[Current program of in-vitro fertilization at the Erasmus Hospital: initial results and original ethical aspects].

The clinical results including all in vitro fertilization (IVF) cycles with oocyte pick-up in 1990 are presented. Different types of treatment including classical IVF and embryo transfer, laparoscopic replacement of zygotes in the fallopian tube (ZIFT), IVF with donor sperm (IVF-D), cross fertilization test, embryo freezing, oocyte donation and IVF with epididymal sperm were performed. The total pregnancy rate obtained reaches 38% per oocyte pick-up, 30% of clinical pregnancies (including 4 pregnancies obtained with frozen and thawed embryos).

Increased expression of Ia antigens on B cells after neonatal induction of lymphoid chimerism in mice: role of interleukin 4.

BALB/c mice rendered chimeric at birth by injection of 10(8) (A/J X BALB/c)F1 spleen cells develop a lupus-like autoimmune disease linked to the activation of donor B cells by host T cells. As in vitro studies previously indicated that interleukin 4 (IL4) was a mediator of the interactions between T and B cells, we analyzed the intensity of Ia antigen expression on B cells of chimeric mice. Flow cytometric analysis with anti-Ia monoclonal antibodies (mAb) revealed that B cells from spleens and lymph nodes of 2-week-old chimeric BALB/c mice displayed a two- to threefold increase in membrane Ia antigen expression, this increase still being present in spleens of 30-week-old animals.

Autoimmunity and glomerulonephritis after neonatal induction of lymphoid chimerism in mice: role of donor B cells and host T cells.

Balb/c mice neonatally injected with semiallogeneic (A/J x Balb/c) F1 or (C57 BL/6 x Balb/c) F1 hybrid spleen cells develop autoantibodies, marked increase in serum levels of IgG1 and IgE, lymphoid hyperplasia, and immune-complex glomerulonephritis. F1 donor B cells play a dominant role in the pathogenesis of this autoimmune disease since B-cell chimerism is required for the occurrence of immunopathology, donor-specific allotype is expressed on serum anti-DNA antibodies, and substantial amounts of donor-derived immunoglobulins are present in the kidney eluate of chimeric mice. In vitro experiments indicate that T cells from diseased Balb/c mice induce activation of F1 donor B cells with secretion of anti-DNA antibodies.