Colapso del inmunoprivilegio y estrés emocional en Alopecia Areata / Collapse of the immunoprivilege and emotional stress in alopecia areata

Resumen El folículo piloso es una estructura compleja que presenta diversas características morfológicas macroscópicas, microscópicas e inmunológicas especiales que permiten el adecuado funcionamiento de la misma, en algunasenfermedades estos mecanismos de regulación inmunológica se ven alteradose incluso exacerbados por factores como el estrés emocional. El objetivo de esta revisión es conocer los mecanismos inmunobiológicos específicos del folículo pilosoanalizando el papel que juegan diversos factores como la pérdida delinmunoprivilegio y el estrés emocional en el desarrollo de la alopecia areata.

Abstract The hair follicle is a complex structure that presents diverse morphologicaland immunological characteristics that allow the proper functioning of the unit.In some diseases as alopecia areata these mechanisms of immune regulation are disrupted by external factorssuch as emotional stress preventing the growth of the hair shaft. The objective of this review is to recognize the specific immunobiological mechanisms of the hair follicle, analyzing the role played by the loss of immunoprivilege and emotional stress in the development of alopecia areata.

Dynamic changes of FasL protein expression in retinal tissue with aging in retinal degeneration mice / 中华实验眼科杂志

Background Retinal transplantation is a new approach to the treatment of retinal degeneration diseases,and how to avoid or reduce the immune rejection after transplantation is a problem.In experimental studies on retinal transplantation,C57BL/6 mice are often used as donors and rd mice serve as recipients.Studies showed that Fas ligand (FasL) protein induces the apoptosis of Fas+ inflammatory cells by FasL/Fas signal pathway,speculating that FasL protein is associated with immune rejection after transplantation.Objective The aim of this study was to investigate FasL protein expression change in retinas of C57BL/6 mice and rd mice with aging and reveal the immune characteristics of the mouse retinas.Methods The frozen sections of eyeball from C57BL/6 mice and rd mice at the age of postnatal (PN)-0 week,PN-1 week,PN-2 week,PN-3 week and PN-4 week were prepared.The expression of FasL protein in the mouse retinas was examined by immnofluorescense technique.Images were acquired by fluorescence microscope and analyzed semi-quantitively by software from laser scanning confocal microscope as the fluorescence intensity (FI).The results were compared among different strains of mice.Results The retina developed imperfectly in PN-1 week C57BL/6 mice and FasL protein was positively expressed in the whole retina.In PN-2,3 and 4 week C57BL/6 mice,retinas finished the development with 10 layers,and retinal pigment epithelium (RPE),inner segment (IS),outer limiting membrane (OLM),outer plexiform layer (OPL),inner nuclear layer (INL),inner plexiform layer (IPL) and ganglion cell layer (GCL).Retinal structure and expression of FasL protein in the whole retina of rd mice in the PN-1 week were similar with C57BL/6 mice,however,ONL cells of rd mice were evidently decreased with aging.The RPE,OPL,INL,IPL and GCL expressed the FasL protein in PN-2,PN-3 and PN-4 week rd mice.The mean FI of FasL protein in the RPE layer was 184.199±16.747,186.797±7.904 and 184.319± 18.795 in rd mice of PN-2 week,PN-3 week and PN-4 week,which were significantly higher than 160.402±22.851,160.995 ±22.799 and 105.787 ± 17.676 in C57BL/6 mice (t =-3.360,P =0.002;t'=-4.277,P =0.000;t =-12.175,P=0.000).There were not significant differences in the mean FI of FasL protein in IPL between C57BL/6 mice and rd mice at ages of PN-2 week,PN-3 week and PN-4 week (all at P＞0.05).Conclusions The cells of retinal ONL are gradually decreased with the development of rd mice,and FasL protein expression intensity in RPE is evidently enhanced in rd mice compared with C57BL/6 mice.

Relative tolerance of lung in murine model of acute graft-versus-host disease / 中华器官移植杂志

Objective To analyze the immune privilege of lung in acute graft-versus-host disease (aGVHD).Methods The models of aGVHD were established,and C57BL/6J→C57BL/6J model was used as control.The clinical scores and survival were observe& The pathological injuries were compared between the lung and traditional target organs (liver,small intestines and skin).The expression of IFN-γ in different organs after transplantation was detected by ELISA.Results Allogeneic hematopoietic stem cell transplantation (HSCT) mice had high 42-day survival rate (20 ％) post-transplantation,and recipients of allogeneic grafts showed classical symptoms and histological injury,and pathological changes of lung were not as serious as the liver,small intestine,skin at day 28 after transplantation.Syngeneic mice all survived at day 42 after transplantation,without GVHD symptoms and pathological changes.The mice in MHC-disparate mice (2 ∶ 1 and 4 ∶ 1 groups) died significantly faster at a median of 12 days after transplantation,with severe changes of clinical symptoms and pathology of classical organs,and MHC-disparate mice (4∶1 groups) had developed severe interstitial pneumonitis.The mean IFN-γ concentration in the lung of allogeneic HSCT mice was obviously increased in the first and second week after transplantation,the IFN-γ concentrations of target organs (liver,small intestines,skin) were slightly increased in the first and second week after transplantation,and there were statistically significant difference from lung (P＜0.05).Condmion There wasrelativeimmune privilege of lung in a murine model of aGVHD induced by HSCT,which was associated with the expression of MHCin the mice and IFN-gamma of lungs after transplantation.

