8,911 results match your criteria antigenic diversity


Modulation of the tumor micro-environment by CD8 T cell-derived cytokines.

Curr Opin Immunol 2021 Apr 13;69:65-71. Epub 2021 Apr 13.

Division of Molecular Oncology & Immunology, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands. Electronic address:

Upon their activation, CD8 T cells in the tumor micro-environment (TME) secrete cytokines such as IFNγ, TNFα, and IL-2. While over the past years a major interest has developed in the antigenic signals that induce such cytokine release, our understanding of the cells that subsequently sense these CD8 T-cell secreted cytokines is modest. Here, we review the current insights into the spreading behavior of CD8 T-cell-secreted cytokines in the TME. Read More

View Article and Full-Text PDF

Canine parvovirus type 2c in Vietnam continues to produce distinct descendants with new mutations restricted to Vietnamese variants.

Arch Virol 2021 Apr 16. Epub 2021 Apr 16.

Immunology Department, Institute of Biotechnology (IBT), Vietnam Academy of Science and Technology (VAST), 18. Hoang Quoc Viet Rd., Cau Giay, Hanoi, Vietnam.

Viral protein 2 (VP2) of canine parvovirus (CPV) exhibits a high degree of genetic and antigenic diversity. We analyzed 88 Vietnamese CPV-VP2 sequences (1755 bp), 34 from this study and 54 from previous studies, and discovered a new sublineage, "new var.", within the lineage CPV-2c-"new", characterized by the mutation 5G/447M, which is restricted to the Vietnamese isolates. Read More

View Article and Full-Text PDF

Vaccination with prefusion-stabilized respiratory syncytial virus fusion protein induces genetically and antigenically diverse antibody responses.

Immunity 2021 Apr 5;54(4):769-780.e6. Epub 2021 Apr 5.

Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA. Electronic address:

An effective vaccine for respiratory syncytial virus (RSV) is an unrealized public health goal. A single dose of the prefusion-stabilized fusion (F) glycoprotein subunit vaccine (DS-Cav1) substantially increases serum-neutralizing activity in healthy adults. We sought to determine whether DS-Cav1 vaccination induces a repertoire mirroring the pre-existing diversity from natural infection or whether antibody lineages targeting specific epitopes predominate. Read More

View Article and Full-Text PDF

Strategies Targeting Hemagglutinin as a Universal Influenza Vaccine.

Vaccines (Basel) 2021 Mar 13;9(3). Epub 2021 Mar 13.

Nebraska Center for Virology, School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE 68504, USA.

Influenza virus has significant viral diversity, both through antigenic drift and shift, which makes development of a vaccine challenging. Current influenza vaccines are updated yearly to include strains predicted to circulate in the upcoming influenza season, however this can lead to a mismatch which reduces vaccine efficacy. Several strategies targeting the most abundant and immunogenic surface protein of influenza, the hemagglutinin (HA) protein, have been explored. Read More

View Article and Full-Text PDF

Worldwide Prevalence of Small Ruminant Lentiviruses in Sheep: A Systematic Review and Meta-Analysis.

Animals (Basel) 2021 Mar 11;11(3). Epub 2021 Mar 11.

Department of Animal Pathology, University of Zaragoza, 50013 Zaragoza, Spain.

Small Ruminant Lentiviruses (SRLV) are highly prevalent retroviruses with significant genetic diversity and antigenic heterogeneity that cause a progressive wasting disease of sheep called Maedi-visna. This work provides a systematic review and meta-analysis of the last 40 years (1981-2020) of scientific publications on SRLV individual and flock prevalence. Fifty-eight publications and 314 studies were included. Read More

View Article and Full-Text PDF

Blood Analyte Changes of Wild-Caught Adult Almaco Jack in Response to Acclimation to Recirculating Aquaculture Systems and Hyposalinity Treatment.

J Aquat Anim Health 2021 Mar 30. Epub 2021 Mar 30.

Tropical Aquaculture Laboratory, Program in Fisheries and Aquatic Sciences, School of Forest Resources and Conservation, Institute of Food and Agricultural Sciences, University of Florida, Ruskin, Florida, 33570, USA.

Despite the utility of blood analyte evaluation as a diagnostic tool to assist in monitoring the health of marine fishes, baseline data are often lacking for many commercially important finfish species. The objective of this study was to compare hematology and plasma chemistry data for adult wild-caught Almaco Jack Seriola rivoliana at time of capture and again following a period of acclimation to a recirculating aquaculture system and hyposalinity treatment. A total of 30 clinically healthy adult fish were caught via hook and line in the eastern Gulf of Mexico, approximately 120 mi offshore from Madeira Beach, Florida. Read More

View Article and Full-Text PDF

Functional insights from a surface antigen mRNA-bound proteome.

