CD40LG and COVID-19: After the detection of IgM and IgG to SARS‐CoV‐2 becoming “golden standard” for the diagnosis of suspected COVID‐19 patients, The National Medical Products Administration of China approved urgently five antibody kits based on different principle of detection, some of them are used to test total antibody to SARS‐CoV‐2, the others to detect of IgM and IgG, seperatedly.