An in Silico Scientific Basis for LL-37 as a Therapeutic and Vitamin D as Preventive for Covid-19.

Even as clinical trials are underway for vaccines and therapeutics for Covid-19, establishment of modalities with a strong and complete foundation is still awaited and until then, the uncertainty remains associated. Thus, there is a requirement to research as many new and different types of approaches as possible to tackle the pandemic. In this report, in silico scientific findings are presented, which are indicative of the putative potential for the use of the LL-37 human anti-microbial peptide as a therapeutic or possibly even as a prophylactic against SARS-CoV-2. This indication is mainly based on the high structural similarity of LL-37 to the N-terminal helix of the receptor-binding domain of SARS-CoV-2, and the positive prediction of binding of LL-37 to the receptor-binding domain of SARS-CoV-2. Also, as Vitamin D is known to upregulate the expression of LL-37, the vitamin is a candidate preventive molecule. This report also provides the possible basis for why there is an inverse correlation between Vitamin D levels in the body and the severity of or susceptibility to Covid-19, as described in a large body of published literature. The path for development of LL-37 as a therapeutic could be of lesser duration, as LL-37 is native to the human body. With the scientific link put forth in this work, Vitamin D could be used at an effective, medically prescribed dose as a preventive measure. As Vitamin D is insoluble in water, it should be taken only in consultation with a medical practitioner to prevent adverse effects of its accumulation in the body. The information in this report would be valuable in bolstering the worldwide efforts to control the pandemic as early as possible.