Elife 2021 Mar 30;10. Epub 2021 Mar 30.

Centre for Molecular Biology of Heidelberg University (ZMBH), Heidelberg, Germany.

is the causative agent of human sleeping sickness. The parasites' variant surface glycoprotein (VSG) enables them to evade adaptive immunity via antigenic variation. VSG comprises 10% of total cell protein and the high stability of VSG mRNA is essential for trypanosome survival. Read More

View Article and Full-Text PDF

In silico comparative study of SARS-CoV-2 proteins and antigenic proteins in BCG, OPV, MMR and other vaccines: evidence of a possible putative protective effect.

BMC Bioinformatics 2021 Mar 26;22(1):163. Epub 2021 Mar 26.

Laboratory of Clinical Virology, WHO Regional Reference Laboratory for Poliomyelitis and Measles for the EMR, Institut Pasteur de Tunis, University of Tunis El Manar, 13 place Pasteur, BP74 1002 le Belvédère, Tunis, Tunisia.

Background: Coronavirus Disease 2019 (COVID-19) is a viral pandemic disease that may induce severe pneumonia in humans. In this paper, we investigated the putative implication of 12 vaccines, including BCG, OPV and MMR in the protection against COVID-19. Sequences of the main antigenic proteins in the investigated vaccines and SARS-CoV-2 proteins were compared to identify similar patterns. Read More

View Article and Full-Text PDF

Repeat-Driven Generation of Antigenic Diversity in a Major Human Pathogen, .

Front Cell Infect Microbiol 2021 3;11:614665. Epub 2021 Mar 3.

Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden.

, a zoonotic kinetoplastid protozoan parasite, is the causative agent of American trypanosomiasis (Chagas disease). Having a very plastic, repetitive and complex genome, the parasite displays a highly diverse repertoire of surface molecules, with pivotal roles in cell invasion, immune evasion and pathogenesis. Before 2016, the complexity of the genomic regions containing these genes impaired the assembly of a genome at chromosomal level, making it impossible to study the structure and function of the several thousand repetitive genes encoding the surface molecules of the parasite. Read More

View Article and Full-Text PDF

Adenovirus-vectored T cell vaccine for hepacivirus shows reduced effectiveness against a CD8 T cell escape variant in rats.

PLoS Pathog 2021 Mar 18;17(3):e1009391. Epub 2021 Mar 18.

Center for Vaccines and Immunity, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, Ohio, United States of America.

There is an urgent need for a vaccine to prevent chronic infection by hepatitis C virus (HCV) and its many genetic variants. The first human vaccine trial, using recombinant viral vectors that stimulate pan-genotypic T cell responses against HCV non-structural proteins, failed to demonstrate efficacy despite significant preclinical promise. Understanding the factors that govern HCV T cell vaccine success is necessary for design of improved immunization strategies. Read More

View Article and Full-Text PDF

Persistent T Cell Repertoire Perturbation and T Cell Activation in HIV After Long Term Treatment.

Front Immunol 2021 25;12:634489. Epub 2021 Feb 25.

Division of Infection and Immunity, University College London, London, United Kingdom.

Objective: In people living with HIV (PLHIV), we sought to test the hypothesis that long term anti-retroviral therapy restores the normal T cell repertoire, and investigate the functional relationship of residual repertoire abnormalities to persistent immune system dysregulation.

Methods: We conducted a case-control study in PLHIV and HIV-negative volunteers, of circulating T cell receptor repertoires and whole blood transcriptomes by RNA sequencing, complemented by metadata from routinely collected health care records.

Results: T cell receptor sequencing revealed persistent abnormalities in the clonal T cell repertoire of PLHIV, characterized by reduced repertoire diversity and oligoclonal T cell expansion correlated with elevated CD8 T cell counts. Read More

View Article and Full-Text PDF
February 2021

Machine Learning Prediction and Experimental Validation of Antigenic Drift in H3 Influenza A Viruses in Swine.

mSphere 2021 03 17;6(2). Epub 2021 Mar 17.

Virus and Prion Research Unit, National Animal Disease Center, USDA-ARS, Ames, Iowa, USA

The antigenic diversity of influenza A viruses (IAV) circulating in swine challenges the development of effective vaccines, increasing zoonotic threat and pandemic potential. High-throughput sequencing technologies can quantify IAV genetic diversity, but there are no accurate approaches to adequately describe antigenic phenotypes. This study evaluated an ensemble of nonlinear regression models to estimate virus phenotype from genotype. Read More

View Article and Full-Text PDF

A broadly neutralizing monoclonal antibody induces broad protection against heterogeneous PRRSV strains in piglets.

