Eiichi Okada

Genome-wide association studies identify IL23R - IL12RB2 and IL10 as Behçet's disease susceptibility loci

Behçets disease is a chronic systemic inflammatory disorder characterized by four major manifestations: recurrent ocular symptoms, oral and genital ulcers and skin lesions. We conducted a genome-wide association study in a Japanese cohort including 612 individuals with Behçets disease and 740 unaffected individuals (controls). We identified two suggestive associations on chromosomes 1p31.3 (IL23R-IL12RB2, rs12119179, P = 2.7 × 10−8) and 1q32.1 (IL10, rs1554286, P = 8.0 × 10−8). A meta-analysis of these two loci with results from additional Turkish and Korean cohorts showed genome-wide significant associations (rs1495965 in IL23R-IL12RB2, P = 1.9 × 10−11, odds ratio = 1.35; rs1800871 in IL10, P = 1.0 × 10−14, odds ratio = 1.45).

Protective immunity against influenza A virus induced by immunization with DNA plasmid containing influenza M gene.

DNA vaccination is characterized by its preferential induction of the cytotoxic T cell lymphocyte (CTL) response and is expected to be a useful means of protection against viral infection. We examined the protective effect of an expression plasmid (pME18S-M) containing M1 and M2 genes of influenza A/PR/8/34. We detected the CTL activity by introducing these plasmids into BALB/c mice by either the intramuscular or the intranasal route. The influenza-specific antibody response was also induced, although its neutralizing effect against influenza virus was not observed. From 70 to 80% protection was observed in the mice immunized with the pME18S-M plasmid followed by lethal infection with influenza viruses of the A/WSN/33 and A/PR/8/34 strains, whereas all mice without the plasmid vaccination failed to survive. This protective activity was significantly weakened when the CD8(+) cells of these immunized mice were eliminated by several injections of anti-CD8 antibody. The protective activity was also weakened when anti-CD4 antibody was injected in the early phase of DNA vaccination. These data suggest that the pME18S-M plasmid is useful as a DNA vaccine for overcoming highly mutational influenza viruses.

IL-15 expression plasmid enhances cell-mediated immunity induced by an HIV-1 DNA vaccine

Cytokines are powerful regulators of the immune response. In this study, an HIV-1 envelope DNA vaccine and interleukin 15 (IL-15) expression plasmid were intranasally administered to mice. A significant increase in the HIV-1-specific DTH response and CTL activity, and decrease in the serum IgG/IgG2a ratio was observed in the group which received DNA vaccine and IL-15 expression plasmid compared to DNA vaccination alone. Restimulated immune lymphoid cells from mice which received both agents showed enhanced production of interferon-gamma (IFN-gamma) and reduced secretion of IL-4. However, administration of DNA vaccine with IL-15 and IL-2 or IL-12 expression plasmids did not alter the effect of IL-15 expression plasmid on the DNA vaccine. These results indicate that intranasal administration of DNA vaccine and IL-15 expression plasmid is capable of enhancing the T helper type 1 (Th1) dependent HIV-1-specific cell-mediated immunity, and that the IL-15 and IL-2 or IL-12 expression plasmids may not have a synergistic effect on the immune response induced by DNA vaccine in vivo.

Genetics of Behçet disease inside and outside the MHC

Background Behçet disease (BD) is a rare, chronic, systemic, inflammatory disorder characterised by recurrent ocular, genital and skin lesions. Although its aetiology is still uncertain, an intricate interplay between the environment (eg, viruses) and the host seems to initiate and/or perpetuate the disease, although the mechanism remains speculative. Since the identification of HLA-B*5101 (and more recently of MICA) as a susceptibility locus for BD, the identification of additional genetic locus/loci, whether inside, or perhaps more importantly outside the MHC has clearly stalled. Objective To carry out a genome-wide association study (GWAS) of BD. Methods 300 Japanese patients with BD and an equal number of controls were recruited. The samples were screened using a dense panel of 23 465 microsatellites (MS) covering the entire genome. Results The six best (of a total of 147) positively associated MS with BD were identified. Of these six, two were located within the human leucocyte antigen (HLA) class I region itself. Although one of these was clearly reminiscent of the association with HLA-B, the second, not in linkage disequilibrium with the former, was in the telomeric side of the class I region and remained to be formally identified. HLA genotyping and haplotype analysis conclusively led to the deciphering of a dual, independent, contribution of two HLA alleles to the pathogenesis of BD: HLA-B*5101 and HLA-A*26. Conclusions This GWAS highlights the premier genetic susceptibility locus for BD as the major histocompatibility complex itself, wherein reside two independent loci: HLA-B and HLA-A.

Macrophage inflammatory protein-1α (MIP-1α) expression plasmid enhances DNA vaccine-induced immune response against HIV-1

CD8+ cell‐secreted CC‐chemokines, MIP‐1α, and MIP‐β have recently been identified as factors which suppress HIV. In this study we co‐inoculated MIP‐1α expression plasmid with a DNA vaccine constructed from HIV‐1 pCMV160IIIB and pcREV, and evaluated the effect of the adjuvant on HIV‐specific immune responses following intramuscular and intranasal immunization. The levels of both cytotoxic T lymphocyte (CTL) activity and DTH showed that HIV‐specific cell‐mediated immunity (CMI) was significantly enhanced by co‐inoculation of the MIP‐1α expression plasmid with the DNA vaccine compared with inoculation of the DNA vaccine alone. The HIV‐specific serum IgG1/IgG2a ratio was significantly lowered when the plasmid was co‐inoculated in both intramuscular and intranasal routes, suggesting a strong elicitation of the T helper (Th) 1‐type response. When the MIP‐1α expression plasmid was inoculated intramuscularly with the DNA vaccine, an infiltration of mononuclear cells was observed at the injection site. After intranasal administration, the level of mucosal secretory IgA antibody was markedly enhanced. These findings demonstrate that MIP‐1α expression plasmid inoculated together with DNA vaccine acts as a strong adjuvant for eliciting Th1‐derived immunity.

