Anti-candida mucosal immunity

This study analyzes the phenotype of vaginal dendritic cells (VDCs), their antigenic presentation and activation of T-cell cytokine secretion, and their protective role in a rat model of Candida vaginitis. Histological observation demonstrated a significant accumulation of OX62+ VDCs in the mucosal epithelium of Candida albicans-infected rats at the third round of infection.\ud We identified two subsets of OX62+ VDCs differing in the\ud expression of CD4 molecule in both noninfected and Candida infected rats. The OX62+ CD4+ subset of VDCs displayed a lymphoid cell-like morphology and expressed the T-cell\ud antigen CD5, whereas the OX62+ CD4-VDC subset exhibited a\ud myeloid morphology and was CD5 negative. Candida infection\ud resulted in VDC maturation with enhanced expression of CD80 and CD134L on both CD4+ and CD4- VDC subsets at 2 and 6 weeks after Candida infection. CD5- CD4- CD86- CD80- CD134L+ VDCs from infected, but not noninfected, rats spontaneously released large amounts of interleukin-12 (IL-12) and tumor necrosis factor alpha, whereas all VDC subsets released comparable levels of IL-10 and IL-2 cytokines. Furthermore, OX62+ VDCs from infected rats\ud primed naive CD4+ T-cell proliferation and release of cytokines, including gamma interferon, IL-2, IL-6, and IL-10, in response to staphylococcal enterotoxin B stimulation in vitro.\ud Adoptive transfer of highly purified OX62+ VDCs from infected rats induced a significant acceleration of fungal clearance compared with that in rats receiving naive VDCs, suggesting a protective role of VDCs in the anti-Candida mucosal immunity. Finally, VDC mediated protection was associated with their ability to rapidly migrate to the\ud vaginal mucosa and lymph nodes, as assessed by adoptive transfer of OX62+ VDCs labeled with 5 (and 6-)-carboxyfluorescein diacetate succinimidyl ester.\ud \u

Sprawl e trasformazioni urbane. Un contributo dalla sociologia

Questo contributo rappresenta uno sforzo interdisciplinare di comprensione del processo di trasformazione, dei suoi meccanismi generatori, degli effetti sociali, ambientali, economici alle opportune di scale di lettura dello sprawl urbano. Rispetto a questo obiettivo, questo saggio offre una breve riflessione intorno al contributo che la sociologia urbana può offrire allo studio dello sprawl o, più opportunamente, ai mutamenti urbani e metropolitani. Una sociologia che non guarda più allo spazio prima che al cambiamento sociale, e che sottolinea con forza l’esigenza del dialogo tra discipline su uno dei più discussi temi dei nostri anni.The aim of the paper is to discuss the concept of urban sprawl, trying to set it in the most general process of city growth and development. This paper argues for the use of a new approach in which sprawl is analywed in a multidisciplinary perspectiv

Candida albicans Expresses a Focal Adhesion Kinase-Like Protein That Undergoes Increased Tyrosine Phosphorylation upon Yeast Cell Adhesion to Vitronectin and the EA.hy 926 Human Endothelial Cell Line

The signaling pathways triggered by adherence of Candida albicans to the host cells or extracellular matrix are poorly understood. We provide here evidence in C. albicans yeasts of a p105 focal adhesion kinase (Fak)-like protein (that we termed CaFak), antigenically related to the vertebrate p125Fak, and its involvement in integrin-like-mediated fungus adhesion to vitronectin (VN) and EA.hy 926 human endothelial cell line. Biochemical analysis with different anti-chicken Fak antibodies identified CaFak as a 105-kDa protein and immunofluorescence and cytofluorimetric analysis on permeabilized cells specifically stain C. albicans yeasts; moreover, confocal microscopy evidences CaFak as a cytosolic protein that colocalizes on the membrane with the integrin-like VN receptors upon yeast adhesion to VN. The protein tyrosine kinase (PTK) inhibitors genistein and herbimycin A strongly inhibited C. albicans yeast adhesion to VN and EA.hy 926 endothelial cells. Moreover, engagement of αvβ3 and αvβ5 integrin-like on C. albicans either by specific monoclonal antibodies or upon adhesion to VN or EA.hy 926 endothelial cells stimulates CaFak tyrosine phosphorylation that is blocked by PTK inhibitor. A role for CaFak in C. albicans yeast adhesion was also supported by the failure of VN to stimulate its tyrosine phosphorylation in a C. albicans mutant showing normal levels of CaFak and VNR-like integrins but displaying reduced adhesiveness to VN and EA.hy 926 endothelial cells. Our results suggest that C. albicans Fak-like protein is involved in the control of yeast cell adhesion to VN and endothelial cells