Vet Res 2021 Mar 16;52(1):45. Epub 2021 Mar 16.

Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Xianyang, Shaanxi, China.

Neutralizing antibodies (NAbs) have attracted attention as tools for achieving PRRSV control and prevention, but viral antigenic variation undermines the abilities of NAbs elicited by attenuated PRRSV vaccines to confer full protection against heterogeneous PRRSV field isolates. As demonstrated in this study, the monoclonal antibody (mAb) mAb-PN9cx3 exhibited broad-spectrum recognition and neutralizing activities against PRRSV-1 and PRRSV-2 strains in vitro. Furthermore, in vivo experiments revealed that the administration of two 10-mg doses of mAb-PN9cx3 before and after the inoculation of piglets with heterologous PRRSV isolates (HP-PRRSV-JXA1 or PRRSV NADC30-like strain HNhx) resulted in significant reduction of the PRRSV-induced pulmonary pathological changes and virus loads in porcine alveolar macrophages (PAMs) compared with the results obtained with mAb-treated isotype controls. Read More

View Article and Full-Text PDF

A Comprehensive Review of Viral Characteristics, Transmission, Pathophysiology, Immune Response, and Management of SARS-CoV-2 and COVID-19 as a Basis for Controlling the Pandemic.

Front Immunol 2021 26;12:631139. Epub 2021 Feb 26.

Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, Doha, Qatar.

COVID-19 emerged from China in December 2019 and during 2020 spread to every continent including Antarctica. The coronavirus, SARS-CoV-2, has been identified as the causative pathogen, and its spread has stretched the capacities of healthcare systems and negatively affected the global economy. This review provides an update on the virus, including the genome, the risks associated with the emergence of variants, mode of transmission, immune response, COVID-19 in children and the elderly, and advances made to contain, prevent and manage the disease. Read More

View Article and Full-Text PDF

The design of multiepitope vaccines from plasmids of diarrheagenic Escherichia coli against diarrhoea infection: Immunoinformatics approach.

Infect Genet Evol 2021 Mar 5;91:104803. Epub 2021 Mar 5.

Discipline of Chemical Engineering, University of KwaZulu-Natal, Howard Campus, Durban 4041, South Africa.

Diarrhoea infection is a major global health public problem and is caused by many organisms including diarrheagenic Escherichia coli pathotypes. The common problem with diarrhoea is the drug resistance of pathogenic bacteria, the most promising alternative means of preventing drug resistance is vaccination. However, there has not been any significant success in the prevention of diarrhoea caused by E. Read More

View Article and Full-Text PDF

Longitudinal antibody repertoire in "mild" versus "severe" COVID-19 patients reveals immune markers associated with disease severity and resolution.

Sci Adv 2021 03 5;7(10). Epub 2021 Mar 5.

Division of Viral Products, Center for Biologics Evaluation and Research (CBER), FDA, Silver Spring, MD 20871, USA.

Limited knowledge exists on immune markers associated with disease severity or recovery in patients with coronavirus disease 2019 (COVID-19). Here, we elucidated longitudinal evolution of SARS-CoV-2 antibody repertoire in patients with acute COVID-19. Differential kinetics was observed for immunoglobulin M (IgM)/IgG/IgA epitope diversity, antibody binding, and affinity maturation in "severe" versus "mild" COVID-19 patients. Read More

View Article and Full-Text PDF

Assessing Parasite Diversity through Comparative Genomics: Implications for Disease Epidemiology and Diagnostics.

Pathogens 2021 Feb 16;10(2). Epub 2021 Feb 16.

Department of Tropical Medicine, School of Public Health and Tropical Medicine, Vector Borne Infectious Disease Research Center, Tulane University, New Orleans, LA 70112, USA.

Chagas disease is an important vector-borne neglected tropical disease that causes great health and economic losses. The etiological agent, , is a protozoan parasite endemic to the Americas, comprised by important diversity, which has been suggested to contribute to poor serological diagnostic performance. Current nomenclature describes seven discrete typing units (DTUs), or lineages. Read More

View Article and Full-Text PDF
February 2021

Advances in the development of Salmonella-based vaccine strategies for protection against Salmonellosis in humans.

J Appl Microbiol 2021 Mar 4. Epub 2021 Mar 4.

