Killer cell immunoglobulin-like receptor three domains long cytoplasmic tail 1 gene *007 may modulate disease progression of human immunodeficiency virus-1 infection in the Japanese population.

One of the KIR allele, KIR3DL1*007, was associated with the progression to acquired immunodeficiency syndrome and not with the susceptibility to HIV-1 infection in the Japanese and Indian populations, implying that KIR3DL1*007-positive NK cells might eliminate HIV-infected cells less effectively than NK cells bearing the other KIR3DL1 alleles or KIR3DS1 alleles.

CD8 T Cells Show Protection against Highly Pathogenic Simian Immunodeficiency Virus (SIV) after Vaccination with SIV Gene-Expressing BCG Prime and Vaccinia Virus/Sendai Virus Vector Boosts.

Toward development of a dual vaccine for human immunodeficiency virus type 1 (HIV-1) and tuberculosis infections, we developed a urease-deficient bacillus Calmette-Guérin (BCG) strain Tokyo172 (BCGΔurease) to enhance its immunogenicity. BCGΔurease expressing a simian immunodeficiency virus (SIV) Gag induced BCG antigen-specific CD4+ and CD8+ T cells more efficiently and more Gag-specific CD8+ T cells. We evaluated its protective efficacy against SIV infection in cynomolgus monkeys of Asian origin, shown to be as susceptible to infection with SIVmac251 as Indian rhesus macaques. Priming with recombinant BCG (rBCG) expressing SIV genes was followed by a boost with SIV gene-expressing LC16m8Δ vaccinia virus and a second boost with SIV Env-expressing Sendai virus. Eight weeks after the second boost, monkeys were repeatedly challenged with a low dose of SIVmac251 intrarectally. Two animals out of 6 vaccinees were protected, whereas all 7 control animals were infected without any early viral controls. In one vaccinated animal, which had the most potent CD8+ T cells in an in vitro suppression activity (ISA) assay of SIVmac239 replication, plasma viremia was undetectable throughout the follow-up period. Protection was confirmed by the lack of anamnestic antibody responses and detectable cell-associated provirus in various organs. Another monkey with a high ISA acquired a small amount of SIV, but it later became suppressed below the detection limit. Moreover, the ISA score correlated with SIV acquisition. On the other hand, any parameter relating anti-Env antibody was not correlated with the protection.IMPORTANCE Because both AIDS and tuberculosis are serious health threats in middle/low-income countries, development of a dual vaccine against them would be highly beneficial. To approach the goal, here we first assessed a urease-deficient bacillus Calmette-Guérin (BCG) for improvement of immunogenicity against both Mycobacterium tuberculosis and SIV. Second, we demonstrated the usefulness of Asian-origin cynomolgus monkeys for development of a preclinical AIDS vaccine by direct comparison with Indian rhesus macaques as the only validated hosts that identically mirror the outcomes of clinical trials, since the availability of Indian rhesus macaques is limited in countries other than the United States. Finally, we report the protective effect of a vaccination regimen comprising BCG, the highly attenuated vaccinia virus LC16m8Δ strain, and nontransmissible Sendai virus as safe vectors expressing SIV genes using repeated mucosal challenge with highly pathogenic SIVmac251. Identification of CD8+ T cells as a protective immunity suggests a future direction of AIDS vaccine development.

Development and evaluation of a rapid and cost-efficient NGS-based MHC class I genotyping method for macaques by using a prevalent short-read sequencer.

Rhesus macaque is one of the most widely used primate model animals for immunological research of infectious diseases including human immunodeficiency virus (HIV) infection. It is well known that major histocompatibility complex (MHC) class I genotypes affect the susceptibility and disease progression to simian immunodeficiency virus (SIV) in rhesus macaques, which is resembling to HIV in humans. It is required to convincingly determine the MHC genotypes in the immunological investigations, that is why several next-generation sequencing (NGS)-based methods have been established. In general, NGS-based genotyping methods using short amplicons are not often applied to MHC because of increasing number of alleles and inevitable ambiguity in allele detection, although there is an advantage of short read sequencing systems that are commonly used today. In this study, we developed a new high-throughput NGS-based genotyping method for MHC class I alleles in rhesus macaques and cynomolgus macaques. By using our method, 95% and 100% of alleles identified by PCR cloning-based method were detected in rhesus macaques and cynomolgus macaques, respectively, which were highly correlated with their expression levels. It was noted that the simulation of new-allele detection step using artificial alleles differing by a few nucleotide sequences from a known allele could be identified with high accuracy and that we could detect a real novel allele from a rhesus macaque sample. These findings supported that our method could be adapted for primate animal models such as macaques to reduce the cost and labor of previous NGS-based MHC genotyping.

Genetic determinants and an epistasis of LILRA3 and HLA-B*52 in Takayasu arteritis.

