Macrophage chemotactic factor is -: (A) High molecular weight, (B) Chymotrypsin sensitive, (C) Heat labile, (D) Are antigenically similar to C3
Answer is B. Ans is 'b' i.e.,Chymotrypsin sensitive (Ref Immunology p. 278)Macrophage chemotactic factor propeies has Low molecular weight (12000), has a isoelectric points of 10.1 & 5.6, and is sensitive to treatment by chymotrypsin while resistant to RNase and neuraminidase.It is heat stable and angenically different from C3 & C5.