TY - JOUR
T1 - Functional gap junctions in thymic epithelial cells are formed by connexin 43
AU - Alves, Luiz Anastacio
AU - de Carvalho, Antonio Carlos Campos
AU - Lima, Elizabeth Obino Cirne
AU - Souza, Claudio Marcos Rocha E.
AU - Dardenne, Mireille
AU - Spray, David Conover
AU - Savino, Wilson
PY - 1995/2
Y1 - 1995/2
N2 - A multiparametric study was carried out to investigate the presence and possible role of communicating junctions in the thymus, particularly in the thymic epithelium, the major component of the thymic microenvironment. The presence of direct cell‐cell communication mediated by gap junctions was demonstrated in human and murine thymic epithelial cells (TEC) by means of in situ and in vitro immunohistochemical labeling as well as in vitro fluorochrome injection and double whole‐cell patch clamp experiments. Moreover, both immuno‐ and Northern blot studies revealed that the gap junction protein connexin 43 and its mRNA were present in TEC. Importantly, we showed that thymic endocrine activity, as ascertained by thymulin production, could be specifically downmodulated in vitro by a gap junction inhibitor, octanol. We also investigated the existence of gap junctions between TEC and thymocytes. In thymic nurse cells we were able to detect cell‐cell communication, although only a minor percentage of epithelial/thymocyte pairs were coupled in a given moment. In contrast, intercellular communication was not detected between cultured phagocytic cells of the thymic reticulum and the respective rosetting thymocytes. We suggest that gap junctions formed by connexin 43 may represent a novel (and rather cell type‐specific) pathway for intrathymic cellular communication, including TEC/TEC as well as possible TEC/thymocyte interactions.
AB - A multiparametric study was carried out to investigate the presence and possible role of communicating junctions in the thymus, particularly in the thymic epithelium, the major component of the thymic microenvironment. The presence of direct cell‐cell communication mediated by gap junctions was demonstrated in human and murine thymic epithelial cells (TEC) by means of in situ and in vitro immunohistochemical labeling as well as in vitro fluorochrome injection and double whole‐cell patch clamp experiments. Moreover, both immuno‐ and Northern blot studies revealed that the gap junction protein connexin 43 and its mRNA were present in TEC. Importantly, we showed that thymic endocrine activity, as ascertained by thymulin production, could be specifically downmodulated in vitro by a gap junction inhibitor, octanol. We also investigated the existence of gap junctions between TEC and thymocytes. In thymic nurse cells we were able to detect cell‐cell communication, although only a minor percentage of epithelial/thymocyte pairs were coupled in a given moment. In contrast, intercellular communication was not detected between cultured phagocytic cells of the thymic reticulum and the respective rosetting thymocytes. We suggest that gap junctions formed by connexin 43 may represent a novel (and rather cell type‐specific) pathway for intrathymic cellular communication, including TEC/TEC as well as possible TEC/thymocyte interactions.
KW - Connexin 43
KW - Gap junction
KW - Thymic epithelium
KW - Thymocytes
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U2 - 10.1002/eji.1830250219
DO - 10.1002/eji.1830250219
M3 - Article
C2 - 7875205
AN - SCOPUS:0028905615
SN - 0014-2980
VL - 25
SP - 431
EP - 437
JO - European Journal of Immunology
JF - European Journal of Immunology
IS - 2
ER -