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H Keino

Publications and source records attributed to H Keino.

At least 19 recordsLinked to original sources
PubMed2006

Supplementation of CD4+CD25+ regulatory T cells suppresses experimental autoimmune uveoretinitis.

AIMS: To investigate whether supplementation of natural CD4+CD25+ regulatory T cells ameliorates mouse experimental autoimmune uveoretinitis (EAU) induced by CD4+ T cell-dependent interphotoreceptor retinoid-binding protein (IRBP). METHODS: C57BL/6 mice were immunised with human interphotoreceptor retinoid-binding protein peptide 1-20 (IRBP(1-20)), and IRBP(1-20)-sensitised T cells were obtained. CD4+CD25+ T cells derived from naive mice were cocultured with IRBP(1-20)-sensitised T cells, and their proliferation responses and cytokine production were measured. In addition, CD4+CD25+ T cells were transferred intravenously into mice 7 or 15 days after immunisation with IRBP(1-20), and the severity of EAU and T cell proliferation responses were evaluated. RESULTS: CD4+CD25+ regulatory T cells effectively inhibited both the proliferation of, and interleukin (IL)2, IL5 and interferon (IFN)gamma production by, IRBP(1-20)-sensitised T cells. Adoptive transfer of CD4+CD25+ regulatory T cells to IRBP(1-20)-immunised mice conferred considerable protection from EAU development and inhibition of T cell proliferation responses to IRBP(1-20). CONCLUSION: These findings show that natural CD4+CD25+ regulatory T cells possess the ability to inhibit activation of IRBP-reactive T cells that have been already sensitised in vivo, and adoptive transfer of these cells ameliorates EAU even in the effector phase. Supplementation of natural CD4+CD25+ regulatory T cells may have therapeutic potential for effective treatment of uveitis.

Adoptive Transfer↗
PubMed2006

Sensory system-predominant distribution of leukotriene A4 hydrolase and its colocalization with calretinin in the mouse nervous system.

Leukotriene B4 is a potent lipid mediator, which has been identified as a potent proinflammatory and immunomodulatory compound. Although there has been robust evidence indicating that leukotriene B4 is synthesized in the normal brain, detailed distribution and its functions in the nervous system have been unclear. To obtain insight into the possible neural function of leukotriene B4, we examined the immunohistochemical distribution of leukotriene A4 hydrolase, an enzyme catalyzing the final and committed step in leukotriene B4 biosynthesis, in the mouse nervous system. Immunoreactivity for leukotriene A4 hydrolase showed widespread distribution with preference to the sensory-associated structures; i.e. neurons in the olfactory epithelium and vomeronasal organ, olfactory glomeruli, possibly amacrine cells, neurons in the ganglion cell layer and three bands in the inner plexiform layer of the retina, axons in the optic nerve and tract up to the superior colliculus, inner and outer hair cells and the spiral ganglion cells in the cochlea, vestibulocochlear nerve bundle, spinal trigeminal tract, and lamina II of the spinal cord. Double immunofluorescence staining demonstrated that most of the leukotriene A4-hydrolase-immunopositive neurons coexpressed calretinin, a calcium-binding protein in neurons. The ubiquitous distribution of leukotriene A4 hydrolase was in sharp contrast with the distribution of leukotriene C4 synthase [Shimada A, Satoh M, Chiba Y, Saitoh Y, Kawamura N, Keino H, Hosokawa M, Shimizu T (2005) Highly selective localization of leukotriene C4 synthase in hypothalamic and extrahypothalamic vasopressin systems of mouse brain. Neuroscience 131:683-689] which was confined to the hypothalamic and extrahypothalamic vasopressinergic neurons. These results suggest that leukotriene B4 may exert some neuromodulatory function mainly in the sensory nervous system, in concert with calretinin.

Animals↗
PubMed2006

Apical vulnerability to dendritic retraction in prefrontal neurones of ageing SAMP10 mouse: a model of cerebral degeneration.