Age-specific prevalence of open-angle glaucoma and its relationship to refraction among more than 60,000 asymptomatic Japanese subjects

To clarify the prevalence of open-angle glaucoma (OAG) and its relationship to refraction among a Japanese population with a broad range of ages including children and adolescents, an 1-year epidemiological survey was conducted. The subjects of this study were 64,394 asymptomatic individuals who had attended the glasses and contact lens center in Yokohama, Japan from February 15, 1999 to February 14, 2000 and had been subjected to several optical examinations. The results of this study showed that the overall prevalence of OAG was 1.19% (1.14% for men, and 0.98% for women). Prevalence for children aged 6 to 14 of both sexes was approximately 0.5%. There were significant positive associations between the strength (diopter) of myopic refraction and OAG prevalence among all the examined subjects.

New susceptibility locus for high myopia is linked to the uromodulin-like 1 (UMODL1) gene region on chromosome 21q22.3

Purpose To ascertain and define the position of a potential disease susceptibility gene around D21S0083i prioritized during our previous whole genome case-control association analysis with 27158 microsatellite markers, in Japanese high-myopia patients.Methods 520 high myopic patients and 520 healthy controls were genotyped using 39 SNPs distributed around D21S0083i on chromosome 21q22.3.Results Only 1 SNP (rs2839471) of 39 SNPs was significant after correction for multiple testing (allele T: P=0.00027, Pc=0.01, OR=1.684). The SNP (rs2839471) did not reside in haplotype blocks constructed by the pair-wise linkage disequilibrium between the SNPs.Conclusions The SNP (rs2839471) is suggested to be located in the frequent recombinant region within UMODL1. Together this region might play a critical role for susceptibility to high myopia, and warrants further confirming studies and investigations as to the mechanisms by which UMODL1 may contribute to myopia.

Lysozyme penetration in group IV soft contact lenses.

Purpose. To establish proper contact lens care as a common practice by discovering the quantity and condition of protein deposition on various types of soft contact lenses. Methods. The amounts of deposition of two proteins found in tear fluid, lysozyme and albumin, on various types of contact lenses were measured. Lenses deposited with albumin and lenses deposited with lysozyme were stained with Coomassie brilliant blue (CBB). Frozen cross-sections of these lenses were examined using a microscope. Results. A considerably larger amount of lysozyme was found on group IV (U.S. Food and Drug Administration classification) contact lenses. Conversely, there were no significant differences between the four groups in the quantity of albumin found. When various lenses were stained with CBB, only the lysozyme-deposited lenses of group IV obtained a strong tint. When cross-sections of the tinted group IV contact lenses were examined, not only the surface, but also the matrix of the lens was stained. Conclusions. Results suggested that the reason group IV lenses accumulated a considerably greater amount of lysozyme than did lenses of other groups is that lysozyme accumulates not only on the surface, but also in the matrix of group IV lenses.

Factors associated with enlargement of chorioretinal atrophy after intravitreal bevacizumab for myopic choroidal neovascularization

PurposeTo determine the factors significantly associated with an enlargement of the area of a chorioretinal atrophy (ChRA) after intravitreal bevacizumab (IVB) to treat myopic choroidal neovascularization (mCNV).MethodsThe medical charts of 27 eyes with a mCNV that had received IVB were reviewed. The ophthalmic examinations included measurements of the best-corrected visual acuity, visual fields with the Humphrey 10-2 Field Analyzer, fluorescein angiography, and indocyanine green angiography. The area of the mCNV and the chorioretinal atrophy (ChRA) were measured on the FA images.ResultsEyes with an enlargement of the ChRA had significantly larger mCNVs at the baseline, a greater reduction in the size of the mCNV, a higher incidence of subretinal hemorrhage, longer duration of follow-up, received more injections of IVB, and had a greater decrease of retinal sensitivity (P ≤ 0.041). Multiple regression analyses showed that the factors most significantly associated with an enlargement of the ChRA were the CNV size at baseline, the number of IVB injections, and the duration of the follow-up period (P < 0.0001).ConclusionsOur findings showed that eyes with a larger CNV at the baseline and longer follow-up period had a greater risk of developing a ChRA like non-treatment, even if IVB treatment was performed for mCNV.

Association analysis of Toll-like receptor 7 gene polymorphisms and Behçet's disease in Japanese patients.

Action of Toll-like receptors (TLRs) is deeply associated with defense mechanisms of the innate and adaptive immune responses to microbial pathogens. There have been reports of genetic polymorphisms within the TLR7 gene being closely related to a variety of inflammatory and infectious diseases. Behçets disease (BD) is an autoinflammatory disease, and the pathogenesis has yet to be fully discovered. We investigated whether polymorphisms of Toll-like receptor 7 (TLR7) are associated with BD by analyzing the frequency of eight single nucleotide polymorphisms (SNPs) within 200 Japanese BD patients and 102 randomized controls. We genotyped nine SNPs in the TLR7 gene and assessed the allele/genotype diversity between cases and controls for all SNPs. In all eight SNPs, statistically significant differences were not observed between cases and controls.