Macrophage chemotactic factor is -
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.
High molecular weight
Chymotrypsin sensitive
Heat labile
Are antigenically similar to C3