HLA alleles associated with the adaptive immune response to smallpox vaccine: a replication study

Immune Response and Molecular Mechanisms of Cardiovascular Adverse Effects of Spike Proteins from SARS-CoV-2 and mRNA Vaccines

The SARS-CoV-2 (severe acute respiratory syndrome coronavirus responsible for the COVID-19 disease) uses the Spike proteins of its envelope for infecting target cells expressing on the membrane the angiotensin converting enzyme 2 (ACE2) enzyme that acts as a receptor. To control the pandemic, genetically engineered vaccines have been designed for inducing neutralizing antibodies against the Spike proteins. These vaccines do not act like traditional protein-based vaccines, as they deliver the message in the form of mRNA or DNA to host cells that then produce and expose the Spike protein on the membrane (from which it can be shed in soluble form) to alert the immune system. Mass vaccination has brought to light various adverse effects associated with these genetically based vaccines, mainly affecting the circulatory and cardiovascular system. ACE2 is present as membrane-bound on several cell types, including the mucosa of the upper respiratory and of the gastrointestinal tracts, the endothelium, the platelets, and in soluble form in the plasma. The ACE2 enzyme converts the vasoconstrictor angiotensin II into peptides with vasodilator properties. Here we review the pathways for immunization and the molecular mechanisms through which the Spike protein, either from SARS-CoV-2 or encoded by the mRNA-based vaccines, interferes with the Renin-Angiotensin-System governed by ACE2, thus altering the homeostasis of the circulation and of the cardiovascular system. Understanding the molecular interactions of the Spike protein with ACE2 and the consequent impact on cardiovascular system homeostasis will direct the diagnosis and therapy of the vaccine-related adverse effects and provide information for development of a personalized vaccination that considers pathophysiological conditions predisposing to such adverse events.

The effective factors in human-specific tropism and viral pathogenicity in orthopoxviruses

The orthopoxvirus (OPV) genus includes several species that infect humans, including variola, monkeypox, vaccinia, and cowpox. Variola and monkeypox are often life-threatening diseases, while vaccinia and cowpox are usually associated with local lesions. The epidemic potential for OPVs may be lower than respiratory-borne viruses or RNA viruses. However, OPVs are notable for their spread and distribution in different environments and among different hosts. The emergence or re-emergence of OPVs in the human population can also occur in wild or domestic animals as intermediate hosts. More effective and safer vaccines for poxvirus can be developed by understanding how immunity is regulated in poxvirus and vaccines for DNA viruses. Downstream events in cells affected by the virus are regulated functionally by a series of characteristics that are affected by host cell interactions and responses of cells against viral infections, including the interferon pathway and apoptosis. Furthermore, infection outcome is greatly influenced by the distinct selection of host-range and immune-modulatory genes that confer the potential for pathogenesis and host-to-host transmission and the distinct host-range properties of each immune-modulatory gene. The present study reviewed the effective factors in human-restricted tropism and virus pathogenicity in OPVs.

Genetic predisposition to adverse events in Chinese children aged 3-24 months after diphtheria, tetanus, acellular pertussis and haemophilus influenzae type b combined vaccination

BACKGROUND

Post-vaccination safety is a major public health concern. The genetic predisposition on immune response has not been clearly identified. Clarifying whether individual genetic predisposition plays a role on adverse events (AEs) is critical for the prevention of AEs.

METHODS

From July 2019 to June 2020, we performed a case-control study among children aged 3-24 months in seven Chinese provinces. Each child received a combination vaccination against diphtheria, tetanus, acellular pertussis, and Haemophilus influenzae type b (DTaP-Hib). Through daily telephone follow-up, we collected AEs within seven days. Oral swab samples were collected to investigate the effects of single nucleotide polymorphisms (SNPs) on the risk of AEs.

RESULTS

304 participants were included in the study. In univariate analysis, we discovered three protective SNPs (rs452204, OR = 0.67, P = 0.0352; rs9282763 and rs839, OR = 0.64, P = 0.0256) and one risk SNP (rs9610, OR = 2.20, P = 0.0397). In multivariate analysis, the effects of rs452204 and rs839 were found to be stable. The interaction between rs452204 and rs9610 was observed (OR = 7.25, 95% CI: 1.44-36.58, P = 0.0165).

