Post by Nadica (She/Her) on Jul 28, 2024 2:35:50 GMT
The putative mechanism of lymphopenia in COVID-19 patients - Published May 31, 2022
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants have caused >500 million confirmed cases and >6 million deaths. Apart from the common clinical manifestations, 63% of admitted coronavirus disease 2019 (COVID-19) patients had lymphopenia, increasing to 85% in patients with severe disease (Huang et al., 2020). It has been reported that several genes representing the p53-mediated apoptosis signaling pathway are upregulated in peripheral blood mononuclear cells (PBMCs) of COVID-19 patients (Xiong et al., 2020). Moreover, SARS-CoV-2 RNA is detected in most immune cells, including T and B lymphocytes and NK cells (Ren et al., 2021). Therefore, unraveling the mechanism of lymphopenia in COVID-19 patients depends on whether SARS-CoV-2 directly infects immune cells to induce cell death.
Previously, some researchers found SARS-CoV-2 protein and virus-like particles in CD4+ T lymphocytes, but no replication-competent viruses were produced in vitro (Banerjee et al., 2020). Some groups found the SARS-CoV-2 protein in monocytes but not in T, B, or NK cells (Zheng et al., 2021). Still, other investigators verified that SARS-CoV-2 could robustly infect activated T cells (Shen et al., 2022). Thus, this issue is still controversial.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants have caused >500 million confirmed cases and >6 million deaths. Apart from the common clinical manifestations, 63% of admitted coronavirus disease 2019 (COVID-19) patients had lymphopenia, increasing to 85% in patients with severe disease (Huang et al., 2020). It has been reported that several genes representing the p53-mediated apoptosis signaling pathway are upregulated in peripheral blood mononuclear cells (PBMCs) of COVID-19 patients (Xiong et al., 2020). Moreover, SARS-CoV-2 RNA is detected in most immune cells, including T and B lymphocytes and NK cells (Ren et al., 2021). Therefore, unraveling the mechanism of lymphopenia in COVID-19 patients depends on whether SARS-CoV-2 directly infects immune cells to induce cell death.
Previously, some researchers found SARS-CoV-2 protein and virus-like particles in CD4+ T lymphocytes, but no replication-competent viruses were produced in vitro (Banerjee et al., 2020). Some groups found the SARS-CoV-2 protein in monocytes but not in T, B, or NK cells (Zheng et al., 2021). Still, other investigators verified that SARS-CoV-2 could robustly infect activated T cells (Shen et al., 2022). Thus, this issue is still controversial.