The SAMP10 mouse is a model of accelerated ageing in which senescence is characterized by age-related atrophy of the cerebral cortex and limbic structures, poor learning and memory task performance with depressive behaviour and cholinergic and dopaminergic alterations. Here we studied age-related changes in the dendritic arbors and spine density of pyramidal cells in the medial prefrontal cortex of SAMP10 mice using a quantitative Golgi method. Dendrites of prefrontal neurones gradually retracted with ageing towards the soma with the relative preservation of overall complexity. Apical dendrites were much more severely affected than basal dendrites. The combined length of the apical dendrites and spine density were decreased by 45% and 55%, respectively, in mice at 12 months, compared with mice at 3 months of age. Immunohistochemical and immunoblot analyses indicated that expression of microtubule-associated protein (MAP) 2, a marker of dendrites, decreased in an age-related manner not only in the anterior cortex but also in the posterior cortex and olfactory structures in SAMP10 mice. Decreased expression of MAP2 mRNA caused the decrease in MAP2 protein expression. These results suggest that retraction of apical, but not of basal dendrites, with a loss of spines in prefrontal neurones, appears to be responsible for poor learning and memory performance in aged SAMP10 mice. It is also suggested that age-related dendritic retraction occurs in a wide area including the entire cerebral cortex and olfactory structures.

Aging↗
PubMed2005

Highly selective localization of leukotriene C4 synthase in hypothalamic and extrahypothalamic vasopressin systems of mouse brain.

While leukotriene C4 (LTC4) was originally identified as a potent bronchoconstrictor, the compound has versatile biological activities besides inflammatory reactions. Although the high content of LTC4 has been reported in the hypothalamus and median eminence, the precise localization of the compound remained obscure. To elucidate its possible functions in the neuroendocrine systems, we determined immunohistochemical localization of LTC4 synthase, a key enzyme to produce LTC4 using mouse brains. Light microscopy and confocal laser scanning microscopy showed that LTC4 synthase was selectively localized in the vasopressinergic magnocellular neurons of the hypothalamic paraventricular, supraoptic and suprachiasmatic nuclei and in the retrochiasmatic area, as well as in axons that emanated from these neurons to the pars nervosa of the pituitary gland. At subcellular level, however, LTC4 synthase and arginine vasopressin appeared to localize differently within individual neurons. LTC4 synthase immunoreactivity was also observed in the axons of the extrahypothalamic system including the bed nucleus of the stria terminalis, lateral habenular nucleus, midbrain central gray, medial amygdaloid nucleus and ventral septal area, although this immunoreactivity was relatively minor. The other brain regions did not contain LTC4 synthase immunoreactivity. The distribution of LTC4 synthase did not overlap with that of either oxytocin or luteinizing hormone releasing hormone. Therefore, LTC4 is considered to be involved in neural functions of the brain magnocellular vasopressinergic system such as water retention. LTC4 may also be involved in extrahypothalamic vasopressinergic neural functions including the regulation of learning and memory, social recognition memory, sexual and aggressive behavior, etc.

Animals↗
PubMed2002

Transient expression of juvenile-type neurocan by reactive astrocytes in adult rat brains injured by kainate-induced seizures as well as surgical incision.

Neurocan is one of the major chondroitin sulfate proteoglycans expressed in nervous tissues. The expression of neurocan is developmentally regulated, and full-length neurocan is detected in juvenile brains but not in adult brains. In the present study, we demonstrated by western blot analysis that full-length neurocan transiently appeared in adult rat hippocampus when it was lesioned by kainate-induced seizures. Immunohistochemical studies showed that neurocan was detected mainly around the CA1 region although the seizure resulted in neuronal cell degeneration in both the CA1 and CA3 regions of the hippocampus. Double-labeling for neurocan mRNA and glial fibrillary acidic protein demonstrated that many reactive astrocytes expressed neurocan mRNA. The re-expression of full-length neurocan was also observed in the surgically injured adult rat brain. In contrast, the expression of other nervous tissue chondroitin sulfate proteoglycans, such as phosphacan and neuroglycan C, was not intensified but rather was either reduced in the kainate-lesioned hippocampus or in the surgically injured cerebral cortex. These observations indicate that induction of neurocan expression by reactive astrocytes is a common phenomenon in the repair process of adult brain injury, and therefore, it can be postulated that juvenile-type neurocan plays some roles in brain repair.