CONCLUSION

Genetic predisposition was associated with the risk of AEs after DTaP-Hib vaccination, emphasizing the potential application in the prevention of AEs.

Integrated transcriptomic and regulatory network analyses uncovers the role of let-7b-5p, SPIB, and HLA-DPB1 in sepsis

Sepsis has affected millions of populations of all age groups, locations, and sexes worldwide. Immune systems, either innate or adaptive are dysregulated due to the infection. Various biomarkers are present to date, still sepsis is a primary cause of mortality. Globally, post-operative body infections can cause sepsis and septic shock in ICU. Abnormal antigen presentation to T-cells leads to a dysregulated immune system. miRNAs are sparkly evolved as biomarkers due to their high sensitivity and efficiency. In this work, we analyzed high-throughput mRNA data collected from Gene Expression Omnibus (GEO) and linked it to significant miRNAs and TFs using a network-based approach. Protein–protein interaction (PPI) network was constructed using sepsis-specific differentially expressed genes (DEGs) followed by enrichment analyses and hub module detection. Sepsis-linked decrease transcription of the classical HLA gene such as HLA-DPB1 and its interplay with miR-let-7b-5p and transcription factor SPIB was observed. This study helped to provide innovative targets for sepsis.

Proteomic assessment of humoral immune responses in smallpox vaccine recipients

The availability of effective smallpox vaccines was a critical element of the successful eradication of smallpox in 1980. Antibody responses play a primary role in protective immunity and neutralizing antibody is an established correlate of protection against smallpox. In this study we used a poxvirus proteome array to assess the antibody response to individual viral proteins in a cohort of 1,037 smallpox vaccine recipients. Several statistically significant differences were observed in the antibody response to immunodominant proteins between men and women, including B5R-a major target of neutralizing antibody in vaccinia immune globulin, and the membrane proteins D8L and A27L, both of which have been used as vaccine antigens providing protection in animal models. We also noted differences across racial/ethnic groups. In this cohort, which consisted of both ACAM2000 and Dryvax recipients, we noted minute differences in the antibody responses to a restricted number of viral proteins, providing additional support for the use of ACAM2000 as a replacement smallpox vaccine. Furthermore, our data indicate that poxvirus proteome microarrays can be valuable for screening and monitoring smallpox vaccine-induced humoral immune responses in large-scale serologic surveillance studies and prove useful in the guidance of developing novel smallpox candidate vaccines.

Effect of Serial Passage on the Pathogenicity and Immunogenicity of Vaccinia Virus LC16m8 Strain

The phenotype of an attenuated live vaccine depends on gene mutation achieved by, for example, many passages in cultured cells. Viral clones with preferable phenotypes are selected and the causative genetic mutation(s) are later identified. LC16m8 is an example of a highly attenuated smallpox vaccine that was developed and licensed in Japan in the 1970s. LC16m8 was obtained by the passaging of Lister strain, with indicators of small plaque formation and temperature sensitivity as virus phenotypes. This strain can replicate in mammalian cells and provides robust cellular and humoral immunity, as well as long-term immune memory. Recent studies using proteome-wide antigen arrays have revealed that antibody production against LC16m8 and other VACVs differs largely among individuals. Moreover, associations between SNPs in immune-related genes and immune outcomes have been increasingly found. These results lead to predicting adverse events of a vaccine, which is a purpose of vaccinomics. Studies on VACV will continue to contribute to the understanding of host-pathogen interactions and to development of a vaccine for other infectious and non-infectious diseases. Here, we review studies of VACV, including our recent research on LC16m8, with a focus on the phenotype and genotype, and we discuss future research directions.

Association of single-nucleotide polymorphisms in tumour necrosis factor and human leukocyte antigens genes with type 1 diabetes

