HLA-G in murine peripheral blood after interruption of pregnancy

HLA-G antigens are highly expressed in maternal peripheral blood during early pregnancy in transgenic mice. In this study, we determined the levels of HLA-G in white blood cells during early pregnancy and after interruption of pregnancy in triple transgenic mice (H-2K(b)/HLA-G, h beta 2m, and hCD2/hCD8-TRI). The pregnancies were interrupted on day 7 using the anti-progesterone agent millepristone (RU486). Blood samples of 20 pregnant TRI mice were taken and the HLA-G levels were determined on days 2, 4 and 6 of pregnancy and on days 9, 11 and 13 after fertilization. The monoclonal antibody W6.32, specific for monomorphic determinant HLA class I molecules, was used in combination with an immunolocalization method Using it photonic microscope, The HLA-G levels increased gradually on days 2, 4. and 6 of pregnancy, and the interruption of pregnancy on day 7 was followed by it decrease of FILA-G levels. The data indicate that pregnancy is characterized by the early), presence of HLA-G in maternal peripheral blood in TRI transgenic mice and suggest that HLA-G may serve as it useful indicator for pregnancy maintenance and well-being. (c) 2005 International Federation for Cell Biology. Published by Elsevier Ltd. All rights reserved.