Microchimerism
Microchimerism (also microchimerism , Eng. Microchimerism ) referred to in the medicine , the previously little explored, possibly relatively common survival of other cells in the body. There are both cells of the fetus in the mother's body (fetal microchimerism) detected many years after the birth alive and vice versa maternal cells in the body of the child (maternal Microchimerism), in contrast to the previous view that the placenta prevents any cell exchange.
As early as the 1960s, researchers found evidence that blood and skin cancer cells from mothers can pass to the fetus. Signs of the transition of cells from the fetus to the mother found as early as 1890 the German pathologist Georg Schmorl in to toxemia , or preeclampsia deceased women. However, it was not until 1979 when the researcher Leonard A. Herzenberg found male blood cells (with the Y chromosome) in the blood of women pregnant with boys that this was also demonstrated in healthy women. In the 1990s and in more recent research, foreign cells were also detected in adults and in mothers years after pregnancy. Male DNA fragments in women's bodies (e.g. in the brain tissue) are most likely the result of previous sexual intercourse. Other hypotheses (twin pregnancies with male twins; undetected abortions) explain neither the high rate of microchimerism occurrence in women (over 60%) nor the large number of different DNA fragments per woman.
Whether this phenomenon is the cause of autoimmune diseases such as scleroderma or other diseases such as B. Juvenile dermatomyositis or neonatal lupus erythematosus is still unknown. The reasoning is obvious because women are affected by most autoimmune diseases much more often than men. Another application of the concept could be to use the cells in maternal blood for a safe prenatal diagnosis of child genetic defects.
The fetal cells are also called pregnancy associated progenitor cells PAPC and have some similarities with adult stem cells . A graft-versus-host reaction could not occur due to the HLA- II compatibility of the embryonic and maternal cells, so that the cells do not die. Abortion ( interruption ) may increase the likelihood of microchimerism.
Microchimerism also occurs in the context of organ transplants, in which a small number of blood cells are regularly transferred with the organ from the donor to the recipient. This type of microchimerism is said to have a positive effect on the tolerance of a foreign organ by the recipient's body.
literature
- DW Bianchi: Male fetal progenitor cells persist in maternal blood for as long as 27 years post partum . In: Proceedings of the National Academy of Sciences (PNAS) 93 (2), pp. 705-708 (1996)
- Hermann Feldmeier: Microchimerism - Foreign body cells between good and bad. Naturwissenschaftliche Rundschau 61 (10), pp. 507-509 (2008), ISSN 0028-1050
Web links
- Prenatal diagnosis and therapy - on the trail of microchimerism (PDF file; 173 kB)
- Spectrum: microchimerism
swell
- ^ Welt Online, January 18, 2004: Souvenir that makes you sick
- ↑ Deutsches Ärzteblatt, January 23, 2007: Microchimerism in the pancreas of diabetics - cause of disease or therapeutic approach? ( Memento of the original from February 11, 2007 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Spectrum of Science September 2008, pp. 54–61, "Foreign cells in us" by J. Lee Nelson
- ↑ Study: Women Store DNA From Every Man They've Ever Made Love With. In: Woked. Retrieved May 3, 2018, September 4, 2019 (American English).
- ↑ PC Evans et al .: Long-Term Fetal Microchimerism in Peripheral Blood Mononuclear Cell Subsets in Healthy Women and Women With Scleroderma. Blood 1999 (6), pages 2033–2037 full text (PDF)
- ↑ JL Nelson et al .: Microchimerism and HLA-compatible relationships of pregnancy in scleroderma. Lancet. 1998 (9102): 559-62. PMID 9492775
- ↑ O. Lapaire et al .: The non-invasive prenatal diagnosis from maternal blood. J Reproduktionsmed Endokrinol 2005 (5), pp. 272–277 full text (PDF; 425 kB)
- ↑ S. Maloney et al .: Microchimerism of maternal origin persists into adult life. J Clin Invest 1999 (104), 41-7. Full text
- ^ Message from the MHH Hanover, November 2, 1999: Why is a transplant rejected?
