In the present work, we have examined the effect of PAF, removal of epithelium, the mechanism of desensitization, and the substances that increases the level of intracellular c-AMP on the differences of mediator release from superfused tracheal strips after passive sensitization with IgG1 versus IgE Ab. In the passive sensitized tracheal tissues, the effect of PAF and the mechanism of desensitization have been examined by PAF antagonist, CV 3988 and DFP, respectively. The epithelium was stripped from one-half of each trachea by mechanical means. Both superfused tracheal tissues were challenged with Ox-Ag. Inhibitors of mediator release were added into a superfused buffer. Hist released was determined by spectrophotofluorometer, and LT by radioimmunoassay. PAF known to mediate the allergic reaction was not released by Ag after both Ab sensitization. Epithelium removal resulted in similar contraction, Hist and LT release after IgG1 Ab activation, but in the IgE Ab activation, epithelium removal resulted in smaller contraction and Hist release. In the L-cysteine and indomethacin pretreatment after two Ab sensitization, epithelium removal decreased the release of Hist and LT. The compound 48/80 pre-challenge and epithelium removal resulted in the increase of Hist release, but in the decrease of LT release after IgG1 or IgE sensitization. The Amount of LT released by Ag after compound 48/80 pre-challenge increased in the absence or presence of epithelium after both Ab sensitization. Mediator release from tissues sensitized with both Abs was not changed by DFP. The responses of inhibitors to prevent the mediator release were more effective on the IgE Ab than on the IgG1 Ab sensitization. These studies suggest that the tracheal epithelium can act to inhibit immune- and non-immune-induced airway responses. Non-immunological responses may in part reflect the role of epithelium as a diffusion barrier and modulator of mediator release. These data also suggest that immunological responses are related to the localization and functional heterogeneity of tissue mast cells.
Animal ; Epithelium/immunology/physiology ; Female ; Guinea Pigs ; *Histamine Release ; *Immunization ; Immunoglobulin E/*immunology ; Immunoglobulin G/*immunology ; Leukotrienes/metabolism ; Mast Cells/immunology ; Support, Non-U.S. Gov't ; Trachea/*immunology/physiology

The regulated transport of salt and water is essential to the integrated function of many organ systems, including the respiratory, reproductive, and digestive tracts. Airway epithelial fluid secretion is a passive process that is driven by osmotic forces, which are generated by ion transport. The main determinant of a luminally-directed osmotic gradient is the mucosal transport of chloride ions (Cl(-)) into the lumen. As with many epithelial cells, a number of classic signal transduction cascades are involved in the regulation of ion transport. There are two well-known intracellular signaling systems: an increase in intracellular Ca(2+) concentration ([Ca(2+)]i) and an increase in the rate of synthesis of cyclic nucleotides, such as cyclic adenosine monophosphate (cAMP). Therefore, Cl(-) secretion is primarily activated via the opening of apical Ca(2+)- or cAMP-dependent Cl(-) channels at the apical membrane. The opening of basolateral Ca(2+)- or cAMP-activated K(+) channels, which hyperpolarizes the cell to maintain the driving force for Cl(-) exit through apical Cl(-) channels that are constitutively open, is also important in regulating transepithelial ion transport. P2Y receptors are expressed in the apical and/or basolateral membranes of virtually all polarized epithelia to control the transport of fluid and electrolytes. Human airway epithelial cells express multiple nucleotide receptors. Extracellular nucleotides, such as UTP and ATP, are calcium-mobilizing secretagogues. They are released into the extracellular space from airway epithelial cells and act on the same cell in an autocrine fashion to stimulate transepithelial ion transport. In addition, recent data support the role of P2Y receptors in releasing inflammatory cytokines in the bronchial epithelium and other immune cells.
Biological Transport ; Cell Membrane ; physiology ; Chloride Channels ; physiology ; Cyclic AMP ; physiology ; Cytokines ; immunology ; Epithelial Cells ; physiology ; Epithelium ; immunology ; physiology ; Humans ; Ion Transport ; Receptors, Purinergic P2Y ; immunology ; physiology ; Signal Transduction

BACKGROUNDCornea epithelial cells play early and crucial roles in the initiation of ocular surface responses to pathogens. Participation of toll-like receptor (TLR) 2 and TLR4, which are major forms of fungi receptors, may be involved in Aspergillus fumigatus induced immune responses. The objective of the present study was to examine whether inactive Aspergillus fumigatus conidia induce NF-kappaB activation and production of proinflammatory cytokines, and whether the expression of TLR2 and TLR4 were amplified by conidia in cultured immortalized human corneal epithelial cells (THCEs). This may contribute to our knowledge of the mechanism by which the host cornea can successfully defend against invasive fungi.

METHODSAspergillus fumigatus conidia were used to challenge THCE cells. THCE cells were harvested after 0.5, 1, 2 or 4 hours incubation. Real-time quantitative PCR was performed to determine the expression of TLR2, TLR4, TNF-alpha and IL-8. Western blotting was performed to determine the expression of NF-kappaB. Enzyme-linked immunosorbent assay (ELISA) was performed to determine the expression of TNF-alpha and IL-8. And the release of TNF-alpha and IL-8 in the cell supernatant were also assessed by ELISA with or without pretreatment with TLR2 and TLR4 neutralizing antibodies.

