Measurement of rhesus monkey (Macaca mulatta) apolipoprotein B in serum by radioimmunoassay: comparison of immunoreactivities of rhesus and human low density lipoproteins

A sensitive and specific double antibody radioimmunoassay for the major apolipoprotein (apoB) of rhesus (Macaca mulatta) serum very low density lipoprotein (VLDL) and low density lipoprotein (LDL) is described. The antiserum was raised to LDL (d 1.030 to 1.040 g/ml) and the LDL2 (d 1.020 to 1.050 g/ml) was labeled with 125I by the chloramine-T or iodine monochloride method. The assay, which was sensitive to 0.02 to 0.5 μg of LDL2, had an interassay coefficient of variation of 4.5%. This assay was successfully used to measure apoB in the whole serum and low density lipoproteins of control monkeys maintained on a standard Purina monkey chow (PMC) diet and of three groups of monkeys fed atherogenic diets: an average American diet, a 25% peanut oil and 2% cholesterol-supplemented PMC diet, and a 25% coconut oil and 2% cholesterol-supplemented PMC diet