Animals↗
PubMed2002

Conserved CDR 3 region of T cell receptor BV gene in lymphocytes from bronchoalveolar lavage fluid of patients with idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is an inflammatory lung disease characterized by the accumulation of inflammatory cells and deposition of collagen, resulting in lung remodelling. High numbers of T cells are present in bronchoalveolar lavage fluid (BALF) of IPF patients, although the characteristics of these cells are yet to be determined. To elucidate the pathogenic mechanisms of IPF, we analysed the T cell receptor (TCR) of BALF lymphocytes in three patients with IPF and three healthy subjects as control. TCR repertoire of BALF lymphocytes and T cell clonality were examined by family PCR and Southern blot analysis, and single-strand conformation polymorphism (SSCP), respectively. We observed that the TCR repertoire in the lung was heterogeneous, both in the control subjects and three patients with IPF. SSCP analysis demonstrated an increase in the number of accumulated T cell clones in BALF of two of the three patients, but not in the healthy subject. Furthermore, junctional sequence analysis showed the presence of conserved amino acid motifs (ETGRSG, LAxG, QGQ, GxQP, GRxG, VAR, PGT, GTI, GGT, TGR, LxLxQ, SGQ) in the TCR-CDR 3 region of BAL lymphocytes in patients with IPF, whereas only two amino acid motifs (VTTG, GGE) were found in the control. Our findings suggest that T cells in BALF of patients with IPF expand oligoclonally in the lung, suggesting antigen stimulation of these cells.

Adult↗
PubMed2001

Regulation of neuregulin expression in the injured rat brain and cultured astrocytes.

In this report, we investigated whether reactive astrocytes produce neuregulins (glial growth factor 2/heregulin/acetylcholine receptor-inducing activity or neu differentiation factor) and its putative receptors, ErbB2 and ErbB3 tyrosine kinases, in the injured CNS in vivo. Significant immunoreactivities with anti-neuregulin, anti-ErbB2, and anti-ErbB3 antibodies were detected on astrocytes at the injured site 4 d after injury to the adult rat cerebral cortex. To elucidate the mechanisms for the upregulation of neuregulin expression in astrocytes, primary cultured astrocytes were treated with certain reagents, including forskolin, that are known to elevate the intracellular level of cAMP and induce marked morphological changes in astrocytes. Western blot analysis showed that the expression of a 52 kDa membrane-spanning form of a neuregulin protein was enhanced in cultured astrocytes after administration of forskolin. The upregulation of glial fibrillary acidic protein was also observed in astrocytes treated with forskolin. In contrast, inactivation of protein kinase C because of chronic treatment with phorbol ester 12-O-tetradecanoyl phorbol 13-acetate downregulated the expression of the 52 kDa isoform, although other splice variants with apparent molecular sizes of 65 and 60 kDa were upregulated. These results suggest that the enhancement of neuregulin expression at injured sites is induced, at least in part, by elevation in intracellular cAMP levels and/or a protein kinase C signaling pathway. The neuregulin expressed on reactive astrocytes may stimulate their proliferation and support the survival of neurons surrounding cortical brain wounds in vivo.

Animals↗
PubMed2001

Dysfunction of T cell receptor AV24AJ18+, BV11+ double-negative regulatory natural killer T cells in autoimmune diseases.