Research advances in corneal newborn lymphatic vessel and corneal transplantation rejection / 国际眼科杂志(Guoji Yanke Zazhi)

Corneal newborn lymphatic vessels construct the afferent arc of corneal immunological reaction, which play important role in immune response. The corneal transplantation rejection rate rises due to the emergence of new lymphatic vessel which breaks the immunologic mechanism. With the founding of specific marker of lymphatic endothelial cells and research advancing of growth factor of lymphatic vessels, the mechanism, therapy and prevention of corneal immunological rejection reaction of corneal lymphatic vessel have been studied intensively. The graft survival rate has been greatly improved through inhibiting newborn lymphatic vessel.

Testis immune privilege - Assumptions versus facts

The testis has long enjoyed a reputation as a n immunologically privileged site based on its ability to protect auto - antigenic germ cells and provide an optimal environment for the extended survival of transplanted allo - or xeno - grafts. Exploration of the role of anatomical, physiological, immunologica l and cell ular components in testis immune privilege reveal ed that the tolerogenic environment of the test i s is a result of the immunomodulatory factors expressed or secreted by testicular cells (mainly Sertoli cells, peritubular myoid cells, Leydig cells , and resident macrophages ). The b lood - testis barrier/Sertoli cell barrier, is also important to seclude advanced germ cells but its requirement in testis immune privilege needs further investigation . T esticular immune privilege is not permanent , as an effe ctive immune response can be mounted against transplanted tissue , and bacterial/viral infections in the testis can be effectively eliminated . Overall, the cellular components control the fate of the immune response and can shift the response from immunodestructive to immunoprotective, resulting in immuneprivilege.

Effect of topical tacrolimus on xenogeneic hair follicle transplantation / 中华医学美学美容杂志

Objective To study the effect of topical tacrolimus (FK506) on the survival of the xenogeneic transplanted hair follicles from human scalp to Wistar rats. Methods In our study, Wistar rats were used as recipients and human as donor. The black hair follicles of human scalp were harvested, and then the xenogeneic grafts were transplanted to white Wistar rats on the back. 20 couples of rats were divided in 2 groups: topical tacrolimus group (group A), and blank control group (group B). After operaton, we compared the survival time of hair follicles and their histologic outcomes in order to verify the practicability of xenogeneic transplantion of hair follicles, and the topical application of tacrolimus results.Results The mean survival time of group A was longer [(49. 9 ±7. 1) days] as compared to group B [(13. 1±1. 2) days]. The longest survival time was 65 days in group A and 14 days in group B, respectively. By comparison of the results we found that topical tacrolimus prolonged the survival time of the xenotransplanted hair follicles significantly and that tropical medication could not avoid rejection. Conclusions The immune privilege function dependent on the hair follicle anagen and axillary topical tacrolimus, can prolong the survival time of the xenogeneic transplanted hair follicles in rats significantly.

Mechanism of Humoral and Cellular Immune Modulation Provided by Porcine Sertoli Cells

The understanding of main mechanisms that determine the ability of immune privilege related to Sertoli cells (SCs) will provide clues for promoting a local tolerogenic environment. In this study, we evaluated the property of humoral and cellular immune response modulation provided by porcine SCs. Porcine SCs were resistant to human antibody and complement-mediated formation of the membrane attack complex (38.41+/-2.77% vs. 55.02+/-5.44%, p=0.027) and cell lysis (42.95+/-1.75% vs. 87.99 +/-2.25%, p<0.001) compared to immortalized aortic endothelial cells, suggesting that porcine SCs are able to escape cellular lysis associated with complement activation by producing one or more immunoprotective factors that may be capable of inhibiting membrane attack complex formation. On the other hand, porcine SCs and their culture supernatant suppressed the up-regulation of CD40 expression (p<0.05) on DCs in the presence of LPS stimulation. These novel findings, as we know, suggest that immune modulatory effects of porcine SCs in the presence of other antigen can be obtained from the first step of antigen presentation. These might open optimistic perspectives for the use of porcine SCs in tolerance induction eliminating the need for chronic immunosuppressive drugs.

