A biologic factor whose activities affect or play a role in the functioning of the immune system
(=> (Immunologic-Factor ?Self) (And (Exists (?A) (And (Affects ?Self ?A) (Immune-System ?A))) (Exists (?B) (And (Indicates ?Self ?B) (Or (Virus ?B) (Rickettsia-Or-Chlamydia ?B) (Pathologic-Function ?B) (Bacterium ?B))))))