RESUMO
BackgroundWe previously reported inborn errors of TLR3- and TLR7-dependent type I interferon (IFN) immunity in 1-5% of unvaccinated patients with life-threatening COVID-19, and auto-antibodies against type I IFN in another 15-20% of cases. MethodsWe report here a genome-wide rare variant burden association analysis in 3,269 unvaccinated patients with life-threatening COVID-19 (1,301 previously reported and 1,968 new patients), and 1,373 unvaccinated SARS-CoV-2-infected individuals without pneumonia. A quarter of the patients tested had antibodies against type I IFN (234 of 928) and were excluded from the analysis. ResultsNo gene reached genome-wide significance. Under a recessive model, the most significant gene with at-risk variants was TLR7, with an OR of 27.68 (95%CI:1.5-528.7, P=1.1x10-4), in analyses restricted to biochemically loss-of-function (bLOF) variants. We replicated the enrichment in rare predicted LOF (pLOF) variants at 13 influenza susceptibility loci involved in TLR3-dependent type I IFN immunity (OR=3.70 [95%CI:1.3-8.2], P=2.1x10-4). Adding the recently reported TYK2 COVID-19 locus strengthened this enrichment, particularly under a recessive model (OR=19.65 [95%CI:2.1-2635.4]; P=3.4x10-3). When these 14 loci and TLR7 were considered, all individuals hemizygous (n=20) or homozygous (n=5) for pLOF or bLOF variants were patients (OR=39.19 [95%CI:5.2-5037.0], P=4.7x10-7), who also showed an enrichment in heterozygous variants (OR=2.36 [95%CI:1.0-5.9], P=0.02). Finally, the patients with pLOF or bLOF variants at these 15 loci were significantly younger (mean age [SD]=43.3 [20.3] years) than the other patients (56.0 [17.3] years; P=1.68x10-5). ConclusionsRare variants of TLR3- and TLR7-dependent type I IFN immunity genes can underlie life-threatening COVID-19, particularly with recessive inheritance, in patients under 60 years old.
RESUMO
BackgroundAlthough the many aspects of COVID-19 have not been yet recognized, it seems that the dysregulation of the immune system has a very important role in the progression of the disease. In this study the lymphocyte subsets were evaluated in COVID-19 patients with different severity. MethodsIn this prospective study, the levels of peripheral lymphocyte subsets (CD3+, CD4+, CD8+ T cells; CD19+ and CD20+ B cells; CD16+/CD56+ NK cells, and CD4+/CD25+/FOXP3+ regulatory T cells) were measured in 67 confirmed patients with COVID-19 on the first day of admission. ResultsThe mean age of cases was 51.3 {+/-} 14.8 years. Thirty-two patients (47.8%) were classified as severe cases and 11 (16.4%) patients were categorized as critical. The frequency of blood lymphocytes, CD3+ cells, CD25+FOXP3+ T cells; and absolute count of CD3+ T cells, CD25+FOXP3+ T cells, CD4+ T cells, CD8+ T cells, CD16+56+ lymphocytes were lower in more severe cases in comparison to milder cases. Percentages of lymphocytes, T cells, and NK cells were significantly lower inthe patients who died (p= 0.002 and P= 0.042, p=0.006, respectively). ConclusionFindings of this cohort study suggests that the frequency of CD4+, CD8+, CD25+FOXP3+ T cells, and NK cells were difference in the severe COVID-19 patients. Moreover, lower frequency of, T cells, and NK cells are predictors of mortality of these patients.