Have you ever heard of microchimerism? It is the harboring of small numbers of cells that originated in a genetically different individual. This happens naturally during pregnancies, when the cells of the mother are transported to the fetus and vice versa. Such cells can be found in different regions of body. Currently it is still not clear, whether they are harmful or helpful for the women’s organism.
The broadest research in microchimerism(MC) is dedicated to finding a link between autoimmune diseases and MC. So far, there are 200 papers published on MC-autoimmune disease coincidence. Nearly half of them, as seen on the figure below, are from USA. Studies suggests that the number of male cell DNA in women with autoimmune diseases such as rheumatoid arthritis, scleroderma, thyroiditis, etc., are higher than in women without these conditions. The most cited research paper on relationship between MC and autoimmune disease is “Microchimerism and HLA-compatible relationships of pregnancy in scleroderma.” with 55 citations.
Researchers also try to find a connection between MC and cancer. When we look at the figure below, we can see that the number of publications for this topic is nearly four times lower than the number of publications on autoimmune diseases. However, we can see that the research goes forward a little bit every year. The most interesting and cited publications on cancer-MC incidence are: “Cervical cancer and microchimerism.” and “Fetal microchimerism in women with breast cancer.” Interestingly, the first one brought the evidence, that: “Cervical cancer might be associated with microchimerism, possibly from fetomaternal cell trafficking.” and gathered data in second one conclude that: “The allogeneic fetal-microchimerism may contribute to reduction in risk of breast cancer. ” The fact, that the cells from the fetus can either help or harm the body of the mother, even after ten or twenty years after the pregnancy, is rather shocking.
Based on the global literature available, we can conclude that the MC has different effects on different parts of the body. What about the brain and CNS? How many research papers were published on this topic? There are only few publications about this topic, but when we look at their results, we can see that the male cells in female brain helps to “repair” the brain cells. One of the most interesting papers about effects of MC on brain is “Male microchimerism in the human female brain.” which explores the relations between MC and Alzheimer’s disease.
We think that MC is an interesting subject of research and it should be explored more broadly. Further research in MC can help to better understand the interactions of fetus and woman during the pregnancy and maybe even predict and prevent the onset of some diseases.