decot@cwruecmp.UUCP (Dave Decot) (01/25/84)
The following is not a professional immunologist's description of the current theory, but it is MY current theory. Please poke holes if you feel qualified. From the study in the JAMA article, there is reason to believe that sperm can trigger an immune response in the recipient when injected by anal intercourse. Through my limited exposure to reproductive biology (no giggling in the third row!), I seem to remember that, under regulation heterosexual intercourse, the woman's immune system is prevented from reacting to the invasion of the foreign sperm. This could be effected by a) a change in the woman's immune system during intercourse caused by i) hormonal reaction to psychological stress ii) some reaction to sperm chemistry, possibly accelerated antibody-antigen immunity? b) a characteristic of sperm (haploidy? chemistry?) that renders its genetic information "acceptable" to the female system. I believe that a combination of these mechanisms is responsible for the lack of immune activity. In any case, a vestigal "female system" of immunity to sperm may remain in men. Such an intended temporary suspension of immune activity may malfunction when the injection is through another site, i.e. the colon, particularly in men, and possibly in women. Another possibility is that the immune and hormonal changes that occur in response to fertilization may also have vestigal analogues in men, although I don't know what a male system would misconstrue as a "fertilization." The normal changes in women occur so that the zygote will not be rejected. Am I crazy or what? Dave Decot decvax!cwruecmp!decot (Decot.Case@rand-relay)