ABSTRACT
Testicular germ cell tumours (TGCT) exhibit remarkable ability to differentiate into virtually all somatic tissue types. In this study, we investigated changes in mucin-type O-glycosylation, which have been associated with somatic cell differentiation and cancer. Expression profile of simple mucin-type O-glycans (Tn, sialyl-Tn, T), histo-blood group H and A variants and six polypeptide GalNAc-transferases (T1-4, T6, T11) that control the site and density of O-glycosylation were analysed by immunohistochemistry during human testis development and in TGCT. Normal testis showed a restricted pattern; gonocytes expressed abundant sialyl-Tn and sialyl-T, and adult spermatogonia were devoid of any glycans, whereas spermatocytes and spermatids expressed exclusively glycans Tn and T and the GalNAc-T3 isoform. A subset of mature ejaculated spermatozoa expressed an additional glycan sialyl-T. The pattern found in testicular neoplasms recapitulated the developmental order: Pre-invasive carcinoma in situ (CIS) cells and seminoma expressed fetal type sialylated glycans in keeping with their gonocyte-like phenotype. Neither simple mucin-type O-glycans nor GalNAc-transferase isoforms were found in undifferentiated nonseminoma, i.e. embryonal carcinoma, whereas teratomas expressed them all to some extent but in a disorganized manner. We concluded that simple mucin-type O-glycans and their transferases are developmentally regulated in the human testis, with profound changes associated with neoplasia. The restricted O-glycosylation pattern in haploid germ cells suggests a role in their maturation or egg recognition/fertilization warranting further studies in male infertility, whereas the findings in TGCT provide new diagnostic tools and support our hypothesis that testicular cancer is a developmental disease of germ cell differentiation.
Subject(s)
Antigens, Tumor-Associated, Carbohydrate/metabolism , Antigens, Viral, Tumor/metabolism , Cell Transformation, Neoplastic/metabolism , N-Acetylgalactosaminyltransferases/metabolism , Testicular Neoplasms/metabolism , Testis/metabolism , Antigens, Tumor-Associated, Carbohydrate/genetics , Antigens, Viral, Tumor/genetics , Cell Differentiation/physiology , Cell Transformation, Neoplastic/pathology , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Humans , Male , N-Acetylgalactosaminyltransferases/genetics , Phenotype , Spermatogenesis/physiology , Spermatozoa/pathology , Testicular Neoplasms/pathology , Testis/pathology , Polypeptide N-acetylgalactosaminyltransferaseABSTRACT
OBJECTIVE: To investigate the influence of sera and peritoneal fluids (PFs) from fertile and infertile women on the binding of antisperm antibodies to the surface of spermatozoa. DESIGN: The immunoglobulin (Ig) G antisperm antibodies binding to the surface of liver spermatozoa was evaluated after their incubation in antisperm antibodies-positive serum from an infertile male in the presence and absence of female sera or PFs. SETTING: Russian Scientific Center for Obstetrics, Gynaecology, and Perinatology. PATIENT(S): Serum and PF samples from fertile and infertile women; antisperm antibodies-positive serum from infertile men; high-quality fresh semen from healthy donors. INTERVENTION(S): Serum samples were obtained from fertile and infertile women and from infertile men. Peritoneal fluids were collected during routine laparoscopy. MAIN OUTCOME MEASURE(S): The proportion of spermatozoa positive for IgG antibodies and the quantity of antisperm antibodies on the sperm surface measured by flow cytometry (FCM). RESULT(S): The addition of sera from fertile or infertile women with endometriosis or pelvic adhesion disease to an IgG antisperm antibodies-positive male serum resulted in significant inhibition of the antisperm antibodies binding to the sperm surface. CONCLUSION(S): Sera of fertile as well as infertile woman contain factors that block IgG antisperm antibodies binding to the surface of live spermatozoa.
