IL-17(+) T cells can be readily detected among activated autoreactive and bystander T cells and may play a major role in the pathogenesis of EAU.

These in vitro findings support that ROS regulate the immune response by stimulating the antigen-presenting ability of glial cells and functioning as costimulatory molecules for antigen presentation.

Background Previous studies have demonstrated that isoflurane can provide both neuroprotection and neurotoxicity in various tissue culture models and in rodent developing brains. The cellular and molecular mechanisms mediating these dual effects are not clear, but the exposure level and duration of isoflurane appear to be determinant factors. Methods Using the ReNcell CX human neural progenitor cell line, we investigated the impact of prolonged exposure to varying isoflurane concentrations on cell survival and neurogenesis. In addition, we assessed the impact of short isoflurane preconditioning on elevation of cytosolic Ca2+ concentration and cytotoxic effects mediated by prolonged isoflurane exposures and the contribution of InsP3 or ryanodine receptors activation to these processes. Results Short exposures to low isoflurane concentrations promote proliferation and differentiation of ReNcell CX cells, with no cell damage. However, prolonged exposures to high isoflurane concentrations induced significant ReNcell CX cell damage and inhibited cell proliferation. These prolonged exposures suppressed neuronal cell fate, while promoting glial cell fate. Preconditioning of ReNcell CX cultures with short exposures to low concentrations of isoflurane ameliorated the effects of prolonged exposures to isoflurane. Pretreatment of ReNcell cultures with InsP3 or ryanodine receptor antagonists mostly prevented isoflurane-mediated effects on survival, proliferation, and differentiation. Finally, isoflurane preconditioned cultures showed significantly less isoflurane-evoked changes in calcium concentration. Conclusion The commonly used general anesthetic isoflurane exerts dual effects on neuronal stem cell survival, proliferation and differentiation, which may be attributed to differential regulation of calcium release through activation of endoplasmic reticulum localized InsP3 and/or ryanodine receptors.

In a previous study, we demonstrated that immunization with the uveitogenic peptide interphotoreceptor retinoid-binding protein (IRBP) 1–20 induces both CD4 and CD8 uveitogenic T cells in the B6 mouse. In the current study, we determined the role of the CD8 IRBP-specific T cells in the pathogenesis of experimental autoimmune uveitis. We also determined the conditions that facilitated the activation of CD8 autoreactive T cells. Our results showed that the β2-microglobulin−/− mouse had a greatly decreased susceptibility to induction of experimental autoimmune uveitis by adoptive transfer of IRBP-specific T cells from B6 mice. We also showed that unlike CD4 autoreactive T cells, activated CD8 autoreactive T cells produced only a limited number and amounts of growth factors. As a result, in the absence of exogenously supplied growth factor(s), CD8 T cell activation and expansion were aborted. However, the growth and expansion of triggered CD8 autoreactive T cells could be supported by various cytokines. In addition to factors produced by activated CD4 autoreactive T cells, factors produced by nonlymphoid cells, such as IL-7 and IL-15, and unidentified factors in the culture supernatants of astrocytes and retinal pigment epithelial cells support the CD8 autoreactive T cells as well. Finally, we showed that, although several cytokines augmented the CD8 T cell response in vitro, different cytokines appeared to act on different CD8 subsets or on different activation/differentiation phases of CD8 autoreactive T cells. As a result, cytokines, such as IL-7, supported the proliferation and survival of CD8 IRBP-specific T cells, while others had only a growth-promoting effect.

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Background: The pathogenesis of multiple sclerosis (MS) is mediated primarily by T cells, but most studies of MS and its animal model, experimental autoimmune encephalomyelitis (EAE), have focused on CD4 + T cells. The aims of the current study were to determine the pathological interrelationship between CD4 and CD8 autoreactive T cells in MS/EAE. Methods: Female C57BL/6 mice (n = 20) were induced by myelin oligodendrocyte glycoprotein (MOG) 35-55 peptide. At 14 days after immunization, T cells were isolated from the spleen and purified as CD4 + and CD8 + T cells by using CD4 and CD8 isolation kits, and then the purity was determined by flow cytometric analysis. These cells were stimulated by MOG 35-55 peptide and applied to proliferation assays. The interferon-gamma (IFN-g) and interleukin (IL)-4 secretion of supernatant of cultured CD4 + and CD8 + T cells were measured by enzyme-linked immunosorbent assays (ELISA). For adoptive transfer, recipient mice were injected with MOG 35-55 -specific CD8 + or CD4 + T cells. EAE clinical course was measured by EAE score at 0-5 scale and spinal cord was examined by staining with hematoxylin and eosin and Luxol fast blue staining. Results: CD8 + CD3 + and CD4 + CD3 + cells were 86% and 94% pure of total CD3 + cells after CD8/CD4 bead enrichment, respectively. These cells were stimulated by MOG 35-55 peptide and applied to proliferation assays. Although the CD8 + T cells had a generally lower response to MOG 35-55 than CD4 + T cells, the response of CD8 + T cells was not always dependent on CD4. CD8 + T cell secreted less IFN-g and IL-4 compared with CD4 + T cells. EAE was induced in wildtype B6 naïve mice by adoptive transfer of MOG 35-55 -specific T cells from B6 active-induced EAE (aEAE) mice. A similar EAE score and slight inflammation and demyelination were found in naive B6 mice after transferring of CD8 + T cells from immunized B6 mice compared with transfer of CD4 + T cells. Conclusion: Our data suggest that CD8 + autoreactive T cells in EAE have a lower encephalitogenic function but are unique and independent on pathogenic of EAE rather than their CD4 + counterparts.

We previously demonstrated that cultures of rat uveitogenic T cells rapidly become dominated by CD4+ cells, but activation of CD8+ autoreactive T cells also occurred during the in vitro culture of in vivo-primed T cells. In the present study, we show that the commonly used uveitogenic peptide, interphotoreceptor retinoid-binding protein (IRBP) 1–20, generated both CD4+ and CD8+ autoreactive T cells in the C57BL/6 (B6) mouse and that this 20-mer contains at least two distinct antigenic epitopes. To determine whether the CD8 response was Ag-specific and whether CD4+ and CD8+ IRBP1–20-specific T cells recognize distinct antigenic epitopes, we prepared highly purified CD4+ and CD8+ T cells from IRBP1–20-primed mice and tested their proliferative response to a large panel of truncated peptides derived from IRBP1–20. The results showed that both CD4+ and CD8+ T cells recognized the same spectrum of peptides. In addition, peptides P10–18 were found to bind effectively to CD8+ IRBP1–20-specific T cells when complexed with recombinant H-2Kb and also stimulate the proliferation and cytokine production of CD4+ IRBP1–20-specific T cells. Our results document for the first time that CD8+ and CD4+ autoreactive T cells display characteristic epitope recognition and they both recognize the same core epitope.

About 80% of Chinese persons with POAG identified in a population-based study had maximum IOPs of 21 mm Hg or less over a 24-hour period. Twenty-four-hour IOP was similar between glaucomatous and contralateral nonglaucomatous eyes suggesting that factors other than IOP may play a role in the development of glaucomatous optic neuropathy in these eyes.