PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 405760-10 1977 Incubation of human serum with either agarose or rat thymocytes resulted in the conversion of factor B, essential for complement activation via the alternative pathway, previously shown to provide the complement activity necessary for the cytotoxic reaction. Sepharose 38-45 distal membrane arm assembly component 2 like Rattus norvegicus 94-102