Center for Vaccine Development and Global Health, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA.

Salmonella spp. are important human pathogens globally causing millions of cases of typhoid fever and non-typhoidal salmonellosis annually. There are only a few vaccines licensed for use in humans which all target Salmonella enterica serovar Typhi. Read More

View Article and Full-Text PDF

Sirtuin GdSir2.4 participates in the regulation of rRNA transcription in the Giardia duodenalis parasite.

Mol Microbiol 2021 Mar 4. Epub 2021 Mar 4.

Department of Genetics and Molecular Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Mexico City, Mexico.

Giardia duodenalis is a parasite of great medical interest due to the number of infections it causes worldwide each year. Although research on epigenetic mechanisms in this protist has only begun recently, epigenetic regulation has already been shown to have important roles in encystation, antigenic variation, and resistance to antibiotics in Giardia. In this work, we show that a Giardia ortholog of Sir2, GdSir2. Read More

View Article and Full-Text PDF

Cross-reactivity of antibody responses to Borrelia afzelii OspC: Asymmetry and host heterogeneity.

Infect Genet Evol 2021 Feb 27;91:104793. Epub 2021 Feb 27.

Department of Biology, Lund University, Sölvegatan 35, 223 62 Lund, Sweden. Electronic address:

The tick-transmitted bacterium Borrelia afzelii consists of a number of antigenically different strains - often defined by outer surface protein C (OspC) genotype - that coexist at stable frequencies in host populations. To investigate how host antibody responses affect strain coexistence, we measured antibody cross-reactivity to three different OspC types (OspC 2, 3 and 9) in three different strains of laboratory mice (BALB/c, C3H and C57BL/6). The extent of cross-reactivity differed between mouse strains, being higher in C3H than BALB/c and C57BL/6. Read More

View Article and Full-Text PDF
February 2021

Worldwide genetic variations in high-risk human papillomaviruses capsid L1 gene and their impact on vaccine efficiency.

Gene 2021 May 23;782:145533. Epub 2021 Feb 23.

Medical Biotechnology Center, Moroccan Foundation for Advanced Science, Innovation and Research, MAScIR, Rabat, Morocco. Electronic address:

Background: Human papillomavirus is the most common sexually transmitted infection. It is associated with different cancers, mainly cervical cancer, which remains the fourth most frequent cancer among women worldwide; it is also related to anogenital (anus, vulvar, vagina, and penis) and oropharyngeal cancers. Vaccination against HPV infection is the major way of prevention, and it has demonstrated impressive efficacy in reducing cervical cancer incidence. Read More

View Article and Full-Text PDF

Transmission of SARS-CoV-2 in domestic cats imposes a narrow bottleneck.

PLoS Pathog 2021 02 26;17(2):e1009373. Epub 2021 Feb 26.

Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States of America.

The evolutionary mechanisms by which SARS-CoV-2 viruses adapt to mammalian hosts and, potentially, undergo antigenic evolution depend on the ways genetic variation is generated and selected within and between individual hosts. Using domestic cats as a model, we show that SARS-CoV-2 consensus sequences remain largely unchanged over time within hosts, while dynamic sub-consensus diversity reveals processes of genetic drift and weak purifying selection. We further identify a notable variant at amino acid position 655 in Spike (H655Y), which was previously shown to confer escape from human monoclonal antibodies. Read More

View Article and Full-Text PDF
February 2021

Regional variations and relationships among cytokine profiles, white blood cell counts, and blood mercury concentrations in Steller sea lion (Eumetopias jubatus) pups.

Sci Total Environ 2021 Jun 4;775:144894. Epub 2021 Feb 4.

Department of Veterinary Medicine, University of Alaska Fairbanks, Fairbanks, AK, USA; Veterinary Integrative Biosciences, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX, USA. Electronic address:

The Steller sea lion (SSL) population west of 144°W longitude experienced a significant population decline. While there appears to be a stable or increasing population trend in rookeries in the Gulf of Alaska (GOA) and Southeast Alaska (SEA), some rookeries within the Aleutian Islands (AI) have failed to recover. Previous studies found regional differences in whole blood total mercury concentrations ([THg]) showing more than 20% of AI pups had [THg] above critical thresholds for increased risk of immunological effects and other adverse outcomes. Read More

View Article and Full-Text PDF

Prime-Pull Immunization with a Bivalent M-Protein and Spy-CEP Peptide Vaccine Adjuvanted with CAF®01 Liposomes Induces Both Mucosal and Peripheral Protection from Mutant Streptococcus pyogenes.

mBio 2021 02 23;12(1). Epub 2021 Feb 23.