Expression of Local Immunosuppressive Factor, Indoleamine 2,3-dixygenase, in Human Coreal Cells

PURPOSE: To identify the localization of indoleamine 2,3-dioxygenase (IDO) in human corneal cells and to evaluate its ability to act as a local immunosuppressive factor. METHODS: The expression profile of IDO was obtained with RT-PCR and Western blot of in a primary culture of human corneal cells (fibroblasts, epithelial cells and endothelial cells). In order to investigate the immunosuppressive function of IDO, immune cells were cultured in a human corneal cell-conditioned medium, and their prolifleration was identified by the MTT assay. Moreover, apoptotic effects of IDO in immune cells treated with IFN-gamma were also investigated with apoptosis ELISA. RESULTS: Among the three different types of human corneal cells analyzed, mRNA and protein expression of IDO was observed only in human corneal fibroblasts. Immune cells cultured in a human corneal fibroblast-conditioned medium showed inhibited proliferation. Moreover, IFN-gamma-induced expression of IDO significantly enhanced apoptotic ability in a dose-depandant manner. CONCLUSIONS: Our results suggest that human corneal fibroblasts are relatively immuno-resistant and that expression of IDO may be one of the factors involved in the immune tolerance observed in corneal grafts.

Hair Cycle-associated Changes of the Immunological Markers in Human Hair Follicles / 대한피부과학회지

BACKGROUND: The immunological characteristics of human hair follicles with the hair growth cycle have not yet been fully elucidated. It is suggested that expressional changes of the immunological markers in the hair cycle may play a role in catagen induction of the hair follicles. OBJECTIVE: To analyze the immunological features in human hair follicles according to the hair growth cycle. METHODS: An immunohistochemical study was performed on frozen sections of human hair follicles using major histocompatibility complex (MHC) class I & II, CD1a, Fas, Fas ligand, and ACTH antibodies. We then compared the hair cycle-associated expressional changes of these markers. RESULTS: Human anagen hair bulbs showed very low level of the MHC class I expression. In catagen transition, enhanced expression of the MHC class I was observed in the proximal hair follicles. This change may correspond to regressing morphological change of hair follicles in the catagen transition. Some changes in the expression of MHC class II and Fas/FasL in hair follicles were also observed in catagen transition. CONCLUSION: Downregulation of MHC class I expression in the proximal epithelium of the anagen hair bulb may contribute to so-called 'immune privilege'. In catagen transition, the expression of MHC class II and Fas/FasL, together with upregulation of MHC class I, might be related to morphologic changes of the hair follicle.

Double protecting functions of rat Sertoli cells to co-encapsulated hepatocytes in vitro / 基础医学与临床

Objective To evaluate the nourishment and immune privilege effects of Sertoli cells on co-encapsulated hepatocytes. Methods The hepatocytes and Sertoli cells were encapsulated or co-encapsulated in various ratio of 100∶1、50∶1、20∶1、10∶1, and co-cultured for 21 days in vitro. The secretion of albumin and urea was analyzed, and the morphology of encapsulated cells was observed by microscopy, then to determine the best mixed ratio of hepatocytes to Sertoli cells. Splenocyte proliferation response was assessed to evaluate Sertoli cell’s immune privilege function to hepatocytes by CCK-8.Results Sertoli cells could elevate hepatocyte’s secretion of albumin and urea when they were co-encapsulated with each in appropriate ratio (P

Prevention of experimental autoimmune anterior uveitis by anterior chamber-associated immune deviation / 眼科新进展

Objective Experimental autoimmune anterior uveitis (EAAU) is a useful model for human anterior uveitis. The purpose of this study was to observe whether EAAU development could be prevented by anterior chamber-associated immune deviation (ACAID). Methods Bovine melanin protein (BMP) in phosphate-buffered saline (PBS) was injected into the anterior chamber of the right eye of rats; control animals were injected with PBS alone. Seven days later, all animals were immunized with BMP in complete Freund's adjuvant (CFA) and pertussis toxin. The severity and incidence of uveitis was monitored by clinical examination and histopathology. The delayed-type hypersensitivity (DTH) responses were evaluated by footpad swelling elicited by injection of BMP.Results Rats intraocularly injected with BMP showed a reduced severity and incidence of EAAU, and significantly suppressed DTH response compared to control rats.Conclusion These data suggest that the ACAID procedure can be utilized to prevent the development of EAAU.

Cotransplantation of parathyroid cell and allogeneic testicular Sertoli cell induced immune privilege / 中华器官移植杂志

Objective To investigate the immune privilege of cotransplanted parathyroid cells induced by testicular Sertoli cells expressing Fas ligand (FasL).Methods Different testicular Sertoli cells and allogeneic parathyroid cells were cotransplanted respectively. Allografts survival,cells component and the apoptosis of infiltrative lymphocytes in vitro were analyzed.Results The parathyroid cells transplanted alone were all rejected with the mean survival time of ( 17.22 ? 3.63 ) days. When parathyroid cells were cotransplanted with testicular Sertoli cells,survival time of allografts was prolonged. When the quantity of testicular cells was increased to 4?10 6,most animals remained normal serum calcium and PTH throughout the follow-up period ( P