RESULTSAspergillus fumigatus conidia elicited the expression of TLR2, TLR4, TNF-alpha and IL-8 mRNA in THCEs. Exposure of THCE cells to Aspergillus fumigatus conidia resulted in NF-kappaB activation, which increased at 30 minutes (increased from 11.35+/-2.74 in the controls to 19.12+/-3.48, P<0.05) and thereafter increased steadily up to 4 hours after challenge (P<0.01). Concomitant with NF-kappaB activation, secretion of TNF-alpha and IL-8 in conidia-challenged cells was increased in a time-dependent manner. Incubation of THCE cells with TLR2 antibody or TLR4 antibody before conidia challenge resulted in inhibition of conidia-induced TNF-alpha and IL-8 secretion (P<0.05), TLR2 antibody and TLR4 antibody together significantly increased inhibition of the conidia-induced secretion of TNF-alpha and IL-8 from THCE cells (P<0.01).

CONCLUSIONAspergillus fumigatus conidia stimulates THCEs inflammatory response through a pathway dependent on TLR2 and TLR4 signaling.

Aspergillus fumigatus ; immunology ; Cells, Cultured ; Epithelium, Corneal ; cytology ; immunology ; Humans ; Interleukin-8 ; biosynthesis ; NF-kappa B ; metabolism ; Toll-Like Receptor 2 ; physiology ; Toll-Like Receptor 4 ; physiology ; Tumor Necrosis Factor-alpha ; biosynthesis

AIMTo understand the biological functions of the ectoplasmic specializations between Sertoli cells and maturing spermatids in seminiferous epithelia.

METHODSIn order to disrupt the function of the ectoplasmic specializations, nectin-2, which is expressed at the specialization, was neutralized with anti-nectin-2 antibody micro-injected into the lumen of the mouse seminiferous tubule. Anti-nectin-3 antibody was also micro-injected into the lumen in order to neutralize nectin-3, which is expressed at the specialization.

RESULTSThe actin filaments at the specialization disappeared, and exfoliation of maturing spermatids was observed by electron microscopy.

CONCLUSIONNectin-2 was neutralized by anti-nectin-2 antibody and nectin-3 was neutralized by anti-nectin-3 antibody, respectively. Inactivated nectin-2 and nectin-3 disrupted the nectin-afadin-actin system, and finally the actin filaments disappeared. As a result, the specialization lost the holding function and detachment of spermatids was observed. One of the functions of the specialization seems to be to hold maturing spermatids until spermiation.

Actins ; metabolism ; Animals ; Antibodies ; immunology ; pharmacology ; Cell Adhesion Molecules ; immunology ; metabolism ; Cell Communication ; drug effects ; physiology ; Intercellular Junctions ; drug effects ; metabolism ; Male ; Mice ; Mice, Inbred ICR ; Microfilament Proteins ; metabolism ; Microscopy, Confocal ; Nectins ; Seminiferous Epithelium ; cytology ; drug effects ; metabolism ; Sertoli Cells ; cytology ; drug effects ; metabolism ; Spermatids ; cytology ; drug effects ; metabolism

OBJECTIVETo investigate the blockness effects of purified polyclonal anti-porin I antibody on N. gonorrhoeae adherence to genitourinary tract epithelia of BALB/c mouse.

METHODSPolyclonal anti GST-PI antibody was generated by immunizing rabbit with GST-PI fusion protein which was constructed and expressed by ourselves. The purified immunoglobulin G was obtained by ammonium sulphate deposition and DEAE cellulose chromatography. Mice model of gonorrhea was established. In order to evaluate the effects of PI-IgG on gonococcus adhesion to vagina mucus, the macroscopic and pathological assessing as well as gonococcus culture was employed after gonococcus challenge on PI-IgG immunized mice.

RESULTNo pus and pathological inflammation were observed on mice vagina mucus treated with 1 mg/ml PI-IgG 3 hours before gonococcus challenge. Gonococcus could not be detected in the smears and washing solutions from vagina. Pathological inflammation was found in mice treated with anti PI-IgG, in which the concentrations were lower than 1 mg/ml or the treated time was longer than 3 hours prior to gonococcus challenge.

CONCLUSIONThe purified anti PI-IgG can effectively inhibit the adherence and infection of gonococci to genitourinary tract epithelia of BALB/c mice. In addition, the blocking duration of anti PI-IgG is associated with antibody concentration.

Animals ; Antibodies, Monoclonal ; pharmacology ; Bacterial Adhesion ; drug effects ; Epithelium ; drug effects ; microbiology ; Female ; Glutathione Transferase ; biosynthesis ; genetics ; Gonorrhea ; microbiology ; prevention & control ; Mice ; Mice, Inbred BALB C ; Neisseria gonorrhoeae ; drug effects ; physiology ; Porins ; biosynthesis ; genetics ; immunology ; Rabbits ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; immunology ; Urogenital System ; drug effects ; microbiology