Publications by authors named "Martina Carducci"

10 Publications

  • Page 1 of 1

Rational Design of a Glycoconjugate Vaccine against Group A .

Int J Mol Sci 2020 Nov 13;21(22). Epub 2020 Nov 13.

GSK Vaccines Institute for Global Health (GVGH), Via Fiorentina 1, 53100 Siena, Italy.

No commercial vaccine is yet available against Group A (GAS), major cause of pharyngitis and impetigo, with a high frequency of serious sequelae in low- and middle-income countries. Group A Carbohydrate (GAC), conjugated to an appropriate carrier protein, has been proposed as an attractive vaccine candidate. Here, we explored the possibility to use GAS Streptolysin O (SLO), SpyCEP and SpyAD protein antigens with dual role of antigen and carrier, to enhance the efficacy of the final vaccine and reduce its complexity. All protein antigens resulted good carrier for GAC, inducing similar anti-GAC IgG response to the more traditional CRM conjugate in mice. However, conjugation to the polysaccharide had a negative impact on the anti-protein responses, especially in terms of functionality as evaluated by an IL-8 cleavage assay for SpyCEP and a hemolysis assay for SLO. After selecting CRM as carrier, optimal conditions for its conjugation to GAC were identified through a Design of Experiment approach, improving process robustness and yield This work supports the development of a vaccine against GAS and shows how novel statistical tools and recent advancements in the field of conjugation can lead to improved design of glycoconjugate vaccines.
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http://dx.doi.org/10.3390/ijms21228558DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7696035PMC
November 2020

GMMA Is a Versatile Platform to Design Effective Multivalent Combination Vaccines.

Vaccines (Basel) 2020 Sep 17;8(3). Epub 2020 Sep 17.

GSK Vaccines Institute for Global Health (GVGH) S.r.l., 53100 Siena, Italy.

Technology platforms are an important strategy to facilitate the design, development and implementation of vaccines to combat high-burden diseases that are still a threat for human populations, especially in low- and middle-income countries, and to address the increasing number and global distribution of pathogens resistant to antimicrobial drugs. Generalized Modules for Membrane Antigens (GMMA), outer membrane vesicles derived from engineered Gram-negative bacteria, represent an attractive technology to design affordable vaccines. Here, we show that GMMA, decorated with heterologous polysaccharide or protein antigens, leads to a strong and effective antigen-specific humoral immune response in mice. Importantly, GMMA promote enhanced immunogenicity compared to traditional formulations (e.g., recombinant proteins and glycoconjugate vaccines), without negative impact to the anti-GMMA immune response. Our findings support the use of GMMA as a "plug and play" technology for the development of effective combination vaccines targeting different bugs at the same time.
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http://dx.doi.org/10.3390/vaccines8030540DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7564227PMC
September 2020

Short Vi-polysaccharide abrogates T-independent immune response and hyporesponsiveness elicited by long Vi-CRM conjugate vaccine.

Proc Natl Acad Sci U S A 2020 09 8;117(39):24443-24449. Epub 2020 Sep 8.

Technology Platform Unit, GSK Vaccines Institute for Global Health (GVGH), 53100 Siena, Italy.

Polysaccharide-protein conjugates have been developed to overcome the T-independent response, hyporesponsiveness to repeated vaccination, and poor immunogenicity in infants of polysaccharides. To address the impact of polysaccharide length, typhoid conjugates made with short- and long-chain fractions of Vi polysaccharide with average sizes of 9.5, 22.8, 42.7, 82.0, and 165 kDa were compared. Long-chain-conjugated Vi (165 kDa) induced a response in both wild-type and T cell-deficient mice, suggesting that it maintains a T-independent response. In marked contrast, short-chain Vi (9.5 to 42.7 kDa) conjugates induced a response in wild-type mice but not in T cell-deficient mice, suggesting that the response is dependent on T cell help. Mechanistically, this was explained in neonatal mice, in which long-chain, but not short-chain, Vi conjugate induced late apoptosis of Vi-specific B cells in spleen and early depletion of Vi-specific B cells in bone marrow, resulting in hyporesponsiveness and lack of long-term persistence of Vi-specific IgG in serum and IgG antibody-secreting cells in bone marrow. We conclude that while conjugation of long-chain Vi generates T-dependent antigens, the conjugates also retain T-independent properties, leading to detrimental effects on immune responses. The data reported here may explain some inconsistencies observed in clinical trials and help guide the design of effective conjugate vaccines.
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http://dx.doi.org/10.1073/pnas.2005857117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7533886PMC
September 2020