Type 1 diabetes (T1D) is an autoimmune disease characterized by progressive destruction of insulin-producing pancreatic beta cells. This multifactorial disease has a strong genetic component associated with the human leukocyte antigens (HLA) and non-HLA regions. In this study, we compared frequencies of HLA-DRB1 alleles and single-nucleotide polymorphisms (SNPs) associated the genes coding for: toll-like receptors (TLRs), tumour necrosis factor (TNF), interleukin-1 (IL-1), interleukin-1 receptor type 1 (IL-1R1), interleukin-1 receptor antagonist (IL-1RN), interleukin-2 (IL-2) and interleukin-12B (IL-12B), between T1D patients and healthy controls. The aim was to identify frequency differences and linkage between these genetic markers in T1D patients and healthy controls. Twelve SNPs were investigated as follows: rs16944 (IL-1B), rs1143634 (IL-1B), rs1800587 (IL-1A), rs2069762 (IL-2), rs3212227 (IL-12B), rs2234650 (IL-1R1), rs315952 (IL-1RN), rs3804099 (TLR2), rs4986790 (TLR4), rs4986791 (TLR4), rs1800629 (TNF) and rs361525 (TNF). TaqMan genotype assay method was used for SNPs genotyping. HLA-DRB1* genes were typed by Sequence Specific Oligonucleotide Probe (SSOP). SPSS and SNPStats programs were used for the statistical analysis. Significant differences between T1D and control groups were found for the dominant model of rs361525 and rs1800629A:rs361525G genotypes for TNF. Increased frequencies of DRB1*03 and DRB1*04 and decreased frequencies of DRB1*07, DRB1*11 and DRB1*13 and DRB1*15 were observed in T1D patients compared with controls. However, the genotype, DRB1*07 with rs1800629A/G was associated with T1D. We have confirmed that DRB1*03 and DRB1*04 are associated with increased risk and DRB1*07, DRB1*11 and DRB1*13 and DRB1*15 with decreased risk of T1D. Also, the dominant model of rs361525A, and the rs1800629G:361525A genotype were associated with increased risk. The simultaneous presence of DRB1*07 and rs1800629A/G genotypes in 23 out of 27 DRB1*07 positive T1D patients implied that islet cell peptide processing may have been biased towards autoimmunity by upregulation of TNF associated intronic SNPs.

Polymorphisms in STING Affect Human Innate Immune Responses to Poxviruses

We conducted a large genome-wide association study (GWAS) of the immune responses to primary smallpox vaccination in a combined cohort of 1,653 subjects. We did not observe any polymorphisms associated with standard vaccine response outcomes (e.g., neutralizing antibody, T cell ELISPOT response, or T cell cytokine production); however, we did identify a cluster of SNPs on chromosome 5 (5q31.2) that were significantly associated (p-value: 1.3 x 10⁻¹² – 1.5x10⁻³⁶) with IFNα response to in vitro poxvirus stimulation. Examination of these SNPs led to the functional testing of rs1131769, a non-synonymous SNP in TMEM173 causing an Arg-to-His change at position 232 in the STING protein—a major regulator of innate immune responses to viral infections. Our findings demonstrate differences in the ability of the two STING variants to phosphorylate the downstream intermediates TBK1 and IRF3 in response to multiple STING ligands. Further downstream in the STING pathway, we observed significantly reduced expression of type I IFNs (including IFNα) and IFN-response genes in cells carrying the H232 variant. Subsequent molecular modeling of both alleles predicted altered ligand binding characteristics between the two variants, providing a potential mechanism underlying differences in inter-individual responses to poxvirus infection. Our data indicate that possession of the H232 variant may impair STING-mediated innate immunity to poxviruses. These results clarify prior studies evaluating functional effects of genetic variants in TMEM173 and provide novel data regarding genetic control of poxvirus immunity.

Current Challenges in Vaccinology

The development of vaccines, which prime the immune system to respond to future infections, has led to global declines in morbidity and mortality from dreadful infectious communicable diseases. However, many pathogens of public health importance are highly complex and/or rapidly evolving, posing unique challenges to vaccine development. Several of these challenges include an incomplete understanding of how immunity develops, host and pathogen genetic variability, and an increased societal skepticism regarding vaccine safety. In particular, new high-dimensional omics technologies, aided by bioinformatics, are driving new vaccine development (vaccinomics). Informed by recent insights into pathogen biology, host genetic diversity, and immunology, the increasing use of genomic approaches is leading to new models and understanding of host immune system responses that may provide solutions in the rapid development of novel vaccine candidates.

