Schoeman Dewald, Fielding Burtram C
Molecular Biology and Virology Research Laboratory, Department of Medical Biosciences, University of the Western Cape, Bellville, Cape Town, Western Cape, South Africa.
Molecular Biology and Virology Research Laboratory, Department of Medical Biosciences, University of the Western Cape, Bellville, Cape Town, Western Cape, South Africa
mSphere. 2021 May 12;6(3):e00031-21. doi: 10.1128/mSphere.00031-21.
In much of the developing world, severe malnutrition is the most prevalent cause of immunodeficiency and affects up to 50% of the population in some impoverished communities. As yet, we do not know how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) will behave in populations with immunodeficiency caused by malnourishment. Interestingly, researchers are now speculating that, in some instances, a defective cellular immune system could paradoxically be a protective factor against severe disease in certain patients contracting SARS-CoV and SARS-CoV-2. This could be linked to the absence of T-cell activation. Based on available information presented here, it is plausible that the hyperimmune response, and subsequent cytokine storm often associated with severe coronavirus disease 2019 (COVID-19), could be "counteracted" by the defective immune response seen in individuals with malnutrition-induced leptin deficiency. In this paper, we proposed a theory that although those with malnutrition-linked leptin deficiency are at risk of SARS-CoV-2 infection, they are at lower risk of developing severe COVID-19.
在许多发展中世界地区，严重营养不良是免疫缺陷最普遍的原因，在一些贫困社区影响高达50%的人口。目前，我们尚不清楚严重急性呼吸综合征冠状病毒2（SARS-CoV-2）在因营养不良导致免疫缺陷的人群中会有怎样的表现。有趣的是，研究人员现在推测，在某些情况下，有缺陷的细胞免疫系统可能反常地成为某些感染SARS-CoV和SARS-CoV-2的患者抵御重症疾病的一个保护因素。这可能与T细胞激活的缺失有关。基于此处提供的现有信息，营养不良诱导的瘦素缺乏个体中出现的有缺陷的免疫反应有可能“抵消”通常与严重的2019冠状病毒病（COVID-19）相关的超免疫反应及随后的细胞因子风暴。在本文中，我们提出了一个理论，即尽管那些因营养不良而瘦素缺乏的人有感染SARS-CoV-2的风险，但他们患重症COVID-19的风险较低。
