746 



SPERM, OVA, AND PREGNANCY 



In one series of experiments, 7 precipitin 

 bands were observed with washed human 

 sperm tested against rabbit antihuman 

 sperm sermii (Rao and Sadri, 1959). This 

 investigation further indicated that 4 of the 

 sperm antigens were common to seminal 

 plasma, but were not present merely as 

 contaminants. A parallel investigation, em- 

 ploying essentially identical procedures, led 

 to the conclusion that all of the human 

 sperm antigens are also present in plasma 

 and the two materials cannot, immunologi- 

 cally, be distinguished (Weil, Kotsevalov 

 and Wilson, 1956). A similar conclusion 

 grew out of a study of rabbit semen, and 

 the suggestion was made that "the effec- 

 tive antigens found in seminal plasma and 

 spermatozoa of semen appear to originate 

 in the seminal vesicle" (Weil and Finkler, 

 1958). Because practically all large molecu- 

 lar moieties and cells are potentially anti- 

 genic, and because spermatozoa may safely 

 be assumed to arise in the testis, this state- 

 ment obviously oversimplifies the facts. 

 The point is brought up merely to emphasize 

 the caution that should be exercised in the 

 use of and interpretations derived from vari- 

 ous techniques. There are sperm antigenic 

 differences in strains of animals and in in- 

 dividuals within strains, as Snell ( 1944 ) 

 and Landsteiner and Levine (1926) have 

 long since pointed out. More, rather than 

 less, immunologic differentiation will proba- 

 bly be forthcoming in the future. Indeed, 

 Weil (1960) has recently found that the 

 antigenic properties differ in epididymal and 

 seminal sperm of the rabbit; the sperma- 

 tozoa apparently take up and bind antigenic 

 material from the seminal plasma during 

 ejaculation. 



B. SPERM-INDUCED IMMUNE RESPONSES 

 IN THE MALE 



Antibodies against spermatozoa, both 

 foreign and those of the same individual, are 

 produced with facility by members of both 

 sexes. Why an animal should so react 

 against autologous antigen, i.e., a male 

 against its own sperm, is not clear. Ac- 

 cording to the concepts put forward by 

 Burnet and Tenner (1949), Billingham, 

 Brent and Medawar (1955, 1956), and 

 others, an organism undergoes a state of 



"recognition" of its own native substances 

 during the tolerant period before antibodies 

 are produced. Thereafter, it does not con- 

 sider these, or other substances initially 

 introduced during the tolerant period, as 

 foreign. The formation by an adult animal 

 of antibodies against injected autologous 

 spermatozoa, moreover, is generally attrib- 

 uted to the fact that sperm are not normally 

 produced until late in development; thus 

 they have not had a chance to be "recog- 

 nized" as native and are treated as foreign 

 material when injected. The further sup- 

 position must be made that spermatozoa in 

 the testis are somehow normally insulated 

 from the rest of the body, at least from the 

 antibody-forming sites, and therefore fail 

 to evoke antibody production and an im- 

 mune response. Such speculations are tenta- 

 tive and must await further understanding 

 of the general nature of antigenic stimula- 

 tion, antibody production, and antigen-an- 

 tibody complex formation, subjects which 

 are currently undergoing rapid growth and 

 ]icrplexing change (Talmage, 1957, 1959; 

 Lederberg, 1959). 



Because antibody production is evoked 

 by autologous sj^erm, the question arises 

 whether auto-immunization occurs and, fur- 

 ther, whether it is of any biologic signifi- 

 cance. Sperm agglutination occurs in other- 

 wise normal ejaculates of rabbit, bull, and 

 man, and the seminal plasma can be shown 

 to contain agglutinating antibodies (Wilson, 

 1954; see Tyler and Bishop, 1961). The pos- 

 sibility exists that an antigenic stimulus 

 for antibody formation may arise following 

 sperm absorption or penetration into the 

 epididymal mucosa during a period of in- 

 flammation, a process often associated with 

 intense leukocytic infiltration (Mason and 

 Shaver, 1952; Montagna, 1955; King, 1955). 

 In man, such a reaction is claimed to be 

 common after mild epididymal infection; 

 it causes no impairment of testicular func- 

 tion, but produces a tissue response char- 

 acterized by granulomatous lesions (Stein- 

 berg and Straus, 1946; Cronqvist, 1949; 

 King, 1955). Similar lesions have been de- 

 scribed in cases of granulomatous orchitis, in 

 which spermatozoa were present in macro- 

 phage cells and in the lymphatic system 

 (Friedman and Garske, 1949). Cruickshank 



