The function of MBL2 (mannose binding lectin 2, ENSG00000165471) is as follows. Calcium-dependent lectin, which acts as a pattern recognition receptor that initiates the lectin pathway of the complement system, a cascade of proteins that leads to phagocytosis and breakdown of pathogens and signaling that strengthens the adaptive immune system (PubMed:14515269, PubMed:22966085, PubMed:7634089, PubMed:9087411). Specifically recognizes and binds the mannose moiety of carbohydrates on the pathogen surface, activating the MASP1 serine protease and initiating the proteolytic cascade of the lectin complement pathway (PubMed:22966085, PubMed:2573758, PubMed:6643429, PubMed:8082295, PubMed:9087411). Upon SARS coronavirus-2/SARS-CoV-2 infection, activates the complement lectin pathway which leads to the inhibition SARS-CoV-2 infection and a reduction of the induced inflammatory response (PubMed:35102342). May bind DNA (PubMed:15145932). {ECO:0000269|PubMed:14515269, ECO:0000269|PubMed:15145932, ECO:0000269|PubMed:22966085, ECO:0000269|PubMed:2573758, ECO:0000269|PubMed:35102342, ECO:0000269|PubMed:6643429, ECO:0000269|PubMed:7634089, ECO:0000269|PubMed:8082295, ECO:0000269|PubMed:9087411}.