Immunosenescence: A systems-level overview of immune cell biology and strategies for improving vaccine responses

Immunosenescence contributes to a decreased capacity of the immune system to respond effectively to infections or vaccines in the elderly. The full extent of the biological changes that lead to immunosenescence are unknown, but numerous cell types involved in innate and adaptive immunity exhibit altered phenotypes and function as a result of aging. These manifestations of immunosenescence at the cellular level are mediated by dysregulation at the genetic level, and changes throughout the immune system are, in turn, propagated by numerous cellular interactions. Environmental factors, such as nutrition, also exert significant influence on the immune system during aging. While the mechanisms that govern the onset of immunosenescence are complex, systems biology approaches allow for the identification of individual contributions from each component within the system as a whole. Although there is still much to learn regarding immunosenescence, systems-level studies of vaccine responses have been highly informative and will guide the development of new vaccine candidates, novel adjuvant formulations, and immunotherapeutic drugs to improve vaccine responses among the aging population.

Association of human leukocyte antigen alleles and supertypes with immunogenicity of oral rotavirus vaccine given to infants in China

Rotavirus (RV) vaccines show distinct immunogenicity in dozens of clinical trials, which is associated with multiple host and environmental factors. Previous research has demonstrated that the highly polymorphic human leukocyte antigen (HLA) system plays an essential role in regulating immune response to a variety of vaccines. This study aims to investigate the relationship between HLA polymorphisms and immunogenicity of RV vaccine.A nested case-control study was carried out among infants enrolled in phase III clinical trial of trivalent human-lamb reassortant vaccine (RV3) in Henan province, China. Serum RV specific immunoglobulin A (RV-IgA) was detected before and after a 3-dose vaccination series, followed by calculation of seroconversion rates. Seroconversion was defined as a 4-fold or greater increase in RV-IgA titers between pre-vaccination and 1-month post-dose 3 vaccination. The infants who seroconverted were defined as responders, and the others without seroconversion were considered as non-responders. Their HLA genotypes were obtained by using the sequence-based typing method. The HLA allele and supertype frequencies of 2 groups were analyzed statistically.Eighty-three of 133 infants seroconverted after vaccination. Twenty-one HLA-A, 45 HLA-B, 24 HLA-Cw, 29 HLA-DRB1 and 16 HLA-DQB1 distinct alleles were detected. The frequency of HLA-B4001 (corrected P = .01, adjusted OR = 0.152, 95% CI = 0.048-0.475) in non-responder group was significantly higher than that in responder group. Furthermore, significant association was found between HLA-B44 supertype (corrected P = .02, adjusted OR = 0.414, 95% CI = 0.225-0.763) and RV non-response.Certain HLA allele (HLA-B4001) and supertype (HLA-B44) are potentially associated with non-response after immunization with the novel RV3 vaccine in Chinese infants.

Tetanus-diphtheria vaccination in adults: the long-term persistence of antibodies is not dependent on polyclonal B-cell activation and the defective response to diphtheria toxoid re-vaccination is associated to HLADRB1∗01

Cellular and humoral immune responses to tetanus-diphtheria vaccine (Td) were assessed in human leukocyte antigen (HLA)-typed Italian military personnel who received multiple concomitant vaccines. Td-specific antibodies and T-lymphocytes were measured in individuals with one (group-1) and more than one (group-2) Td boosters. A third group (group-3), who received several vaccines, but not Td, was studied to verify the hypothesis of the polyclonal B-cell activation as mechanism for antibody persistence. The antibody response to Td toxoids was higher in group-1, who showed lower baseline antibody levels, than in group-2 subjects. The antibody response to tetanus was higher than to diphtheria toxoid in both groups. No correlation between antibody and cellular response, and no interference in the response to Td by co-administration of different vaccines were observed. HLA-DRB1∗01 allele was detected at significant higher frequency in subjects unable to double the baseline anti-diphtheria antibody levels after the vaccination. Anti-tetanus and diphtheria antibodies half-lives were assessed and the long-lasting persistence above the threshold for protection (0.1 IU/ml) was estimated in over 65 and 20 years, respectively. No significant increase of anti-diphtheria antibodies was observed in consequence of polyclonal B-cell activation. This study emphasizes the duration of Td vaccination-induced seroprotection, suggesting that re-vaccination should probably be performed at intervals longer than 10 years. No reciprocal interference by concomitantly administered vaccines has been observed. HLA-DRB1∗01 allele was significantly associated with anti-diphtheria defective response. Finally, this study does not confirm that anti-diphtheria antibody levels are maintained by polyclonal B-cell activation. Clinical trial registry: The study was registered with NCT01807780.

