ABSTRACT
Human RNase A (human RNase A) superfamily contains 13 members (RNase 1~RNase 13) with different biological activities. In addition to the conserved catalytic sequence, its protein structure also has a significant diversity of sequences, which determines that human ribonuclease A can exert biological functions other than ribonuclease activity. Human RNase A superfamily members are expressed in various immune cells such as eosinophils, neutrophils, monocytes, and macrophages and can be secreted to exert various biological functions, including anti-microbial activity, promote host defense, participate in angiogenesis and sperm maturation, etc. Some members of the human ribonuclease A superfamily can exert antimicrobial and antiparasitic activities through direct actions such as hydrolysis of viral RNA, inhibition of viral replication, destruction of bacterial cell walls, promotion of microbial aggregation, damage to parasitic cell membranes and mitochondrial membranes, and indirect actions mediated by host innate immune cells, thereby participating in host defense. This article reviews the antimicrobial (including viruses, bacteria, and fungi) and antiparasitic activities of human ribonuclease A and their mechanisms of action. It also prospects the prospects of human ribonuclease A as an active antimicrobial substance and innate immune molecule for the treatment of severe and drug-resistant microbial infections.