treatments.
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http://dx.doi.org/10.1021/acsami.8b03111DOI Listing
May 2018

Investigation of the Cellular Immune Response to Recombinant Fragments of Filamentous Hemagglutinin and Pertactin of Bordetella pertussis in BALB/c Mice.

J Interferon Cytokine Res 2018 04;38(4):161-170

1 Department of Immunology, Tehran University of Medical Sciences , Tehran, Iran .

Vaccination with whole-cell or acellular (Ac) vaccines has been very effective for the control of pertussis. The immune response to Ac vaccines has been generally associated with a shift toward the Th2 profile. In the present study, overlapping recombinant fragments of filamentous hemagglutinin (FHA) and pertactin (PRN) were produced in Escherichia coli. BALB/c mice were immunized with recombinant FHA and PRN together with the native pertussis toxin and alum or CpG as adjuvant. Immunized mice were subsequently aerosol challenged with Bordetella pertussis. Bacterial growth was assessed in bronchoalveolar lavage samples and the levels of cytokines were quantitated in supernatants of stimulated splenocytes by enzyme-linked immunosorbent assay. Our results demonstrated that both PRN and FHA antigens were able to induce IFN-γ, IL-4, and to some extent IL-17 cytokines in challenged mice. The level of IFN-γ was higher in response to CpG formulated antigens. These findings indicate immunoprotective efficacy of our recombinant FHA and PRN antigens in mice.
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http://dx.doi.org/10.1089/jir.2017.0060DOI Listing
April 2018

All-trans retinoic acid in combination with sodium butyrate enhances specific monoclonal antibody productivity in recombinant CHO cell line.

Bioprocess Biosyst Eng 2018 Jul 4;41(7):961-971. Epub 2018 Apr 4.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

The effects of all-trans retinoic acid (RA) and sodium butyrate (NaBu) on growth, viability and antibody production of two types of transfected Chinese hamster ovary cell lines (CHO-K1 and CHO-S) were investigated using a batch mode cell culture. By adding 0.5 mM NaBu in the CHO-K1 cell culture, the cell specific productivity (Q) and antibody concentration increased by five- and threefold, respectively. The optimal concentration of RA was 100 nM which resulted in twofold increase in antibody production. In a combination model, RA applied at early growth phase of CHO-K1 cells followed by addition of NaBu with lowering culture temperature at the end of stationary phase resulted in two- and threefold increase in Q and final antibody concentration, respectively. The latter strategy was also applied on suspended CHO-S cells with enhanced Q and antibody concentration, but to a lesser extent than the CHO-K1 cells. In conclusion, our results demonstrate that the addition of RA and NaBu along with lowering the culture temperature can increase cell culture period as well as Q and the final concentration of recombinant monoclonal antibody in both CHO-K1 and CHO-S cells without any significant change in binding affinity of the mAb.
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http://dx.doi.org/10.1007/s00449-018-1927-yDOI Listing
July 2018

Diminished Frequency of Menstrual and Peripheral Blood NKT-Like Cells in Patients With Unexplained Recurrent Spontaneous Abortion and Infertile Women.

Reprod Sci 2019 01 25;26(1):97-108. Epub 2018 Mar 25.

1 Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Systemic monitoring of immune system may not precisely outline the local immune status in the uterus. This survey is a continuation of our previous studies on potential usefulness of menstrual blood (MB) immunophenotyping as a tool for investigation of immunological disturbances in pregnancy-related disorders. Peripheral blood (PB) and MB from healthy fertile (n = 15), unexplained recurrent spontaneous abortion (URSA; n = 15), and unexplained infertile women (n = 8) were collected simultaneously in the second day of their menstrual cycle and frequency of natural killer T (NKT)-like cell subpopulations were assessed by flow cytometry. Menstrual blood of all experimental groups contained higher percentage of TCRαβ, CD45RO, and CD16 NKT-like cells compared to corresponding PB. Frequency of MB NKT-like cells in unexplained infertile participants was lower than fertile and URSA groups. Compared to normal participants, patients with URSA had lower frequency of PB TCRαβ and higher CD16, while in infertile woman frequencies of PB CD45RO, CD45RO, CD16, IL17, and MB CD45RO NKT-like cells were lower. Although, PB and MB seemingly have the same histological nature, our results showed that MB contained different composition of NKT-like subsets with different cytokine profiles and could be viewed as one potential biological sample for evaluation of patients with infertility and URSA.
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http://dx.doi.org/10.1177/1933719118766261DOI Listing
January 2019

Immunization with HER2 extracellular subdomain proteins induces cellular response and tumor growth inhibition in mice.

Immunotherapy 2018 03;10(6):511-524

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Aim: We investigated cellular and protective immune responses in mice vaccinated with recombinant HER2 extracellular subdomains.

Materials & Methods: Balb/C mice were immunized with recombinant full HER2 extracellular domain and subdomain proteins. Humoral and cellular immune response and antitumor effect was evaluated using a syngeneic mice tumor model.