Gold nanoparticles morphology does not affect the multivalent presentation and antibody recognition of Group A Streptococcus synthetic oligorhamnans.

Bioorg Chem 2020 06 3;99:103815. Epub 2020 Apr 3.

Department of Chemistry and CRC Materiali Polimerici (LaMPo), University of Milan, Via C. Golgi 19, 20133 Milan, Italy. Electronic address:

The development of novel delivery systems capable of enhancing the antibody binding affinity and immunoactivity of short length saccharide antigens is at the forefront of modern medicine. In this regard, gold nanoparticles (AuNPs) raised great interest as promising nano-vaccine platform, as they do not interfere with the desired immune response and their surface can be easily functionalized, enabling the antigen multivalent presentation. In addition, the nanoparticles morphology can have a great impact on their biological properties. Gram-positive Group A Streptococcus (GAS) is a bacterium responsible for many infections and represents a priority healthcare concern, but a universal vaccine is still unavailable. Since all the GAS strains have a cell wall characterized by a common polyrhamnose backbone, this can be employed as alternative antigen to develop an anti-GAS vaccine. Herein, we present the synthesis of two oligorhamnoside fragments and their corresponding oligorhamnoside-AuNPs, designed with two different morphologies. By competitive ELISA we assessed that both symmetric and anisotropic oligorhamnan nanoparticles inhibit the binding of specific polyclonal serum much better than the unconjugated oligosaccharides.
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http://dx.doi.org/10.1016/j.bioorg.2020.103815DOI Listing
June 2020

GMMA and Glycoconjugate Approaches Compared in Mice for the Development of a Vaccine against Serotype 6.

Vaccines (Basel) 2020 Apr 3;8(2). Epub 2020 Apr 3.

GSK Vaccines Institute for Global Health (GVGH) S.r.l., via Fiorentina 1, 53100 Siena, Italy.

infections are one of the top causes of diarrhea throughout the world, with being predominant in developing countries. Currently, no vaccines are widely available and increasing levels of multidrug-resistance make a high priority for vaccine development. The serotype-specific O-antigen moiety of lipopolysaccharide has been recognized as a key target for protective immunity, and many O-antigen based candidate vaccines are in development. Recently, the Generalized Modules for Membrane Antigens (GMMA) technology has been proposed as an alternative approach to traditional glycoconjugate vaccines for O-antigen delivery. Here, these two technologies are compared for a vaccine against serotype 6. Genetic strategies for GMMA production, conjugation approaches for linkage of the O-antigen to CRM carrier protein, and a large panel of analytical methods for full vaccine characterization have been put in place. In a head-to-head immunogenicity study in mice, GMMA induced higher anti-O-antigen IgG than glycoconjugate administered without Alhydrogel. When formulated on Alhydrogel, GMMA and glycoconjugate elicited similar levels of persistent anti-O-antigen IgG with bactericidal activity. Glycoconjugates are a well-established bacterial vaccine approach, but can be costly, particularly when multicomponent preparations are required. With similar immunogenicity and a simpler manufacturing process, GMMA are a promising strategy for the development of a vaccine against .
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http://dx.doi.org/10.3390/vaccines8020160DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7349896PMC
April 2020

Development of FAcE (Formulated Alhydrogel competitive ELISA) method for direct quantification of OAg present in Shigella sonnei GMMA-based vaccine and its optimization using Design of Experiments approach.

