ISSN:
1432-1203
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary Male-specific H-Y antigen may be defined by graft rejection, killer cell action or antibodies. Most commonly H-Y antigen is detected in assays using H-Y antisera. In these tests errors may arise from various causes: 1) Auto- and heteroantibodies cross-reacting with target cells. 2) Restriction phenomena. 3) MHC-dependent modification of the amount of H-Y antigen present on different tissues. 4) Modification of cell surface antigens by bacteria or viruses. Regarding the third definition of H-Y antigen, four different “states” can be distinguished in the mammalian male. H-Y occurs (1) as an integral part of the plasma membrane; (2) unspecifically attached to the membrane of human erythrocytes; (3) free in solution; (4) bound to its gonad-specific receptor. Redistribution experiments suggest that H-Y and β 2-m are associated on the cell membrane. Coredistribution is not found of H-Y and MHC antigens. An antibody blocking technique demonstrates association of H-Y and H-2D antigens on unfixed lymphoid, but not on testicular cells. Human erythrocytes lacking β 2-m do not integrate H-Y antigen into the cell membrane. Male erythrocytes, however, absorb H-Y antigen from the serum. The origin of H-Y antigen in the serum is not clear. It may be shed from cell membranes, derive from the testis which actively secretes H-Y antigen, or both. H-Y antigen is bound by a gonad-specific receptor. This receptor is present in the gonads of both sexes. H-Y antigen is supposed to mediate testis differentiation via this receptor. Reaggregation experiments in vitro using dissociated gonads of the newborn rat demonstrate that ovarian cells reorganize into testicular structures in the presence of H-Y antigen. The assumption cannot be confirmed that addition of H-Y antiserum to testicular cells results in ovarian structures. This finding, however, does not conflict with the view that H-Y antigen is involved in testis differentiation, e.g. by inducing testis cell-specific functions via the gonad-specific receptor.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00284145
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