Immunocytochemical detection of thymocyte antigenic determinants in developing lymphoid organs of sea bassDicentrarchus labrax(L.)

Water Oxygen Content Affects Distribution of T and B Lymphocytes in Lymphoid Tissues of Farmed Sea Bass (Dicentrarchus Labrax)

“…It was observed a relevant increment of density in hyperoxygenated fish compared with the NO group. Similar observations occurred previously in normal oxygenated sea bass by immune-histochemistry and flow cytometry [18,26,27]. Taking together the data of distribution of lymphocytes evidenced that hyperoxia treatment (oxygenation of 13 mg/L) induces selective increments of T-and B-cells among hematopoietic tissues.…”

“…In leukocytes isolated from the head kidney and the spleen of fish, the receptor numbers for cortisol increase in number following chronic stress or in vivo cortisol treatment [29][30][31] and the redistribution of leukocytes, caused by the cortisol treatment, was suggested to have contributed to this effect. Estrogens affect different stages of B-cell development and modify the humoral response [27], while estrogen modulators have been found to regulate B development and function [28]. Conversely, effects of glucocorticoids in the immune system of fish include the reduction of antibody titers [29] and leukocyte redistribution [30].…”

Fish thymocyte viability, apoptosis and necrosis: in-vitro effects of organochlorine contaminants

“…Lai et al (1994) suggest that exogenous chemical-induced alterations in thymic haematopoietic cells are sensitive indicators of exposure to immunomodulators. During teleost development the fish thymus is the first lymphoid organ to contain lymphocytes and plays a central role in immunoregulation (Abelli et al, 1996). Further, having no specialised thymic membrane capsule, the fish thymus is relatively unprotected from some waterborne xenobiotics (Tatner & Manning, 1985).…”

Apoptosis of thymocytes in developing sea bassDicentrarchus labrax(L.)

“…*Author to whom correspondence should be addressed: Dr Luigi Abelli, Dipartimento di Scienze Ambientali, Università della Tuscia, Via S. Camillo de Lellis, blocco D, 01100 Viterbo, Italy. E-mail: labelli@unitus.it The chronology of thymic development in the sea bass Dicentrarchus labrax (L.) has been previously defined by histology (Abelli et al, 1994) and immunohistochemistry with the monoclonal antibody (MAb) DLT15 that recognises antigenic determinants expressed by thymocytes and T cells (Scapigliati et al, 1995;Abelli et al, 1996). In situ end-labelling of fragmented DNA was employed in the present study to analyse the onset and rate of negative selection of developing lymphocytes in the thymus of the sea bass.…”