NID1 and COVID-19: We previously found that BM structure is an important microenvironment supporting the fate and functional polarity of EpSCs.[30] We observed that the proteins (type IV collagen, laminins, HSPG2, NID1, etc.)of BM structure and hemidesmosome complex (ITGA6) were severely damaged in the COVID‐19 skin tissues (Figure 4a).