Product Description

Natural human C4a is prepared by cleavage of human C4 protein by human C1s. It is produced during activation of both the classical and lectin pathways of complement.C4a is a member of the anaphylatoxin family of three proteins (C3a, C4a and C5a) produced by the activation of complement (Hugli, T.E. et al. (1981)).It is an unglycosylated polypeptide containing 77 amino acids with a molecular mass of 8,759 daltons.Many of the biological functions of C4a are similar to those of C3a, but the specific activities are far below those of C3a.C4a activity is so low, in fact, that it was initially thought to be inactive.These measured activities include inducing muscle contraction in the guinea pig ileum test (spasmogenic activity), desensitization of muscle to C3a stimulation suggesting that the same receptor for both C3a and C4a is involved (tachyphylactic activity) and inducing vascular permeability in human skin (Gorski J.P. et al. (1979)).C4a does not show tachyphylactic activity against C5a or chemotactic activity.Removal of the C-terminal arginine by serum carboxypeptidase N destroys all these activities (Meuller-Ortiz, S.L., et al. (2009)).C4a appears to act through the C3a receptor (C3aR) which is a G-protein coupled receptor found widely distributed on peripheral tissues, lymphoid cells (neutrohphils, monocyes, and eosinophils) and in the central nervous system (astrocytes, neurons and glial cells) (Law, S.K.A. and Reid, K.B.M. (1995)).

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Complement Technology，Inc。（CompTech）致力于为生物医学研究界提供最高质量的补充试剂。CompTech的业主和员工在补充领域拥有超过80年的综合经验。我们是我们销售的补充试剂的原始制造商，我们努力成为最优质试剂的最低成本供应商。我们不断扩大我们生产的试剂系列，以满足不断变化的研究需求。我们欢迎您提供所需新试剂的建议。