OBJECTIVE: We examined the reduction of T cell receptor (TCR) AV24+,BV11+ CD4-,CD8- (double-negative [DN]) natural killer T (NKT) cells in peripheral blood lymphocytes (PBLs) from patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), and Sjogren's syndrome (SS) to analyze why NKT cells are selectively reduced in autoimmune diseases, and to examine whether nonresponse to alpha-galactosylceramide (alpha-GalCer) is due to an abnormality in the antigen-presenting cells (APCs) or NKT cells. METHODS: Peripheral blood from patients with RA (n = 20), SLE (n = 18), SSc (n = 13), and SS (n = 17), as well as from healthy donors (n = 13) and patients with Behçet's disease (BD; n = 20), was examined by flow cytometry to determine the number of TCR AV24+,BV11+ DN T cells. PBLs from 10 RA, 10 SLE, 8 SSc, and 9 SS patients, as well as from 7 healthy subjects, were cultured in vitro with alpha-GalCer, and the number of TCR AV24+,BV11+ DN NKT cells was estimated. APCs from responder and nonresponder patients were cocultured with NKT cells from responder and nonresponder patients. RESULTS: The mean +/- SEM number of TCR AV24+,BV11+ DN NKT cells per ml of whole blood was found to be 48.8+/-10.0 in RA patients, 50.6+/-12.9 in SLE patients, 80.8+/-30.6 in SSc patients, and 40.0+/-11.7 in SS patients, while 290.0+/-69.6 and 321.2+/-103.4 NKT cells were present in healthy subjects and BD patients, respectively (P < 0.01). Three of 10 RA patients, 5 of 10 SLE patients, 4 of 8 SSc patients, and 6 of 9 SS patients (a total of 18 of 37 patients, or 48.6%) responded to alpha-GalCer, indicating that patients could be divided into two groups: alpha-GalCer responders and nonresponders. In contrast, NKT cells from all healthy subjects proliferated against alpha-GalCer. APCs from all nonresponder patients were found to function as alpha-GalCer-presenting cells, while NKT cells from nonresponders did not expand even in the presence of APCs from normal responders. CONCLUSION: These findings strongly suggest that patients with autoimmune diseases can be divided into two groups (alpha-GalCer responders and nonresponders). They also suggest that the reduced numbers of NKT cells in patients with autoimmune diseases may be due to an inadequate amount of alpha-GalCer-like natural ligands (i.e., adequate in only 48.6% of patients) for the induction of NKT cells in vivo, or to a dysfunction in the NKT cells themselves (in 51.4% of patients).

Antigen Presentation↗
PubMed2001

Analysis of T cell receptor V(beta) gene expression and clonality in bronchoalveolar fluid lymphocytes from a patient with chronic eosinophilic pneumonitis.

Chronic eosinophilic pneumonitis (CEP) is characterized by longstanding respiratory symptoms accompanied by a massive pulmonary eosinophil infiltration. T lymphocytes in bronchoalveolar lavage (BAL) from patients with chronic eosinophilic pneumonitis are considered to recognize unknown antigens. To analyze the pathogenesis of CEP, we examined the T cell receptor (TCR) repertoire and T cell clonotype of BAL lymphocytes and peripheral blood lymphocytes (PBLs) in a 66-year-old woman patient with CEP. The expression of TCR BV gene was analyzed by the family PCR method using specific primers for 20 TCR BV genes and BC gene. The clonotype of BAL and peripheral T cells was examined by the PCR-single-strand conformation polymorphism (SSCP) method. Functional sequences of some T cell clones were also carried out. A TCR repertoire of BAL T cells was heterogeneous as well as PBLs. However, SSCP analysis showed that distinct T cell clonotypes were detected in BAL T cells, TCR BV3, BV4, BV6, BV8, BV9, BV14, and BV18-positive T cell clones especially, expanded clonally in BAL from the patient. Sequencing analysis showed that GVD, LGG, RDXS, and SSG amino acid sequence motif were found in the CDR3 in lung-specific T cells. BAL-specific T cell clones accumulated in the patient with CEP. Thus, we can conclude that BAL T cells are induced by the antigen-driven stimulation and these cells might play a crucial role in the generation of CEP.

