Human Leukocyte Antigen Susceptibility Map for Severe Acute Respiratory Syndrome Coronavirus 2


Genetic variability across the three major histocompatibility complex (MHC) class I genes (human leukocyte antigen A [HLA-A], -B, and -C genes) may affect susceptibility to and severity of the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for coronavirus disease 2019 (COVID-19). We performed a comprehensive in silico analysis of viral peptide-MHC class I binding affinity across 145 HLA-A, -B, and -C genotypes for all SARS-CoV-2 peptides. We further explored the potential for cross-protective immunity conferred by prior exposure to four common human coronaviruses. The SARS-CoV-2 proteome was successfully sampled and was represented by a diversity of HLA alleles. However, we found that HLA-B*46:01 had the fewest predicted binding peptides for SARS-CoV-2, suggesting that individuals with this allele may be particularly vulnerable to COVID-19, as they were previously shown to be for SARS (M. Lin, H.-T. Tseng, J. A. Trejaut, H.-L. Lee, et al., BMC Med Genet 4:9, 2003, https://bmcmedgenet.biomedcentral.com/articles/10.1186/1471-2350-4-9). Conversely, we found that HLA-B*15:03 showed the greatest capacity to present highly conserved SARS-CoV-2 peptides that are shared among common human coronaviruses, suggesting that it could enable cross-protective T-cell-based immunity. Finally, we reported global distributions of HLA types with potential epidemiological ramifications in the setting of the current pandemic.

IMPORTANCE Individual genetic variation may help to explain different immune responses to a virus across a population. In particular, understanding how variation in HLA may affect the course of COVID-19 could help identify individuals at higher risk from the disease. HLA typing can be fast and inexpensive. Pairing HLA typing with COVID-19 testing where feasible could improve assessment of severity of viral disease in the population. Following the development of a vaccine against SARS-CoV-2, the virus that causes COVID-19, individuals with high-risk HLA types could be prioritized for vaccination.

Breast-feeding not linked to type 1 diabetes in high-risk population.


An analysis of data from children enrolled in the MIDIA study indicates no association between breast-feeding and the risk for developing type 1 diabetes or autoislet autoimmunity.

Multivariate analysis of the data showed that the only variable linked to type 1 diabetes or autoislet immunity was having a first-degree relative with type 1 diabetes (P<.001). After adjustment for this factor, researchers found no significant association between development of type 1 diabetes and full breast-feeding (OR=1.28; P=.66) or any breast-feeding (OR=1.01; P=.99). Similar results were noted for full breast-feeding (OR=1.3; P=.41) or any breast-feeding (OR=1.25; P=.51) and islet autoimmunity.

For the study, the researchers assessed data from the MIDIA prospective cohort study, which included children with the high-risk human leukocyte antigen (HLA) genotype. Of 48,000 children genotyped, 1,047 had the high-risk HLA genotype. At 3, 6, 9 and 12 months of age, parents filled out questionnaires and the researchers obtained blood samples from the children. Full and any breast-feeding were defined using WHO criteria, and logistic regression analyses were used to identify the relationship between type 1 diabetes and islet autoimmunity and full or any breast-feeding and parent or infant characteristics.

Source: Endocrine Today.