Umbilical Cord-derived Mesenchymal Stem Cells modulate TNF and soluble TNF Receptor 2 (sTNFR2) in COVID-19 ARDS patients

OBJECTIVE: We aimed at explaining the mechanism of therapeutic effect of Umbilical Cord Mesenchymal Stem Cells (UCMSC) in subjects with COVID-19 Acute Respiratory Distress Syndrome (ARDS). Patients with COVID-19 ARDS present with a hyperinflammatory response characterized by high levels of circulating pro-inflammatory mediators, including tumor necrosis factor alpha and beta (TNF alpha and TNFB). Inflammatory functions of these TNFs can be inhibited by soluble TNF Receptor 2 (sTNFR2). In patients with COVID-19 ARDS, UCMSC appear to impart a robust anti-inflammatory effect, and treatment is associated with remarkable clinical improvements. We investigated the levels of TNF alpha, INF beta and sTNFR2 in blood plasma samples collected from subjects with COVID-19 ARDS enrolled in our trial of UCMSC treatment. PATIENTS AND METHODS: We analyzed plasma samples from subjects with COVID-19 ARDS (n=24) enrolled in a Phase 1/2a randomized controlled trial of UC-MSC treatment. Plasma samples were obtained at Day 0 (baseline, before UC-MSC or control infusion), and Day 6 post infusion. Plasma concentrations of sTNFR2, TNF alpha, and TNF beta were evaluated using a quantitative multiplex protein array. RESULTS: Our data indicate that at Day 6 after infusion, UC-MSC recipients develop significantly increased levels of plasma sTNFR2 and significantly decreased levels of TNF alpha and TNF beta, compared to controls. CONCLUSIONS: These observations suggest that sTNFR2 plays a mechanistic role in mediating UC-MSC effect on TNF alpha and TNF beta plasma levels, determining a decrease in inflammation in COVID-19 ARDS.

Automated summary

This study aimed to elucidate the therapeutic effect mechanism of Umbilical Cord Mesenchymal Stem Cells (UCMSC) in patients with COVID-19 Acute Respiratory Distress Syndrome (ARDS). Results showed that UCMSC treatment led to significantly increased levels of plasma sTNFR2 and decreased levels of TNF alpha and TNF beta, indicating a decrease in inflammation in COVID-19 ARDS.