Abstract: An improved composition containing peptides and nucleic acids has active components, i.e., which heighten the phagocytic activity f neutrophils, consisting of molecules with a molecular weight of at least 8 kDa, and preferably at least 15 kDa. The active components comprise peptides without aromatic portions and will absorb light at an absorption band of .DELTA..lambda.=200-235 mn, .lambda..sub.max =205 nm, in the UV spectrum. The composition is nontoxic and is formulated using casein, blood albumin, beef peptone, nucleic acid (RNA) and a base such as sodium hydroxide. The composition stimulates phagocytic activity of neutrophils if used at sufficient concentrations. A separate composition is obtained using the same components of manufacture, but filtering or centrifuging the composition to a molecular weight of <8-15 kDa which inhibits phagocytic activity of neutrophils for application in treating auto immune diseases.