Genome-wide associations of CD46 and IFI44L genetic variants with neutralizing antibody response to measles vaccine

Population-based studies have revealed 2-10% measles vaccine failure rate even after two vaccine doses. While the mechanisms behind this remain unknown, we hypothesized that host genetic factors are likely to be involved. We performed a genome-wide association study of measles specific neutralizing antibody and IFNγ ELISPOT response in a combined sample of 2872 subjects. We identified two distinct chromosome 1 regions (previously associated with MMR-related febrile seizures), associated with vaccine-induced measles neutralizing antibody titers. The 1q32 region contained 20 significant SNPs in/around the measles virus receptor-encoding CD46 gene, including the intronic rs2724384 (p value = 2.64 × 10^-09) and rs2724374 (p value = 3.16 × 10^-09) SNPs. The 1q31.1 region contained nine significant SNPs in/around IFI44L, including the intronic rs1333973 (p value = 1.41 × 10^-10) and the missense rs273259 (His73Arg, p value = 2.87 × 10^-10) SNPs. Analysis of differential exon usage with mRNA-Seq data and RT-PCR suggests the involvement of rs2724374 minor G allele in the CD46 STP region exon B skipping, resulting in shorter CD46 isoforms. Our study reveals common CD46 and IFI44L SNPs associated with measles-specific humoral immunity, and highlights the importance of alternative splicing/virus cellular receptor isoform usage as a mechanism explaining inter-individual variation in immune response after live measles vaccine.

Heritability of vaccine-induced measles neutralizing antibody titers

Understanding how genetics influences inter-individual variation of antibody titers in response to measles vaccination is vital to understanding possible sources of vaccine failure as well as improved vaccine development. Although it is recognized that both the human leukocyte antigen (HLA) genes and the immunoglobulin allotype genes play significant roles in immune response, there is significant variation in antibody titers that is not explained by these genes. To obtain a more complete estimate of the role of the entire genome, we used a large panel of single nucleotide polymorphisms to estimate the heritability of antibody response to measles vaccine. Based on 935 subjects with European ancestry, we estimated the heritability to be 49% (standard error 0.17). We also estimated the heritability attributable to each chromosome, and found a large range in chromosome-specific heritabilities. Notably, chromosome 1 had the largest estimate (28%), while chromosome 6, which harbors HLA, had an estimated heritability of 13%. Compared with a prior study of twins in the same community, which resulted in a heritability estimate of 88.5%, our study suggests there are either many rare genetic variants, or many common genetic variants of small effect sizes that contribute to variations of antibody titers in response to measles vaccine.

Immunoglobulin GM and KM genes and measles vaccine-induced humoral immunity

Identifying genetic polymorphisms that explain variations in humoral immunity to live measles virus vaccine is of great interest. Immunoglobulin GM (heavy chain) and KM (light chain) allotypes are genetic markers known to be associated with susceptibility to several infectious diseases. We assessed associations between GM and KM genotypes and measles vaccine humoral immunity (neutralizing antibody titers) in a combined cohort (n=1796) of racially diverse healthy individuals (age 18-41years). We did not discover any significant associations between GM and/or KM genotypes and measles vaccine-induced neutralizing antibody titers. African-American subjects had higher neutralizing antibody titers than Caucasians (1260mIU/mL vs. 740mIU/mL, p=7.10×10^-13), and those titers remained statistically significant (p=1.68×10^-09) after adjusting for age at enrollment and time since last vaccination. There were no statistically significant sex-specific differences in measles-induced neutralizing antibody titers in our study (p=0.375). Our data indicate a surprising lack of evidence for an association between GM and KM genotypes and measles-specific neutralizing antibody titers, despite the importance of these immune response genes.

A large population-based association study between HLA and KIR genotypes and measles vaccine antibody responses

