Transcriptome analysis of PBMCs reveals distinct immune response in the asymptomatic and re-detectable positive COVID-19 patients (preprint)

The existence of asymptomatic and re-detectable positive COVID-19 patients presents the disease control challenges of COVID-19. Most studies on immune response of COVID-19 have focused on the moderately or severely symptomatic patients, however little is known about the immune response in asymptomatic and re-detectable positive patients. Here we performed a comprehensive analysis of the transcriptomic profiles of PBMCs from 48 COVID-19 patients which include 8 asymptomatic, 13 symptomatic, 15 recovering and 12 RP patients. Our analysis revealed a down-regulation of IFN response and complement activation in the asymptomatic patients compared with the symptomatic, indicating a weaker immune response of the PBMCs in the asymptomatic patients. In addition, we observed a lower expression of the cytokines and chemokines in the PBMC of asymptomatic and symptomatic patients. In contrast, the cytokines and chemokines level in the RP patients are higher than the recovering. GSEA analysis showed the enrichment of TNFa/NF-{kappa}B and influenza infection in the RP patients compared with the recovering patients, indicating a flu-like, hyper-inflammatory immune response in the PBMC of RP patients. Thus our findings could extend our understanding of host immune response during the progression COVID-19 disease and help the clinical management and the immunotherapy development for COVID-19.

T-cell Repertoire Characteristics of Asymptomatic and Re-detectable Positive COVID-19 Patients (preprint)

Background: The prevention of COVID-19 pandemic is highly complicated by the prevalence of asymptomatic and recurrent infection. Many previous immunological studies have focused on symptomatic and convalescent patients, while the immune responses in asymptomatic patients and re-detectable positive cases remain unclear. Methods: Here we comprehensively analyzed the peripheral T-cell receptor (TCR) repertoire of 54 COVID-19 patients in different phases, including asymptomatic, symptomatic, convalescent and re-detectable positive cases. Results: We found progressed immune responses from asymptomatic to symptomatic phase. Furthermore, the TCR profiles of re-detectable positive cases were highly similar to those of asymptomatic patients, which could predict the risk of recurrent infection. Conclusion: Therefore, TCR repertoire surveillance has the potential to strengthen the clinical management and the immunotherapy development for COVID-19.