Aged↗
PubMed2001

Identification of Th2-type suppressor T cells among in vivo expanded ocular T cells in mice with experimental autoimmune uveoretinitis.

Experimental autoimmune uveoretinitis (EAU), which is a T cell mediated organ specific autoimmune disease, is induced by immunization with interphotoreceptor retinoid binding protein (IRBP) in susceptible strains of mice. It has been found that IRBP-derived peptide 518-529 (p518-529) generates Th2-type responses and inhibits IRBP-induced EAU, indicating that the p518-529 might be an epitope for suppressor T cells in IRBP-induced EAU. First, we observed that there were T cells producing the Th2 type cytokines such as IL-4 and IL-10 in late phase of EAU. Furthermore, to examine whether p518-529-reactive T cells expand in the eye during EAU, T cell receptor (TCR) of ocular T cells was compared with that of p518-529 reactive T cells in spleen from mice with EAU by PCR-single strand conformation polymorphism (PCR-SSCP) and nucleotide sequence analysis. SSCP and sequence analyses indicated that p518-529 reactive TCR BV10+ T cells bearing amino acid motif(PWG) and TCR BV13+ T cells bearing amino acid motif(PGLGGY) in their complementary-determining region 3 (CDR3) region were clonally expanding in ocular tissues on day 28 after immunization, although these T cells were not detected on day 14. These findings demonstrate that p518-529 reactive Th2-type T cells expand oligoclonally in the uveitic eyes in the late stage of EAU and may function as Th2-type suppressor T cells for improvement of the disease.

Amino Acid Motifs↗
PubMed2001

Possible roles of beta-catenin in evagination of the optic primordium in rat embryos.

The roles of beta-catenin in evagination of the optic primordium in rat embryos were studied using immunostaining. High levels of beta-catenin appeared transiently in the evaginating optic primordium. Evagination of the optic primordium was suppressed in embryos treated with LiCl. In deficient optic vesicles of these embryos, accumulation of beta-catenin was decreased. Deficient optic vesicles also showed suppression of cyclin D1 accumulation and bromodeoxyuridine incorporation, no break in the deposition of laminin and type IV collagen at the basement membrane (BM) and prevention of the change in distribution of microtubules and microfilaments. These results suggest that beta-catenin regulates cell proliferation, breakdown of BM and changes in cell shape in the evaginating optic primordium to cause optic vesicle formation.

Actin Cytoskeleton↗
PubMed2000

Genomic organization and expression pattern of mouse neuroglycan C in the cerebellar development.

Neuroglycan C (NGC) is a membrane-spanning chondroitin sulfate proteoglycan with an epidermal growth factor module that is expressed predominantly in the brain. Cloning studies with mouse NGC cDNA revealed the expression of three distinct isoforms (NGC-I, -II, and -III) in the brain and revealed that the major isoform showed 94. 3% homology with the rat counterpart. The NGC gene comprised six exons, was approximately 17 kilobases in size, and was assigned to mouse chromosome band 9F1 by fluorescence in situ hybridization. Western blot analysis demonstrated that, although NGC in the immature cerebellum existed in a proteoglycan form, most NGC in the mature cerebellum did not bear chondroitin sulfate chain(s), indicating that NGC is a typical part-time proteoglycan. Immunohistochemical studies showed that only the Purkinje cells were immunopositive in the cerebellum. In the immature Purkinje cells, NGC, probably the proteoglycan form, was immunolocalized to the soma and thick dendrites on which the climbing fibers formed synapses, not to the thin branches on which the parallel fibers formed synapses. This finding suggests the involvement of NGC in the differential adhesion and synaptogenesis of the climbing and parallel fibers with the Purkinje cell dendrites.