Human antibody response to measles vaccine is highly variable in the population. Host genes contribute to inter-individual antibody response variation. The killer cell immunoglobulin-like receptors (KIR) are recognized to interact with HLA molecules and possibly influence humoral immune response to viral antigens. To expand on and improve our previous work with HLA genes, and to explore the genetic contribution of KIR genes to the inter-individual variability in measles vaccine-induced antibody responses, we performed a large population-based study in 2,506 healthy immunized subjects (ages 11 to 41 years) to identify HLA and KIR associations with measles vaccine-induced neutralizing antibodies. After correcting for the large number of statistical tests of allele effects on measles-specific neutralizing antibody titers, no statistically significant associations were found for either HLA or KIR loci. However, suggestive associations worthy of follow-up in other cohorts include B*57:01, DQB1*06:02, and DRB1*15:05 alleles. Specifically, the B*57:01 allele (1,040 mIU/mL; p = 0.0002) was suggestive of an association with lower measles antibody titer. In contrast, the DQB1*06:02 (1,349 mIU/mL; p = 0.0004) and DRB1*15:05 (2,547 mIU/mL; p = 0.0004) alleles were suggestive of an association with higher measles antibodies. Notably, the associations with KIR genotypes were strongly nonsignificant, suggesting that KIR loci in terms of copy number and haplotypes are not likely to play a major role in antibody response to measles vaccination. These findings refine our knowledge of the role of HLA and KIR alleles in measles vaccine-induced immunity.

A time transect of exomes from a Native American population before and after European contact

A major factor for the population decline of Native Americans after European contact has been attributed to infectious disease susceptibility. To investigate whether a pre-existing genetic component contributed to this phenomenon, here we analyse 50 exomes of a continuous population from the Northwest Coast of North America, dating from before and after European contact. We model the population collapse after European contact, inferring a 57% reduction in effective population size. We also identify signatures of positive selection on immune-related genes in the ancient but not the modern group, with the strongest signal deriving from the human leucocyte antigen (HLA) gene HLA-DQA1. The modern individuals show a marked frequency decrease in the same alleles, likely due to the environmental change associated with European colonization, whereby negative selection may have acted on the same gene after contact. The evident shift in selection pressures correlates to the regional European-borne epidemics of the 1800s.

A First Nation population declined after European contact, likely as a result of infectious disease. Here, researchers partner with indigenous communities to analyse ancient and modern Native American exomes, and find a shift in selection pressure on immune genes, correlated to European-borne epidemics.

Genetically defined race, but not sex, is associated with higher humoral and cellular immune responses to measles vaccination

In addition to host genetic and environmental factors, variations in immune responses to vaccination are influenced by demographic variables, such as race and sex. The influence of genetic race and sex on measles vaccine responses is not well understood, yet important for the development of much-needed improved measles vaccines with lower failure rates. We assessed associations between genetically defined race and sex with measles humoral and cellular immunity after measles vaccination in three independent and geographically distinct cohorts totaling 2872 healthy racially diverse children, older adolescents, and young adults. We found no associations between biological sex and either humoral or cellular immunity to measles vaccine, and no correlation between humoral and cellular immunity in these study subjects. Genetically defined race was, however, significantly associated with both measles vaccine-induced humoral and cellular immune responses, with subjects genetically classified as having African-American ancestry demonstrating significantly higher antibody and cell-mediated immune responses relative to subjects of Caucasian ancestry. This information may be useful in designing novel measles vaccines that are optimally effective across human genetic backgrounds.

Statistical Methods for Testing Genetic Pleiotropy

Genetic pleiotropy is when a single gene influences more than one trait. Detecting pleiotropy and understanding its causes can improve the biological understanding of a gene in multiple ways, yet current multivariate methods to evaluate pleiotropy test the null hypothesis that none of the traits are associated with a variant; departures from the null could be driven by just one associated trait. A formal test of pleiotropy should assume a null hypothesis that one or no traits are associated with a genetic variant. For the special case of two traits, one can construct this null hypothesis based on the intersection-union (IU) test, which rejects the null hypothesis only if the null hypotheses of no association for both traits are rejected. To allow for more than two traits, we developed a new likelihood-ratio test for pleiotropy. We then extended the testing framework to a sequential approach to test the null hypothesis that [Formula: see text] traits are associated, given that the null of k traits are associated was rejected. This provides a formal testing framework to determine the number of traits associated with a genetic variant, while accounting for correlations among the traits. By simulations, we illustrate the type I error rate and power of our new methods; describe how they are influenced by sample size, the number of traits, and the trait correlations; and apply the new methods to multivariate immune phenotypes in response to smallpox vaccination. Our new approach provides a quantitative assessment of pleiotropy, enhancing current analytic practice.