Institute for Glycomics, Griffith University, Gold Coast, Australia

Infections with and their sequelae are responsible for an estimated 18 million cases of serious disease with >700 million new primary cases and 500,000 deaths per year. Despite the burden of disease, there is currently no vaccine available for this organism. Here, we define a combination vaccine P*17/K4S2 comprising of 20-mer B-cell peptide epitopes, p*17 (a mutant derived from the highly conserved C3-repeat region of the M-protein), and K4S2 (derived from the streptococcal anti-neutrophil factor, Spy-CEP). Read More

View Article and Full-Text PDF
February 2021

Limited diversity in the CD8+ antigen-coding loci in Theileria parva parasites from cattle from southern and eastern Africa.

Vet Parasitol 2021 Mar 5;291:109371. Epub 2021 Feb 5.

Vectors and Vector-borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, South Africa.

Theileria parva infections in cattle causes huge economic losses in the affected African countries, directly impacting the livelihood of the poor small-holder farmers. The current immunization protocol using live sporozoites in eastern Africa, is among the control measures designed to limit T. parva infections in cattle. Read More

View Article and Full-Text PDF

Common allotypes of ER aminopeptidase 1 have substrate-dependent and highly variable enzymatic properties.

J Biol Chem 2021 Feb 19:100443. Epub 2021 Feb 19.

National Centre for Scientific Research "Demokritos", Athens 15341, Greece; Laboratory of Biochemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou 157 84, Greece. Electronic address:

Polymorphic variation of immune system proteins can drive variability of individual immune responses. ER aminopeptidase 1 (ERAP1) generates antigenic peptides for presentation by MHC class I molecules. Coding single nucleotide polymorphisms (SNPs) in ERAP1 have been associated with predisposition to inflammatory rheumatic disease and shown to affect functional properties of the enzyme, but the interplay between combinations of these SNPs as they exist in allotypes, has not been thoroughly explored. Read More

View Article and Full-Text PDF
February 2021

Variation in the HA antigenicity of A(H1N1)pdm09-related swine influenza viruses.

J Gen Virol 2021 Mar 22;102(3). Epub 2021 Feb 22.

United Graduate School of Veterinary Science, Yamaguchi University, Japan.

Since the influenza pandemic in 2009, the causative agent 'A(H1N1)pdm09 virus', has been circulating in both human and swine populations. Although phylogenetic analyses of the haemagglutinin (HA) gene segment have revealed broader genetic diversity of A(H1N1)pdm09-related swine influenza A viruses (swIAVs) compared with human A(H1N1)pdm09 viruses, it remains unclear whether the genetic diversity reflects the antigenic differences in HA. To assess the impact of the diversity of the HA gene of A(H1N1)pdm09-related swIAVs on HA antigenicity, we characterized 12 swIAVs isolated in Japan from 2013 to 2018. Read More

View Article and Full-Text PDF

Epitope variances demonstrated by Blastocystis sp. ST3 symptomatic and asymptomatic isolates.

Trop Biomed 2020 Mar;37(1):210-217

Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.

Blastocystis sp. is an enteric protozoan parasite of humans and many animals. Blastocystis sp. Read More

View Article and Full-Text PDF

An antigenic diversification threshold for falciparum malaria transmission at high endemicity.

PLoS Comput Biol 2021 Feb 19;17(2):e1008729. Epub 2021 Feb 19.

Department of Ecology and Evolution, University of Chicago, Chicago, Illinois, United States of America.

In malaria and several other important infectious diseases, high prevalence occurs concomitantly with incomplete immunity. This apparent paradox poses major challenges to malaria elimination in highly endemic regions, where asymptomatic Plasmodium falciparum infections are present across all age classes creating a large reservoir that maintains transmission. This reservoir is in turn enabled by extreme antigenic diversity of the parasite and turnover of new variants. Read More

View Article and Full-Text PDF
February 2021

A combination of cross-neutralizing antibodies synergizes to prevent SARS-CoV-2 and SARS-CoV pseudovirus infection.

bioRxiv 2021 Feb 12. Epub 2021 Feb 12.

Coronaviruses have caused several epidemics and pandemics including the ongoing coronavirus disease 2019 (COVID-19). Some prophylactic vaccines and therapeutic antibodies have already showed striking effectiveness against COVID-19. Nevertheless, concerns remain about antigenic drift in SARS-CoV-2 as well as threats from other sarbecoviruses. Read More

View Article and Full-Text PDF
February 2021