J Immunol Methods 2019 08 27;471:11-17. Epub 2019 Apr 27.

GSK Vaccines Institute for Global Health (GVGH) S.r.l., Siena, Italy. Electronic address:

Many formulated vaccines, including 1790GAHB Shigella sonnei GMMA-based vaccine, contain Alhydrogel (aluminum hydroxide), consequently the antigen content must be determined in the formulated final vaccine product, as required by regulatory authorities. The direct quantification of antigens adsorbed on aluminum salts is difficult, and antigens may need to be extracted using laborious and often ineffective desorption procedures. To directly quantify the sugar vaccine target in the LPS of 1790GAHB, we have developed a new FAcE (Formulated Alhydrogel competitive ELISA) method. FAcE is an immunoassay based on the competition between S. sonnei LPS, coated on the ELISA plate, and the LPS in formulated S. sonnei GMMA, in binding a specific monoclonal antibody. To optimize the method, which is as easy to perform as a standard ELISA, we have applied a Design of Experiments (DOE) approach. A model was found to define the significant assay variables and to predict their impact on the output responses. Results obtained using the DOE optimized FAcE assay showed that the method is sensitive (0.02 μg/mL lower detection limit), precise, reproducible and can accurately quantify independently formulated drug products, making it a useful tool in routine tests of Alhydrogel-based vaccines. We are currently using this method to determine S. sonnei vaccine potency, stability and lot-to-lot variations, and are broadening its applicability to quantify active ingredients of other Alhydrogel GMMA-vaccines and in multivalent vaccines formulations.
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http://dx.doi.org/10.1016/j.jim.2019.04.012DOI Listing
August 2019

The SH2 domain interaction landscape.

Cell Rep 2013 Apr 28;3(4):1293-305. Epub 2013 Mar 28.

Department of Biology, University of Rome Tor Vergata, I-00133 Rome, Italy.

Members of the SH2 domain family modulate signal transduction by binding to short peptides containing phosphorylated tyrosines. Each domain displays a distinct preference for the sequence context of the phosphorylated residue. We have developed a high-density peptide chip technology that allows for probing of the affinity of most SH2 domains for a large fraction of the entire complement of tyrosine phosphopeptides in the human proteome. Using this technique, we have experimentally identified thousands of putative SH2-peptide interactions for more than 70 different SH2 domains. By integrating this rich data set with orthogonal context-specific information, we have assembled an SH2-mediated probabilistic interaction network, which we make available as a community resource in the PepspotDB database. A predicted dynamic interaction between the SH2 domains of the tyrosine phosphatase SHP2 and the phosphorylated tyrosine in the extracellular signal-regulated kinase activation loop was validated by experiments in living cells.
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http://dx.doi.org/10.1016/j.celrep.2013.03.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4110347PMC
April 2013

The protein interaction network mediated by human SH3 domains.

Biotechnol Adv 2012 Jan-Feb;30(1):4-15. Epub 2011 Jun 29.

Department of Biology, University of Rome Tor Vergata, Via della Ricerca Scientifica, Rome, Italy.

Families of conserved protein domains, specialized in mediating interactions with short linear peptide motifs, are responsible for the formation of a variety of dynamic complexes in the cell. An important subclass of these motifs are characterized by a high proline content and play a pivotal role in biological processes requiring the coordinated assembly of multi-protein complexes. This is achieved via interaction of proteins containing modules such as Src Homology-3 (SH3) or WW domains and specific proline rich patterns. Here we make available via a publicly accessible database a synopsis of our current understanding of the interaction landscape of the human SH3 protein family. This is achieved by integrating an information extraction strategy with a new experimental approach. In a first approach we have used a text mining strategy to capture a large number of manuscripts reporting interactions between SH3 domains and target peptides. Relevant information was annotated in the MINT database. In a second experimental approach we have used a variant of the WISE (Whole Interactome Scanning Experiment) strategy to probe a large number of naturally occurring and chemically-synthesized peptides arrayed at high density on a glass surface. By this method we have tested 60 human SH3 domains for their ability to bind a collection of 9192 poly-proline containing peptides immobilized on a glass chip. To evaluate the quality of the resulting interaction dataset, we retested some of the interactions on a smaller scale and performed a series of pull down experiments on native proteins. Peptide chips, pull down assays, SPOT synthesis and phage display experiments have allowed us to further characterize the specificity and promiscuity of proline-rich binding domains and to map their interaction network. Both the information captured from the literature and the interactions inferred from the peptide chip experiments were collected and stored in the PepspotDB (http://mint.bio.uniroma2.it/PepspotDB/).
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http://dx.doi.org/10.1016/j.biotechadv.2011.06.012DOI Listing
July 2012