HLA Polymorphism in Algerian Children With Lymphomas

BACKGROUND

Non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL) are the 2 types of lymphoma that represent the third most common childhood malignancy. Multiple etiological factors are involved in lymphoma pathogenesis, including viral infection, immune deficiencies, environmental agents, and genetic factors. Strong arguments supporting a genetic linkage between the susceptibility to lymphomas and human leukocyte antigens (HLA) are reported and give an idea about susceptibility or protection from the disease.

METHODS

Seventy-one cases were included in this study: 36 cases of non-Hodgkin lymphoma and 35 patients with Hodgkin lymphoma. Their ages ranged from 4 to 18 years. The control group consisted of 70 unrelated healthy individuals, with a mean age of 5 to 17 years. The genotype of HLA-A, HLA-B, HLA-DR, and HLA-DQ alleles was typed by means of PCR sequence-specific priming.

RESULTS

HLA-B*18, HLA-DRB1*03, *07, and HLA-DQB1*02 were significantly increased in patients with lymphomas when compared with controls, whereas HLA-DRB1*13 and DQB1*03 were significantly decreased when compared with controls.

CONCLUSIONS

These results indicate that HLA-B*18, DRB1*03, *07, and DQB1*02 may contribute to lymphoma susceptibility, whereas HLA-DRB1*13 and DQB1*03 may confer protection to lymphoma in the Algerian population.

Fine Mapping Causal Variants with an Approximate Bayesian Method Using Marginal Test Statistics

Two recently developed fine-mapping methods, CAVIAR and PAINTOR, demonstrate better performance over other fine-mapping methods. They also have the advantage of using only the marginal test statistics and the correlation among SNPs. Both methods leverage the fact that the marginal test statistics asymptotically follow a multivariate normal distribution and are likelihood based. However, their relationship with Bayesian fine mapping, such as BIMBAM, is not clear. In this study, we first show that CAVIAR and BIMBAM are actually approximately equivalent to each other. This leads to a fine-mapping method using marginal test statistics in the Bayesian framework, which we call CAVIAR Bayes factor (CAVIARBF). Another advantage of the Bayesian framework is that it can answer both association and fine-mapping questions. We also used simulations to compare CAVIARBF with other methods under different numbers of causal variants. The results showed that both CAVIARBF and BIMBAM have better performance than PAINTOR and other methods. Compared to BIMBAM, CAVIARBF has the advantage of using only marginal test statistics and takes about one-quarter to one-fifth of the running time. We applied different methods on two independent cohorts of the same phenotype. Results showed that CAVIARBF, BIMBAM, and PAINTOR selected the same top 3 SNPs; however, CAVIARBF and BIMBAM had better consistency in selecting the top 10 ranked SNPs between the two cohorts. Software is available at https://bitbucket.org/Wenan/caviarbf.

Adversomics: a new paradigm for vaccine safety and design

Despite the enormous population benefits of routine vaccination, vaccine adverse events (AEs) and reactions, whether real or perceived, have posed one of the greatest barriers to vaccine acceptance--and thus to infectious disease prevention--worldwide. A truly integrated clinical, translational, and basic science approach is required to understand the mechanisms behind vaccine AEs, predict them, and then apply this knowledge to new vaccine design approaches that decrease, or avoid, these events. The term 'adversomics' was first introduced in 2009 and refers to the study of vaccine adverse reactions using immunogenomics and systems biology approaches. In this review, we present the current state of adversomics research, review known associations and mechanisms of vaccine AEs/reactions, and outline a plan for the further development of this emerging research field.

Systems vaccinology: Enabling rational vaccine design with systems biological approaches

Vaccines have drastically reduced the mortality and morbidity of many diseases. However, vaccines have historically been developed empirically, and recent development of vaccines against current pandemics such as HIV and malaria has been met with difficulty. The advent of high-throughput technologies, coupled with systems biological methods of data analysis, has enabled researchers to interrogate the entire complement of a variety of molecular components within cells, and characterize the myriad interactions among them in order to model and understand the behavior of the system as a whole. In the context of vaccinology, these tools permit exploration of the molecular mechanisms by which vaccines induce protective immune responses. Here we review the recent advances, challenges, and potential of systems biological approaches in vaccinology. If the challenges facing this developing field can be overcome, systems vaccinology promises to empower the identification of early predictive signatures of vaccine response, as well as novel and robust correlates of protection from infection. Such discoveries, along with the improved understanding of immune responses to vaccination they impart, will play an instrumental role in development of the next generation of rationally designed vaccines.