Patrícia Orlandini Gonçalez

Progesterone Decreases in vitro Indoleamine 2, 3-dioxygenase Expression in Dendritic and CD4+ Cells from Maternal-Fetal Interface of Rats

ABSTRACT Problem: Several mechanisms contribute to the tolerogenic state observed during pregnancy, such as the activity of the enzyme indoleamine 2, 3-dioxygenase (IDO). This initializes the catabolism of tryptophan, inducing T cells to apoptosis due to its deprivation and by the action of its catabolites in the placental microenvironment. Progesterone plays an important part on immunological tolerance mechanisms during pregnancy; however, there is no evidence it is related to IDO activity. Thus, this study aimed to investigate progesterone influence on the maternal-fetal interface of pregnant Wistar rats, by identifying IDO positive cells by immunophenotyping and flow cytometry under exogenous progesterone supplementation. Method of study: Placenta and embryo cells were cultured and separated into groups that received interferon γ or progesterone, supplemented or not with mifepristone. After 2 and 24 h, these were labeled with an anti-IDO and a series of antibodies specific to leucocytes and progesterone receptor and processed through flow cytometry analysis. Results: Progesterone induced a significant decrease in the expression of IDO in dendritic cells and CD4+ lymphocytes. Conclusion: The blocking of progesterone receptor on these cells by mifepristone restored IDO expression levels and may constitute evidence of the participation of this hormone through a direct route in these cells.

Ultrastructural characterization of bovine umbilical cord blood cells

The umbilical cord blood (UCB) is an important source of pluripotent stem cells, which motivated researches on ontogeny and transplantation. The morphological characterization of umbilical cord cells is the first step to establish subsequent experiments on these areas. Although some information on humans can be found, no data on UCB is available for bovines. Therefore, this work is the first attempt to conduct an ultrastructural characterization of bovine umbilical cord blood. Blood was collected from the umbilical cord of twenty fetuses by punction of the umbilical vein. Samples were processed for whole leucocytes observation by centrifugation and the buffy coat was collected. Cells were washed and pelleted and prepared according to the standard protocol of the transmission electron microscopy. The presence of cells with morphologic characteristics compatible with the precursors from the erythrocytic, neutrophilic, eosinophilic, basophilic, and lymphocytic lineages was observed. Atypical cells with peculiar morphological features, strongly similar to apoptotic cells, were seen. Bovine neutrophils with three types of cytoplasmic granules were also found in the blood. The ultrastructural characteristics of observed bovine UCB cells where similar to those found in other species, suggesting that bovines could possibly constitute an experimental model for approaches on UCB cells research.

Descrição anatômica da articulação metacarpo-falângica em ovinos

The joints anatomical description highlights the standards for biomechanical conditions that must be considered in the selection of a particular animal species. Thus, the objective was to describe the metacarpal phalangeal joint in sheep, for its architecture and adjacent structures. For this purpose, we used ten adult sheep, Santa Ines breed, males and females, randomly chosen. The anatomical specimens for the study were collected by the disarticulation of the distal row of carpal and metacarpal bone of an sheeps forelimb. To observe the joint capsule, adjacent structures were overruled and their topographical relationships with such joint analyzed. The longitudinal measures of the joint capsule and the III-IV metacarpal bones, proximal phalanges III and IV proximal phalanx were taken. Through the results, it is concluded that the metacarpal phalangeal joint in sheep presents similar topographical relationships described for other ruminants, with connections at the proximal and recesses at the distal areas.