ABSTRACT
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
ABSTRACT
SUMMARY: The morphology of the interstitial tissue of sexually active and resting testis of the guinea fowl were studied. Six adult health birds of active and resting phases of reproductive cycle were used for this study. The interstitial tissue consisted of loose connective tissue, interstitial cells (Leydig cells), few connective cells, blood vessels and adrenergic nerve fibres in the present study in both active and resting testes. The interstitial tissue was compact in sexually active testis whereas, the volume of the tissue was found to be increased in resting testis. The loose connective tissue of the interstitial tissue composed of mainly of collagen fibres and few reticular fibres whereas elastic fibres were absent in both groups studied. The interstitial cells appeared in clusters of a few cells and were relatively less in the active testis than the resting testis. The interstitial cells were pale staining or polygonal cells with euchromatic nuclei with few large lipid droplets in the active testis whereas the cells were flat and highly heterochromatic with numerous small lipid droplets in resting testis. Few macrophages were found only in resting testis. Interstitial cells showed negative reaction to alkaline, acid phosphatases and PAS in both groups studied but positive for lipids. The interstitial tissue was well vascularised with centrally located blood vessels in the active testis whereas the blood vessels were small and inconspicuous in the resting testis. The lymphatic vessels were not identified in both groups studied.
RESUMEN: Se estudió la morfología del tejido conectivo intersticial en testículos sexualmente activos y en reposo de la gallina de Guinea (Numida meleagris). Se utilizaron seis gallinas de Guinea machos adultos sanos, en fase activa y de reposo del ciclo reproductivo. El tejido conectivo intersticial estaba formado por tejido conectivo laxo, células endocrinas intersticiales, pocas células conectivas, vasos sanguíneos y fibras nerviosas adrenérgicas, tanto en testículos activos como en reposo. El espacio intertubular en los testículos sexualmente activos era menor en comparación a los del testículos en reposo. El tejido conectivo laxo estaba compuesto principalmente de fibras colágenas y en menor cantidad de fibras reticulares. Las fibras elásticas estaban ausentes en ambos grupos. Las células endocrinas intersticiales se organizaban en racimos de pocas células y se observaban con menor frecuencia en los testículos sexualmente activos. Las células endocrinas intersticiales de los testículos activos presentaban forma poligonal, citoplasma levemente eosinofílico con algunas gotas lipídicas de gran tamaño en su interior y nucleos redondos con cromatina laxa. Las células intersticiales de los testículos en reposo eran planas y altamente heterocromáticas, con numerosas gotas lipídicas pequeñas en su citoplasma. Las células intersticiales mostraron una reacción negativa a las fosfatasas ácidas, alcalinas y PAS en ambos grupos, Sin embargo presentaron reacción positivas para los lípidos. El tejido conectivo intersticial estaba bien vascularizado con vasos sanguíneos situados centralmente en el testículo activo y vasos sanguíneos pequeños y discretos en el testículo en reposo. Los vasos linfáticos no fueron identificados en los dos grupos estudiados.Los macrófagos fueron observados solo en los testículos en reposo, aunque en escasa cantidad.