Immune Cell-Mediated Protection against Vaginal Candidiasis: Evidence for a Major Role of Vaginal CD4(+) T Cells and Possible Participation of Other Local Lymphocyte Effectors

The protective roles of different lymphocyte subsets were investigated in a rat vaginal candidiasis model by adoptive transfer of vaginal lymphocytes (VL) or sorted, purified CD3(+) T cells, CD4(+) or CD8(+) T cells, or CD3(−) CD5(+) B cells from the vaginas of naïve or immune rats following three rounds of Candida albicans infection. The adoptive transfer of total VL from nonimmune animals did not alter the course of vaginal candidiasis of the recipient rats. In contrast, the animals receiving total VL or CD3(+) T cells from immune rats showed a highly significant acceleration of fungus clearance compared with animals which received nonimmune VL. The animals with vaginal CD3(−) CD5(+) B cells transferred from immune rats also had fewer Candida CFU than the controls, but fungal clearance was significantly retarded with respect to the animals administered immune T cells. Sorted, purified CD4(+) and CD8(+) vaginal T cells from immune rats were also adoptively transferred to naïve animals. Although both populations were seen to accelerate the clearance of the fungus from the vagina, CD4(+) T cells were much more effective than CD8(+) T cells. Overall, there was no difference between the antifungal effects of immune vaginal CD4(+) T cells and those achievable with the transfer of whole, immune VL. Histological observations of the vaginal tissues of rats with adoptively transferred immune T cells demonstrated a remarkable accumulation of lymphocytes in the subepithelial lamina propria and also infiltrating the mucosal epithelium. These results strongly suggest that distinct vaginal lymphocyte subsets participate in the adaptive anti-Candida immunity at the vaginal level, with the vaginal CD4(+) T cells probably playing a major role

Phenotypic and Functional Characterization of Vaginal Dendritic Cells in a Rat Model of Candida albicans Vaginitis

This study analyzes the phenotype of vaginal dendritic cells (VDCs), their antigenic presentation and activation of T-cell cytokine secretion, and their protective role in a rat model of Candida vaginitis. Histological observation demonstrated a significant accumulation of OX62(+) VDCs in the mucosal epithelium of Candida albicans-infected rats at the third round of infection. We identified two subsets of OX62(+) VDCs differing in the expression of CD4 molecule in both noninfected and Candida-infected rats. The OX62(+) CD4(+) subset of VDCs displayed a lymphoid cell-like morphology and expressed the T-cell antigen CD5, whereas the OX62(+) CD4(−) VDC subset exhibited a myeloid morphology and was CD5 negative. Candida infection resulted in VDC maturation with enhanced expression of CD80 and CD134L on both CD4(+) and CD4(−) VDC subsets at 2 and 6 weeks after Candida infection. CD5(−) CD4(−) CD86(−) CD80(−) CD134L(+) VDCs from infected, but not noninfected, rats spontaneously released large amounts of interleukin-12 (IL-12) and tumor necrosis factor alpha, whereas all VDC subsets released comparable levels of IL-10 and IL-2 cytokines. Furthermore, OX62(+) VDCs from infected rats primed naïve CD4(+) T-cell proliferation and release of cytokines, including gamma interferon, IL-2, IL-6, and IL-10, in response to staphylococcal enterotoxin B stimulation in vitro. Adoptive transfer of highly purified OX62(+) VDCs from infected rats induced a significant acceleration of fungal clearance compared with that in rats receiving naive VDCs, suggesting a protective role of VDCs in the anti-Candida mucosal immunity. Finally, VDC-mediated protection was associated with their ability to rapidly migrate to the vaginal mucosa and lymph nodes, as assessed by adoptive transfer of OX62(+) VDCs labeled with 5 (and 6-)-carboxyfluorescein diacetate succinimidyl ester