title: Diversity of antisperm antibodies bound to sperm surface in male immunological infertility.
abstract: OBJECTIVE
  The presence of antisperm antibodies (ASA) in males can reduce fecundity, however, relationship between the two is disputed. This study was performed to investigate if there is diversity of ASA bound to sperm surface using immunobead test (IBT) combined with complement dependent sperm immobilization test (SIT).
  
  
  METHODS
  The ASA bound to sperm surface were detected using the direct IBT (D-IBT) in 275 semen samples. In some cases with ASA detected by D-IBT, sperm immobilizing antibodies bound to sperm surface were also evaluated using direct SIT (D-SIT).
  
  
  RESULTS
  The incidence of the immunoglobulin G (IgG), IgA, and IgM classes of ASA detected by D-IBT were 2.5, 1.8, and 0.4%, respectively. Totally, nine (3.3%) infertile men had ASA on the sperm surface. D-SIT was tested positive in four (66.7%) of six cases with ASA assessed by D-IBT.
  
  
  CONCLUSIONS
  Some of the sperm-bound antibodies are associated with complement dependent sperm immobilizing antibodies, indicating that there exists a heterogeneity of sperm-bound antibodies. This result might be one of the reasons for the controversy about the relationship between ASA and immunological infertility in men.
authors.affiliation: Department of Obstetrics and Gynecology, Jichi Medical School, Tochigi, Japan. sibahara@jichi.ac.jp
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Shibahara
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Tsunoda
authors.forename: Akiyo
authors.initials: A
authors.lastname: Taneichi
authors.forename: Yuki
authors.initials: Y
authors.lastname: Hirano
authors.forename: Akiko
authors.initials: A
authors.lastname: Ohno
authors.forename: Satoru
authors.initials: S
authors.lastname: Takamizawa
authors.forename: Chieko
authors.initials: C
authors.lastname: Yamaguchi
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Tsunoda
authors.forename: Ikuo
authors.initials: I
authors.lastname: Sato
mesh_terms: D000906:Antibodies / Q000032:analysis*; D006801:Humans; D007248:Infertility, Male / Q000276:immunology*; D008297:Male; D013094:Spermatozoa / Q000276:immunology*
chemical_list: D000906:Antibodies