Results: All recombinant proteins induced secretion of IL-4 and particularly IFN-γ and IL-17 cytokines. Challenging of immunized mice with stable 4T1-HER2 transfected cells resulted in partial but significant tumor growth inhibition in all groups of mice particularly those immunized with fHER2-ECD together with CPG.

Conclusion: Our results suggest that the recombinant HER2-ECD subdomains induce mainly Th1 and Th17 responses, which seem to contribute to tumor growth inhibition in syngeneic mice.
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http://dx.doi.org/10.2217/imt-2017-0181DOI Listing
March 2018

Rearing and Biology of , the Main Vector of Anthroponotic Cutaneous Leishmaniasis in Iran.

J Arthropod Borne Dis 2017 Dec 30;11(4):504-514. Epub 2017 Dec 30.

Department of Medical Entomology and Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Background: Establishment of sand flies laboratory colonies is essential to understand various biological aspects of Phlebotominae sand flies. The aims of the current study were to establish the colony of Parrot (1917), the main vector of anthroponotic cutaneous leishmaniasis in old world, and to study biological parameters of this species.

Methods: The sand flies were reared at 26-28 °C temperature, 14:10 (light: dark) photoperiod and 70-80% relative humidity. Larval diet was a composted mixture of rabbit faces and rabbit pellets which is prepared through a special process. First to fifth generations of were used to define biological parameters.

Results: Results showed that, blood feeding percentage were 42% on chicken, 21% on BALB/c and 37% on golden hamster. Average time of blood digestion, egg incubation, 1 instar larva, pupa and adult emerging was recorded at 3.4, 8.7, 15, 33.3 and 41.2 days after blood feeding, respectively. Mean number of laid eggs was 55.1 and retained eggs were 35 per a female. Fecundity and production rate were 61.6%, and 42.2% respectively. Average longevity recorded at 15.2 days for females and 14.8 days for males.

Conclusion: Colony of . has been established for the first time in Iran. Average interval time from egg to adult of this species was 32.5 days. Chicken and golden hamster were recommended as a blood source for colony initiation and routine blood feeding, respectively.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5775157PMC
December 2017

Generation and Characterization of Siglec-F-Specific Monoclonal Antibodies.

Iran J Allergy Asthma Immunol 2017 Dec;16(6):460-470

Reproductive Immunology Research Center, Avicenna Research Institute, Academic Center for Education, Culture and Research (ACECR), Tehran, Iran AND Immunology Research Center, Iran University of Medical Sciences, Tehran, Iran.

Siglec-F (SF) is a surface glycoprotein expressed by mouse eosinophils and induces caspase- and mitochondria-dependent apoptosis after engagement with its cognate ligand or specific antibodies. This targeting eosinophils by monoclonal antibodies may help diverse diseases associated with increased frequency of eosinophils including allergy and asthma. In this paper, production of murine and rat monoclonal antibodies (mAbs) against Siglec-F has been addressed. Balb/c mice were immunized with siglec-F1 (SF1) and siglec-F2 (SF2) synthetic peptides conjugated to a carrier protein. Rats were immunized with Chinese hamster ovary CHO cells overexpressing Siglec-F (CHO-SF) or with Siglec-F-human immunoglobulin FC fusion protein (CHO-SF-Ig). Hybridomas were produced by standard protocol and screened for their reactivity by enzyme-linked immunosorbent assay (ELISA), western blotting (WB), and flow cytometry. In parallel, polyclonal antibodies were generated in New Zealand White rabbits immunized with SF1 and SF2 peptides. Three mouse and three rat mAbs were generated against synthetic peptides and SF-Ig, respectively. All mouse monoclonal and rabbit polyclonal antibodies reacted well with immunizing molecules in ELISA and detected specific band of Siglec-F in WB. However, they failed to detect native molecule in flow cytometry analysis. Quite the contrary, rat mAbs did not reacted with the denatured protein in WB, instead exhibited significant reactivity with CHO-SF cells in flow cytometry. Based on the heavily glycosylated nature of Siglec-F, it seems that generation of anti-SF antibodies able to detect native protein needs a properly folded molecule for immunization. Monoclonal antibodies reported here are invaluable tools for studying linear and conformation epitopes of SF and tracing mouse eosinophils.
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December 2017

Inhibition of tumor growth by mouse ROR1 specific antibody in a syngeneic mouse tumor model.

Immunol Lett 2018 01 22;193:35-41. Epub 2017 Nov 22.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran; Monoclonal Antibody Research Center, Avicenna Research Institute, ACECR, Tehran, Iran. Electronic address:

Introduction: Immunotherapy with tumor-associated antigens (TAAs) is a potentially powerful approach to eradicate tumor cells. The receptor tyrosine kinase-like orphan receptor 1 (ROR1) plays a crucial role for survival of tumor cells and is overexpressed in various malignancies. In the present study, we developed a syngeneic mouse tumor model to assess anti-tumor effect of mouse ROR1 specific polyclonal antibody (pAb) in vivo.

