Immunohistochemistry of Canine Hair Follicle Stem Cells (cHFSCs) by using CK15 and CK19

Adult body harbors powerful reservoir of stem cells that maintains homeostasis by tissue regeneration and in response to disease and injury. Hair follicle is a dynamic mini organ supporting important biological functions of the body in maintaining homeostasis and skin tissue self-renewal. This study was carried out with the objective of finding the adult stem cells in canine hair follicular tissue. To conduct this study, adult canine skin samples (n=12) irrespective of breed and sex were collected. To characterize the hair follicle stem cells, paraffin sections of canine hair follicles were immunostained with positive hair follicle stem cell markers like Anti- cytokeratin 15 (CK15) and Anti-cytokeratin 19 (CK19) and FITC conjugated and HRP conjugated secondary antibodies were used. Immunoreactivities for CK15 and CK19 were observed in the bulge/isthmus region of hair follicles in between the infundibulum and suprabulbar regions and occupied most part of the peripheral layer of outer root sheath cell. Immunophenotyping of canine Hair Follicle Stem Cells (cHFSCs) in the bulge region of hair follicle helps in confirmation of in vitro culture of cHFSCs from the bulge region which will be further used for translational research

Microarchitecture of the Palatine Tonsil in Sheep (Ovis aries) / Microarquitectura de la Tonsila Palatina en Oveja (Ovis aries)

The tissue pieces of palatine tonsil were collected from different postnatal age groups of sheep from the Corporation Slaughter House, Perambur, Chennai. The palatine tonsil consisted of a surface epithelium, capsule, tonsillar lobes, crypts, crypt epithelium and tonsillar follicles. The surface epithelium over the palatine tonsil was made up of non-keratinized stratified squamous epithelium in all the postnatal age groups studied. The palatine tonsil was clearly demarcated from the surrounding structures by a distinct connective tissue capsule and one septa dividing the tonsil into two lobes. The surface epithelium was invaginated into the substance of the tonsil to form primary and secondary crypts in each lobe. The crypt epithelium covered the regions of lymphoid follicles became lymphoepithelium. The macrophages were also observed in the epithelium. In the areas of lymphoepithelium the basement membrane was interrupted since lymphocytic infiltration was heavy into the epithelium. Numerous secondary tonsillar follicles with germinal centers separated by interfollicular areas were observed in the palatine tonsil. The tonsillar follicles consisted of a mantle zone, which was heavily populated with small darkly stained lymphocytes. These mantle zones were always oriented towards the crypts. The tonsillar follicles of young sheep showed many medium and small sized lymphocytes, lymphoblasts and also reticulocytes. The reticular cells usually appeared larger than lymphocytes and had a more abundant and organized cytoplasm with vacuoles.

Fueron recolectadas piezas de tejido desde la tonsila palatina de ovejas con diferentes edades postnatales, desde la Corporación Slaughter House, Perambur, Chennai. La tonsila palatina consistía en un epitelio de superficie, cápsula, lóbulos de las tonsilas, criptas, epitelio de las criptas tonsilares y folículos. El epitelio superficial sobre la tonsila palatina estaba compuesto, en todos los grupos estudiados, de epitelio escamoso estratificado no-queratinizado. La tonsila palatina se delimitó claramente de las estructuras circundantes por un tejido conectivo capsular y un septo dividiendo la tonsila en dos lóbulos. El epitelio superficial se invaginó dentro de de la tonsila para formar criptas primarias y secundarias en cada lóbulo. El epitelio de las criptas cubrió las regiones de folículos linfoides transfomándose en linfoepitelo. También se observaron macrófagos en el epitelio. En las áreas de linfoepitelo la membrana basal estaba interrumpida por la infiltración linfocitaria y fue mayor en el epitelio. Fueron observados numerosos folículos tonsilares secundarios con centros germinales separados por áreas interfoliculares. Los folículos tonsilares consistían en una zona del manto que estaba densamente poblada con pequeños linfocitos intensamente teñidos. Estas zonas del manto se orientaron siempre hacia las criptas. Los folículos tonsilares de las ovejas jóvenes mostraron muchos linfocitos de tamaño medianos y pequeños, linfoblastos y también reticulocitos. Las células reticulares usualmente aparecían más grandes que los linfocitos y tenían un citoplasma más abundante y organizado con vacuolas.