Background

Immigrants represented 21.8% of cases in a Spanish cohort of hospitalised patients with COVID-19, a proportion exceeding the percentage of immigrants in that area’s total population. Among the ethnic-related genetic risk factors for COVID-19, human leukocyte antigen (HLA) genotypes in diverse populations might bias the response to SARS-CoV-2 infection and/or progression. Similarly, genetic differences in natural killer-activating and inhibitory receptors could play a role in the immune system’s response to the viral infection.

Methods

We characterised HLA alleles and KIR genes in 52 Ecuadorian patients hospitalised for moderate and severe COVID-19 and 87 Ecuadorian controls from the general population living in the same area.

Results

There was a significantly increased frequency of the HLA-B*39 antigen and the activating KIR2DS4 receptor in the presence of its HLA-C*04 ligand in the COVID-19 group when compared with the control group. In contrast, there was a significant reduction in the frequency of carriers of KIR2DL1 and of the KIR3DL1/Bw4 receptor/ligand combination among COVID-19 group. On the other hand, HLA-A*24:02 and HLA-DRB1*09:01 alleles showed significantly lower frequencies specifically in the severe COVID-19 group.

Conclusion

HLA-B*39 alleles might be genetic risk factors for developing COVID-19 in Ecuadorian individuals. In the presence of its ligand C*04, the natural killer-activating receptor KIR2DS4 might also increase the risk of developing COVID-19, while, in the presence of HLA-Bw4 alleles, the inhibitory receptor KIR3DL1 might play a protective role. Patients with COVID-19 who carry HLA-A*24:02 and HLA-DRB1*09:01 alleles might be protected against more severe forms of COVID-19.

中文翻译：

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居住在马德里的厄瓜多尔患者冠状病毒 19 疾病风险和与 HLA/KIR 多态性相关的保护因素

背景

在西班牙住院的 COVID-19 患者队列中，移民占病例的 21.8%，这一比例超过了移民在该地区总人口中的百分比。在 COVID-19 的种族相关遗传风险因素中，不同人群的人类白细胞抗原 (HLA) 基因型可能会影响对 SARS-CoV-2 感染和/或进展的反应。同样，自然杀伤激活和抑制受体的遗传差异可能在免疫系统对病毒感染的反应中发挥作用。

方法

我们对 52 名因中度和重度 COVID-19 住院的厄瓜多尔患者以及居住在同一地区的普通人群的 87 名厄瓜多尔对照患者的 HLA 等位基因和 KIR 基因进行了特征分析。

结果

与对照组相比，在 COVID-19 组中，在 HLA-C*04 配体存在的情况下，HLA-B*39 抗原和激活 KIR2DS4 受体的频率显着增加。相比之下，COVID-19 组中 KIR2DL1 和 KIR3DL1/Bw4 受体/配体组合的携带者频率显着降低。另一方面，HLA-A*24:02 和 HLA-DRB1*09:01 等位基因的频率显着降低，特别是在重症 COVID-19 组中。

结论

HLA-B*39 等位基因可能是厄瓜多尔人患上 COVID-19 的遗传风险因素。在其配体 C*04 存在的情况下，自然杀伤激活受体 KIR2DS4 也可能会增加患 COVID-19 的风险，而在 HLA-Bw4 等位基因存在的情况下，抑制性受体 KIR3DL1 可能会发挥保护作用。携带 HLA-A*24:02 和 HLA-DRB1*09:01 等位基因的 COVID-19 患者可能会免受更严重形式的 COVID-19 的感染。