bafilomycin-a and Chronic-Disease

Previous reports have shown that thymic stromal lymphopoietin (TSLP) plays a role in atopic diseases. This study was undertaken to investigate the expression of TSLP in the giant papillae obtained from patients with vernal keratoconjunctivitis (VKC) or atopic keratoconjunctivitis (AKC), and its functional roles were analyzed.. TSLP mRNA expression was examined in resected conjunctival samples obtained from four patients with VKC/AKC and three control subjects by reverse transcription-polymerase chain reaction. Anti-TSLP, anti-dendritic cell-limbic system-associated membrane protein (anti-DC-LAMP), and anti-tryptase immunohistochemical staining was performed with 10 resected giant papillae. Human conjunctival epithelial (HCJE) cells were stimulated with poly I:C, with and without endosomal inhibitor, to examine TSLP mRNA expression. Cultured human mast cells were stimulated with recombinant (r)TSLP to analyze the downstream effect of TSLP.. All four VKC/AKC samples showed TSLP mRNA expression; however, no TSLP mRNA expression was found in the control conjunctivae. Anti-TSLP immunohistochemical staining showed preferential expression in the epithelial cells and some infiltrated cells of the giant papillae, but not in the control conjunctivae. Double immunohistochemical staining with TSLP and DC-LAMP or tryptase showed the existence of activated dendritic cells and mast cells near TSLP-positive cells in the giant papillae. Real-time PCR analysis showed that poly I:C induced TSLP mRNA expression in HCJEs in an endosomal-function-dependent manner and that rTSLP could induce IL-13 mRNA expression in the mast cells synergistically with IL-33.. The TSLP protein produced in conjunctival epithelial cells plays a role in severe ocular allergy through the activation of dendritic cells and mast cells in synergy with other cytokines.

Topics: Adolescent; Adult; Aged; Cell Adhesion Molecules, Neuronal; Child; Chronic Disease; Conjunctivitis, Allergic; Cytokines; Dendritic Cells; Epithelial Cells; Female; Fluorescent Antibody Technique, Indirect; Gene Expression Regulation; GPI-Linked Proteins; Humans; Interleukin-33; Interleukin-7; Interleukins; Macrolides; Male; Mast Cells; Middle Aged; Poly I-C; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Stromal Cells; Thymic Stromal Lymphopoietin; Thymus Gland; Tryptases; Young Adult

During metabolic alkalosis (MA) associated with 2 days of dietary chloride restriction, there is net bicarbonate secretion by rat distal tubules in vivo, whereas after 5 wk of chloride depletion alkalosis there is net bicarbonate reabsorption. To examine unidirectional components of net bicarbonate reabsorption during chronic MA, we measured distal tubule unidirectional bicarbonate secretion (Jsec) and reabsorption (Jreab), as well as the inhibitor sensitivity of Jreab. In control, 2-day, and 7-day alkalosis, Jsec was similar. Jreab, however, was only present in 7-day MA (17 +/- 3 pmol.min-1.mm-1, P < 0.05). This Jreab was completely suppressed by perfusion with 10(-7) M bafilomycin A1, partially suppressed with 10(-5) M Schering (Sch)-28080 (4 +/- 2 pmol.min-1.mm-1, P < 0.1), and converted into a secretory flux by 3 mM amiloride. We conclude that adaptation to chloride depletion MA from the acute secretory phase to the chronic state, where plasma bicarbonate is sustained at elevated levels, does not involve suppression of distal tubule Jsec but rather enhanced Jreab, which is sensitive to bafilomycin, Sch-28080, and amiloride.

Topics: Absorption; Acute Disease; Alkalosis; Amiloride; Animals; Anti-Bacterial Agents; Bicarbonates; Chronic Disease; Imidazoles; Kidney Tubules, Distal; Macrolides; Male; Perfusion; Rats; Rats, Sprague-Dawley