Assessment of thyroglobulin expression in reproductive organs at different stages of mouse estrous cycle

Prevalence of abortion is higher in women with autoimmune thyroid disease. In the majority of cases, however, no abnormality of thyroid function is detected despite the high levels of antithyroid antibodies. The direct influence of such harmful autoantibodies in female reproductive organs may serve a role in pregnancy loss. In this study, expression of thyroglobulin in the reproductive tissues of cycling mice has been evaluated. Stages of estrous cycle were determined by cellular morphology and ratio of epithelial cells to leukocytes in vaginal smear of Balb/C mice. At each phase, the mice were sacrificed and their uterus, ovary and fallopian tubes were removed. Expression of thyroglobulin-specific transcript in endometrium was investigated by two sets of primers using reverse transcriptase-polymerase chain reaction [RT-PCR]. In addition, expression of thyroglobulin in reproductive tissues was assessed by immunohistochemistry and dot blot analysis. The results showed that thyroglobulin mRNA is not expressed in endometrial tissue of Balb/C mice at any stage of estrous cycle. Immunohistochemical analysis also confirmed that thyroglobulin or its cross reactive-antigens are not expressed at the protein level in the female reproductive organs. The results showed that thyroglobulin was not expressed in the reproductive organs of female mice. It is plausible that antithyroglobulin antibodies could interact with newly-generated antigens during placentation and pregnancy

Indoleamine 2,3-dioxygenase [IDO] is expressed at feto-placental unit throughout mouse gestation: An immunohistochemical study

The cells expressing Indoleamine 2, 3-dioxygenase [IDO] in feto-maternal interface mediate tryptophan catabolism, hence protect allogeneic fetus from lethal rejection by maternal immune responses. In this study, we report immuno-localization of IDO cells in murine reproductive tract and placenta throughout mouse pregnancy by immunohistochemistry. Syngeneic pregnant mice were examined for vaginal plug to discover about their state of pregnancy. A total of three pregnant mice were examined at each stage. The examination was further confirmed by the detection of sperm in vaginal smear. On the gestational days of 2[nd], 12[th] and 18[th], the uterus and oviduct were removed and expression of IDO was investigated in the endometrium, placenta and oviduct by immunohistochemistry. Our results showed that IDO is expressed consistently in feto-maternal interface throughout pregnancy. In endometrium, expression of IDO was predomin-antly confined to luminal and glandular epithelial cells. Cells at junctional and labyrinth zones of placenta showed strong IDO immunoreactivity as well. Expression of IDO at the protein level in reproductive tract of pregnant mice during entire periods of gestation points to its potential protective role in maintenance of pregnancy. In our knowledge this is the first report of expression of IDO in feto-maternal phase during murine pregnancy