Interestingly, among the nine clusters, the critical COVID-19 dominant cluster 1 showed the lowest count and weight of both outgoing and incoming signaling, while cluster 2 (healthy dominant) was among the highest ranking in both (Fig. 5A), indicating that the CD1C-CD141-DCs in critical COVID-19 were communication defective and were completely different to those of the healthy controls. The gene discussed is CD1C; the disease is COVID-19.