Sustained expression of inflammatory monocytes and activated T cells in COVID-19 patients and recovered convalescent plasma donors

Intense monocyte activation and infiltration into the target tissues is the main mechanism of lung injury in SARS CoV2 infection. A reduction in the degree and nature of such cellular responses is expected following recovery. We aimed to investigate the immune responses in severe Covid-19 patients and recovered patients. MethodsSevere COVID-19 patients (n=34) at Lok Nayak Hospital, New Delhi and COVID-19 recovered patients (n=15) from mild disease and considered for convalescent plasma (COPLA) donation at Institute of Liver and Biliary Sciences (ILBS), New Delhi were recruited. We performed a multiplex cytokine bead assay in plasma and detailed multicolour flow cytometric analysis in peripheral blood of both groups and outcomes were compared in both groups and with healthy controls (n=10). ResultsA significant increase in inflammatory markers [MIP1-a, MIP3a, MCP1, MIF, MMP12, ITAC, VEGF-A, and leptin] was observed in severe patients. Non-survivors additionally showed increased IL-6 levels. Despite the sustained expression of MIPs, the recovered patients showed a surge in MCSF and IL-18 levels. Both the groups had increased CCR2, CX3CR1 positive monocytes, low CD8 T cells, APRIL and BAFFR+ve B cells compared with healthy subjects. In conclusion, patients who have recovered and considered for COPLA donations still have compromised immunity with sustained expression of inflammatory monocytes and activated T cells.

Multi-Omics integration analysis of respiratory specimen characterizes baseline molecular determinants associated with COVID-19 diagnosis.

Rapid diagnosis and precise prognostication of SARS-CoV-2 infection remains a major challenge. A multi-omic approach was adopted, and in the discovery phase, global proteome/metaproteome/metabolome were analysed in the respiratory specimens of SARS-CoV-2 positive [n=20], negative [n=20], and H1N1 positive [n=5] cases. We identified MX1 (MX Dynamin Like GTPase 1) and WARS (Tryptophan--tRNA ligase) as clues to viral diagnosis and validated in 200 SARS-CoV-2 suspects. MX1 >30pg/ml and WARS >25ng/ml segregated virus positives patients [(AUC=94%CI(0.91-0.97)]. Distinct increase in SARS-CoV-2 induced immune activation, metabolic reprograming and a decrease in oxygen transport, wound healing, fluid regulation, vitamin and steroid metabolism was seen (p<0.05). Multi-omics profiling correlated with viraemia and segregated asymptomatic COVID-19 patients. Additionally, the multiomics approach identified increased respiratory pathogens [Burkholderiales, Klebsiella pneumonia] and decreased lactobacillus salivarius (FDR<0.05, p<0.05) in COVID-19 specimens. ConclusionNovel proteins [MX1 and WARS] can rapidly and reliably diagnose SARS-CoV-2 infection and identify asymptomatic and mild disease.