ABSTRACT
Genetic polymorphisms at the IFNL4 loci are known to influence the clinical outcome of several different infectious diseases. Best described is the association between the IFNL4 genotype and hepatitis C virus clearance. However, an influence of the IFNL4 genotype on the adaptive immune system was suggested by several studies but never investigated in humans. In this cross-sectional study, we have genotyped 201 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive participants for 3 IFNL4 polymorphisms (rs368234815, rs12979860, and rs117648444) and stratified them according to the IFNλ4 activity. Based on this stratification, we investigated the association between the IFNL4 genotype and the antibody as well as the CD8+ T cell response in the acute phase of the SARS-CoV-2 infection. We observed no differences in the genotype distribution compared with a Danish reference cohort or the 1,000 Genome Project, and we were not able to link the IFNL4 genotype to changes in either the antibody or CD8+ T cell responses of these patients.
Subject(s)
Adaptive Immunity/immunology , COVID-19/immunology , Interleukins/immunology , SARS-CoV-2/immunology , Adaptive Immunity/genetics , Adult , Aged , CD8-Positive T-Lymphocytes/immunology , Cohort Studies , Cross-Sectional Studies , Female , Genotype , Humans , Interleukins/genetics , Male , Middle Aged , Polymorphism, Single Nucleotide/genetics , Polymorphism, Single Nucleotide/immunology , SARS-CoV-2/genetics , Young AdultABSTRACT
BACKGROUND: The recent pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has elevated several clinical and scientific questions. These include how host genetic factors influence the pathogenesis and disease susceptibility. Therefore, the aim of this study was to evaluate the impact of interferon lambda 3 and 4 (IFNL3/4) gene polymorphisms and clinical parameters on the resistance and susceptibility to coronavirus disease 2019 (COVID-19) infection. METHODS: A total of 750 SARS-CoV-2 positive patients (375 survivors and 375 nonsurvivors) were included in this study. All single-nucleotide polymorphisms (SNPs) on IFNL3 (rs12979860, rs8099917, and rs12980275) and IFNL4 rs368234815 were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: In this study, a higher viral load (low PCR Ct value) was shown in nonsurvivor patients. In survivor patients, the frequency of the favorable genotypes of IFNL3/4 SNPs (rs12979860 CC, rs12980275 AA, rs8099917 TT, and rs368234815 TT/TT) was significantly higher than in nonsurvivor patients. Multivariate logistic regression analysis has shown that a higher low-density lipoprotein (LDL), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and PCR Ct value, and lower 25-hydroxyvitamin D, and also IFNL3 rs12979860 TT, IFNL3 rs8099917 GG, IFNL3 rs12980275 GG, and IFNL4 rs368234815 ∆G/∆G genotypes were associated with the severity of COVID-19 infection. CONCLUSIONS: The results of this study proved that the severity of COVID-19 infection was associated with clinical parameters and unfavorable genotypes of IFNL3/IFNL4 SNPs. Further studies in different parts of the world are needed to show the relationship between severity of COVID-19 infection and host genetic factors.