B2M and COVID-19: Moreover, the abnormal expression of hub genes (SRC, RHOA, CD40LG, CSF1, TNFRSF1A, FCER1G, ICAM1, LAT, LCN2, PLAU, CXCL10, CD40, IRF7, and B2M) was regarded as the main cause of cytokine storm syndrome in COVID-19 patients.