Alternative Splicing↗
PubMed2000

Roles of beta-catenin in inner ear development in rat embryos.

We studied the roles of beta-catenin in inner ear development in rat embryos using immunostaining and antisense experiments. High levels of beta-catenin appeared transiently in the otic cup during inner ear development. While beta-catenin accumulation was not yet observed in the thickened surface ectoderm at the otic placode, it became to be detected at the apical surface of the otic cup. Then it disappeared from the otocyst. When embryos were treated with the beta-catenin antisense oligodeoxynucleotide (ODN), accumulation of beta-catenin in the otic cup was suppressed and the beta-catenin protein level was significantly less in treated embryos than in controls. The number of cells in the otic cup in treated embryos was smaller than in control embryos. Cells that incorporated bromodeoxyuridine (BrdU) in the otic placode were fewer in number in treated embryos than in controls. In control embryos, acoustic neurons were detected by 2H3 (anti-neurofilament 165 kDa antibody) staining within the acoustic neural crest complex, while only a little staining of 2H3 was observed in the complex of the treated embryos. These results suggested that beta-catenin plays a role in cell proliferation in the otic placodes and in differentiation of acoustic neurons within the acoustic neural crest complex.

Acoustic Maculae↗
PubMed2000

Clonally accumulating T cells in the anterior chamber of Behçet disease.

PURPOSE: To clarify the nature of infiltrating T cells into the anterior chamber of a patient with Behçet disease. METHODS: Aqueous humor was obtained from a patient with ocular Behçet disease by paracentesis. RNA isolated from the cells in aqueous humor was reverse transcribed into complementary DNA. Complementary DNA encoding the variable (V) diversity (D) joining (J) (junctional) region of T-cell receptor beta chain V domain (TCR BV) chain was amplified by T-cell receptor BV family polymerase chain reaction. RESULTS: Polymerase chain reaction Southern blot analysis showed that T-cell receptor BV3, BV5, and BV7 were dominantly expressed on ocular T cells of this patient. In addition, DNA sequencing revealed that monoclonal or oligoclonal T-cell accumulation was found in T-cell receptor BV3(+), BV5(+), and BV7(+) T cells. CONCLUSION: These findings suggest that some T cells infiltrating into the anterior chamber of a patient with ocular Behçet disease expand by antigen-driven stimulation, indicating the pivotal role of T cells in the pathogenesis of ocular Behçet disease.

Adult↗
PubMed2000

A single cell analysis of Fas ligand positive T cells in rheumatoid synovial fluid.

OBJECTIVE: To investigate the function of Fas ligand (Fas-L) positive T cells in rheumatoid synovium, we analyzed the T cell receptor (TCR) CDR3 region and examined the expression of cytokines in both Fas-L+ and Fas-L- single T cells. METHODS: Synovial fluid (SF) samples were collected from 2 patients with rheumatoid arthritis. TCR BV8+ T cells were sorted into a 96 well plate at a density of one cell per well. Expression of Fas-L, interferon-gamma, interleukin 2 (IL-2), IL-4, IL-6, and IL-10 was analyzed by reverse transcription-polymerase chain reaction and Southern blot and the TCR BV8 junctional region was sequenced. RESULTS: Twenty-two of 30 TCR BV8+ T cells from Patient 1 and 20 of 43 TCR BV8+ T cells from Patient 2 were Fas-L+ T cells, while the others were Fas-L-. Junctional sequence analysis showed the presence of some conserved amino acid motifs in the CDR3 region (SRQ, GFG, SSG, SGS, LGTSGTL, TLSS) in 13 clones of Fas-L+ T cells from Patient 1, whereas no conserved amino acid motif in Fas-L-T cells was found. In Patient 2, conserved amino acid motifs (PGQ, GQG, TTWGA) in the CDR3 region were found in 6 clones of Fas-L+ T cells, while only one was found in 2 clones of Fas-L-cells. In Fas-L+ T cells, 90-93% expressed both IL-2 and IL-10 mRNA. CONCLUSION: Fas-L+ TCR BV8+ T cells revealed the conserved amino acids motif in the CDR3 region, suggesting that Fas-L+ T cells might expand by antigen stimulation and play a crucial role as Th0-type T cells in triggering autoimmunity in rheumatoid synovium.