Materials And Methods: Mouse ROR1 specific antibody was produced in rabbit using recombinant ROR1 protein. Tow mouse tumor cell lines, (4T1 and CT26), were transfected with full length mouse ROR1 construct and stable clones were selected and characterized by immunocytochemistry, Western blot and flow cytometry. In vitro and in vivo anti-tumor activities of anti-ROR1 antibody were assessed by XTT and syngeneic BALB/c mouse model, respectively.

Results: We successfully established two mouse ROR1-overexpressing tumor cell lines. The in vitro results indicate that the ROR1pAb did not significantly inhibit growth of ROR1+ cell lines. One of these cell lines (CT26-ROR1) was implanted in syngeneic BALB/c mice to assess anti-ROR1 tumor inhibitory activity in vivo. The tumor size was significantly reduced in mice treated with ROR1 specific pAb.

Conclusion: Our results demonstrated for the first time tumor inhibitory effect of mouse ROR1 specific antibody in a syngeneic mouse tumor model. This model is a promising tool for preclinical assessment of ROR1 therapeutics and investigation of the underling molecular mechanisms.
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http://dx.doi.org/10.1016/j.imlet.2017.11.010DOI Listing
January 2018

Epitope Mapping of Human HER2 Specific Mouse Monoclonal Antibodies Using Recombinant Extracellular Subdomains

Asian Pac J Cancer Prev 2017 11 26;18(11):3103-3110. Epub 2017 Nov 26.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Email:

Background: Human epidermal growth factor receptor 2 (HER2) is overexpressed in several human malignancies and numerous studies have indicated that it plays important roles in the development and maintenance of the malignant phenotype. Targeting of HER2 molecules with monoclonal antibodies (mAbs) is a promising therapeutic approach. However, anti-HER2 mAbs affect cancer cells differently, depending on the distinct epitopes which are the targets. Methods: Reactivity of a panel of 8 mouse anti-HER2 mAbs was investigated by ELISA and Western blotting using different subdomains of the extracellular domain (ECD) of HER2. All subdomains, including I, II, III, IV, I+II, III+IV and full HER2-ECD were constructed and expressed in CHO cells. Cross-reactivity of the mAbs with other members of the human HER family and Cynomolgus HER2 was also studied by ELISA. The mAbs were also tested by immunohistochemistry (IHC) using HER2 positive breast cancer tissues. Results: Our results demonstrated that 3 out of 8 mAbs detected conformational epitopes (1T0, 2A8 and 1B5), while 5 mAbs identified linear epitopes (1F2, 1H9, 4C7, 1H6 and 2A9). Three of the mAbs recognized subdomain I, one reacted with subdomain I+II, 2 recognized either subdomain III or IV and 2 recognized subdomain III+IV. However, none of our mAbs recognized the subdomain II alone. The mAbs displayed either inhibitory or stimulatory effects on HER2-overexpressing tumor cells and did not react with other members of the human HER family. The pattern of IHC results implied better reactivity of the mAbs recognizing linear epitopes. Conclusions: Our findings suggest that paired subdomains of HER2 are essential for mapping of mAbs recognizing conformational epitopes. Moreover, there seems to be no association between subdomain specificity and antitumor activity of our anti-HER2 mAbs.
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http://dx.doi.org/10.22034/APJCP.2017.18.11.3103DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5773798PMC
November 2017

Hersintuzumab: A novel humanized anti-HER2 monoclonal antibody induces potent tumor growth inhibition.

Invest New Drugs 2018 04 6;36(2):171-186. Epub 2017 Oct 6.

Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Humanized monoclonal antibodies (mAbs) against HER2 including trastuzumab and pertuzumab are widely used to treat HER2 overexpressing metastatic breast cancers. These two mAbs recognize distinct epitopes on HER2 and their combination induces a more potent blockade of HER2 signaling than trastuzumab alone. Recently, we have reported characterization of a new chimeric mAb (c-1T0) which binds to an epitope different from that recognized by trastuzumab and significantly inhibits proliferation of HER2 overexpressing tumor cells. Here, we describe humanization of this mAb by grafting all six complementarity determining regions (CDRs) onto human variable germline genes. Humanized VH and VL sequences were synthesized and ligated to human γ1 and κ constant region genes using splice overlap extension (SOE) PCR. Subsequently, the humanized antibody designated hersintuzumab was expressed and characterized by ELISA, Western blot and flow cytometry. The purified humanized mAb binds to recombinant HER2 and HER2-overexpressing tumor cells with an affinity comparable with the chimeric and parental mouse mAbs. It recognizes an epitope distinct from those recognized by trastuzumab and pertuzumab. Binding of hersintuzumab to HER2 overexpressing tumor cells induces G1 cell cycle arrest, inhibition of ERK and AKT signaling pathways and growth inhibition. Moreover, hersintuzumab could induce antibody-dependent cell cytotoxicity (ADCC) on BT-474 cells. This new humanized mAb is a potentially valuable tool for single or combination breast cancer therapy.
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http://dx.doi.org/10.1007/s10637-017-0518-0DOI Listing
April 2018