Enriching the viral-host interactomes with interactions mediated by SH3 domains.

Amino Acids 2010 May 2;38(5):1541-7. Epub 2009 Nov 2.

Department of Biology, University of Rome Tor Vergata, Via della Ricerca Scientifica, 00133, Rome, Italy.

Protein-protein interactions play an essential role in the regulation of most cellular processes. The process of viral infection is no exception and many viral pathogenic strategies involve targeting and perturbing host-protein interactions. The characterization of the host protein subnetworks disturbed by invading viruses is a major goal of viral research and may contribute to reveal fundamental biological mechanisms and to identify new therapeutic strategies. To assist in this approach, we have developed a database, VirusMINT, which stores in a structured format most of the published interactions between viral and host proteome. Although SH3 are the most ubiquitous and abundant class of protein binding modules, VirusMINT contains only a few interactions mediated by this domain class. To overcome this limitation, we have applied the whole interactome scanning experiment approach to identify interactions between 15 human SH3 domains and viral proline-rich peptides of two oncogenic viruses, human papillomavirus type 16 and human adenovirus A type 12. This approach identifies 114 new potential interactions between the human SH3 domains and proline-rich regions of the two viral proteomes.
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http://dx.doi.org/10.1007/s00726-009-0375-zDOI Listing
May 2010

The central proline rich region of POB1/REPS2 plays a regulatory role in epidermal growth factor receptor endocytosis by binding to 14-3-3 and SH3 domain-containing proteins.

BMC Biochem 2008 Jul 22;9:21. Epub 2008 Jul 22.

Department of Biology, University of Rome Tor Vergata, Via della Ricerca Scientifica, 00133 Rome, Italy.

Background: The human POB1/REPS2 (Partner of RalBP1) protein is highly conserved in mammals where it has been suggested to function as a molecular scaffold recruiting proteins involved in vesicular traffic and linking them to the actin cytoskeleton remodeling machinery. More recently POB1/REPS2 was found highly expressed in androgen-dependent prostate cancer cell lines, while one of its isoforms (isoform 2) is down regulated during prostate cancer progression.

Results: In this report we characterize the central proline rich domain of POB1/REPS2 and we describe for the first time its functional role in receptor endocytosis. We show that the ectopic expression of this domain has a dominant negative effect on the endocytosis of activated epidermal growth factor receptor (EGFR) while leaving transferrin receptor endocytosis unaffected. By a combination of different approaches (phage display, bioinformatics predictions, peptide arrays, mutagenic analysis, in vivo co-immunoprecipitation), we have identified two closely spaced binding motifs for 14-3-3 and for the SH3 of the proteins Amphiphysin II and Grb2. Differently from wild type, proline rich domains that are altered in these motifs do not inhibit EGFR endocytosis, suggesting that these binding motifs play a functional role in this process.

Conclusion: Our findings are relevant to the characterization of the molecular mechanism underlying the involvement of POB1/REPS2, SH3 and 14-3-3 proteins in receptor endocytosis, suggesting that 14-3-3 could work by bridging the EGF receptor and the scaffold protein POB1/REPS2.
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http://dx.doi.org/10.1186/1471-2091-9-21DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2494995PMC
July 2008