Aged↗
PubMed1999

Intra-arterial vein bypass using a vein-loaded stent system to occlude wide-necked aneurysms: an experimental study in dogs.

We treated 13 experimental wide-necked aneurysms of lateral type produced in dog carotid arteries with a vein-loaded stent system consisting of an autologous vein graft, a vein-carrier stent, and two other self-expanding Z-shaped stents. The vein-loaded stent, made by connecting the autologous vein graft to the vein-carrier stent, was implanted in the common carotid artery to seal the aneurysm's orifice, after which two booster stents were deployed. The distal stent was placed to fix the distal end of the vein graft, and the proximal stent was placed at the proximal venous portion of the vein-loaded stent to reinforce its proximal end. In this manner an intra-arterial bypass was established across the aneurysm. Of 13 aneurysms seven were completely occluded, preserving the parent artery. The remaining six procedures resulted in parent artery occlusion because of failures in stent deployment. Angiograms performed in within 1 week six successfully treated dogs revealed the parent artery to be patent in four but thrombosed in two. Histological study of successful cases showed as smooth intima with slight endothelial hypertrophy and partially organised thrombus. The intraluminal features were also observed with a vascular endoscope at the time of treatment in four dogs and at the time of follow-up angiography in two. The appearances corresponded well to the macroscopic findings in the specimens. Our vein-loaded stent system offers complete closure of the orifice, which does not occur with conventional stent placement. The method is believed to show clinical promise for treating wide-necked aneurysms not curable by embolisation of the sac.

Aneurysm↗
PubMed1999

The role of costimulatory molecules B7-1 and B7-2 in mice with experimental autoimmune uveoretinitis.

BACKGROUND: Onset of experimental autoimmune uveoretinitis (EAU) is believed to involve a CD4-positive type 1 T helper cell (Th1) immune response, with inhibition involving a Th2 immune response. Development of Th1 and Th2 responses involves the participation of the costimulatory molecules B7-1 and B7-2, respectively. The purpose of this study was to investigate the role of B7-1 and B7-2 in the EAU model in mice. METHODS: B10.A mice were immunized with interphotoreceptor retinoid-binding protein (IRBP) and given daily intraperitoneal injections of either phosphate-buffered saline (control), mouse monoclonal antibody (mAb) to B7-1, mAb to B7-2, or mAb to both B7-1 and B7-2. Eyes were evaluated by histopathological criteria and cytokines were assayed in culture medium of IRBP-stimulated lymphocytes. Cellular immune responses were measured by cell proliferation assay under IRBP stimulation. RESULTS: Rates of EAU onset were 5/10 (50%) for control mice, 1/9 (11%) for mice treated with anti-B7-1 mAb, 5/6 (83%) for mice treated with anti-B7-2 mAb, and 2/6 (33%) for mice treated with both anti-B7-1 and anti-B7-2 mAb. Mean histopathological severity scores were 2. 4+/-0.8, 1.0+/-0, 2.6+/-1.0, and 1.0+/-0, respectively. Production of IL-5 was significantly increased in mice treated with anti-B7-1 mAb, while IFN-gamma was increased in mice treated with anti-B7-2 mAb. Spleen cell proliferation was significantly reduced in mice treated with anti-B7-1 mAb. CONCLUSIONS: These results suggest that the costimulatory molecules B7-1 and B7-2, via their influence on generating Th1 and Th2 immune responses, play an important role in the clinical outcome of EAU in mice immunized with IRBP.

Animals↗