title: The classical complement pathway: activation and regulation of the first complement component.
mesh_terms: D000595:Amino Acid Sequence; D003166:Complement Activating Enzymes / Q000266:history / Q000276:immunology*; D003167:Complement Activation; D003172:Complement C1 / Q000266:history / Q000276:immunology*; D003174:Complement C1 Inactivator Proteins / Q000266:history / Q000276:immunology*; D003171:Complement Pathway, Classical; D006801:Humans; D046911:Macromolecular Substances; D008970:Molecular Weight; D011487:Protein Conformation; D011951:Receptors, Complement / Q000276:immunology*
chemical_list: D003172:Complement C1; D003174:Complement C1 Inactivator Proteins; D046911:Macromolecular Substances; D011951:Receptors, Complement; D003166:Complement Activating Enzymes