HUMAN AUTOANTIBODIES RECOGNIZING HUMAN AND MOUSE PREIMPLANTATION STAGES

PROBLEM: To find out whether autoantibodies against human preimplantat ion stages are present in some human sera and, if so, whether the anti bodies could be capable to affect the egg development and/or to trigge r an activation of the complement system at the procedures of assisted conception. METHODS: 1. Immunohistochemistry on blots of human preimp lantation stages. 2. Immunohistochemistry on paraffin sections of huma n and mouse preimplantation stages. 3. Culture of mouse morulae to ana lyze complement activation. RESULTS: 1. Some human sera contained auto antibodies against human preimplantation stages. 2. Human-mouse cross- reacting antibodies against preimplantation stages occurred. 3. Immune complexes, formed on mouse preimplantation stages, activated the comp lement systems in egg cultures, resulting in a damaging of the eggs. C ONCLUSION: The presence of natural autoantibodies to preimplantation s tages may be associated with reproduction failure, caused by a direct effect by the autoantibodies and/or an activation of the uterine compl ement system by the immune complexes formed.