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))))))