Takayasu arteritis (TAK) is a systemic vasculitis with severe complications that affects the aorta and its large branches. HLA-B*52 is an established susceptibility locus to TAK. To date, there are still only a limited number of reports concerning non-HLA susceptibility loci to TAK. We conducted a genome-wide association study (GWAS) and a follow-up study in a total of 633 TAK cases and 5,928 controls. A total of 510,879 SNPs were genotyped, and 5,875,450 SNPs were imputed together with HLA-B*52. Functional annotation of significant loci, enhancer enrichment, and pathway analyses were conducted. We identified four unreported significant loci, namely rs2322599, rs103294, rs17133698, and rs1713450, in PTK2B, LILRA3/LILRB2, DUSP22, and KLHL33, respectively. Two additional significant loci unreported in non-European GWAS were identified, namely HSPA6/FCGR3A and chr21q.22. We found that a single variant associated with the expression of MICB, a ligand for natural killer (NK) cell receptor, could explain the entire association with the HLA-B region. Rs2322599 is strongly associated with the expression of PTK2B Rs103294 risk allele in LILRA3/LILRB2 is known to be a tagging SNP for the deletion of LILRA3, a soluble receptor of HLA class I molecules. We found a significant epistasis effect between HLA-B*52 and rs103294 (P = 1.2 × 10-3). Enhancer enrichment analysis and pathway analysis suggested the involvement of NK cells (P = 8.8 × 10-5, enhancer enrichment). In conclusion, four unreported TAK susceptibility loci and an epistasis effect between LILRA3 and HLA-B*52 were identified. HLA and non-HLA regions suggested a critical role for NK cells in TAK.

Determination of a T cell receptor of potent CD8+ T cells against simian immunodeficiency virus infection in Burmese rhesus macaques.

Cumulative studies on human immunodeficiency virus (HIV)-infected individuals have shown association of major histocompatibility complex class I (MHC-I) polymorphisms with lower viral load and delayed AIDS progression, suggesting that HIV replication can be controlled by potent CD8+ T-cell responses. We have previously established an AIDS model of simian immunodeficiency virus (SIV) infection in Burmese rhesus macaques and found a potent CD8+ T cell targeting the Mamu-A1*065:01-restricted Gag241-249 epitope, which is located in a region corresponding to the HIV Gag240-249 TW10 epitope restricted by a protective MHC-I allele, HLA-B*57. In the present study, we determined a T cell receptor (TCR) of this Gag241-249 epitope-specific CD8+ T cell. cDNA clones encoding TCR-α and TCR-ß chains were obtained from a Gag241-249-specific CD8+ T-cell clone. Coexpression of these TCR-α and TCR-ß cDNAs resulted in reconstitution of a functional TCR specifically detected by Gag241-249 epitope-Mamu-A1*065:01 tetramer. Two of three previously-reported CD8+ T-cell escape mutations reduced binding affinity of Gag241-249 peptide to Mamu-A1*065:01 but the remaining one not. This is consistent with the data obtained by molecular modeling of the epitope-MHC-I complex and TCR. These results would contribute to understanding how viral CD8+ T-cell escape mutations are selected under structural constraint of viral proteins.

MRTF-A regulates proliferation and survival properties of pro-atherogenic macrophages.

We have previously reported that promoter polymorphism of myocardin-related transcription factor A (MRTF-A) is associated with coronary atherosclerosis. However, the contribution of MRTF-A to the development of atherosclerosis remains unknown. Macrophages are known to be important mediators of atherosclerosis. It has been demonstrated that local proliferation and survival of macrophages are atherogenic. In this study, we found that MRTF-A was highly expressed in lesional macrophages in human carotid atherosclerotic plaque. We then investigated the role of macrophagic MRTF-A in the pathogenesis of atherosclerosis. ApoE null MRTF-A transgenic mice (ApoE-/-/MRTF-Atg/+), in which human MRTF-A was specifically overexpressed in monocytes/macrophages, were established and fed with normal diet to examine the progression of atherosclerosis. We found that ApoE-/-/MRTF-Atg/+ aggravated atherosclerosis and lesional macrophages were more prominently accumulated in the aortic sinus of ApoE-/-/MRTF-Atg/+ than in that of ApoE-/- littermates. We also found that MRTF-A promoted proliferation and mitigated apoptosis of macrophages both in vitro and in vivo, and down regulated the expression of cyclin-dependent kinase inhibitors. From these findings, we conclude that MRTF-A modulates functional properties of pro-atherogenic macrophages. Our study may play a valuable role in understanding the pathological role of macrophagic MRTF-A in the progression of atherosclerosis.

In vivo virulence of MHC-adapted AIDS virus serially-passaged through MHC-mismatched hosts.

CD8+ T-cell responses exert strong suppressive pressure on HIV replication and select for viral escape mutations. Some of these major histocompatibility complex class I (MHC-I)-associated mutations result in reduction of in vitro viral replicative capacity. While these mutations can revert after viral transmission to MHC-I-disparate hosts, recent studies have suggested that these MHC-I-associated mutations accumulate in populations and make viruses less pathogenic in vitro. Here, we directly show an increase in the in vivo virulence of an MHC-I-adapted virus serially-passaged through MHC-I-mismatched hosts in a macaque AIDS model despite a reduction in in vitro viral fitness. The first passage simian immunodeficiency virus (1pSIV) obtained 1 year after SIVmac239 infection in a macaque possessing a protective MHC-I haplotype 90-120-Ia was transmitted into 90-120-Ia- macaques, whose plasma 1 year post-infection was transmitted into other 90-120-Ia- macaques to obtain the third passage SIV (3pSIV). Most of the 90-120-Ia-associated mutations selected in 1pSIV did not revert even in 3pSIV. 3pSIV showed lower in vitro viral fitness but induced persistent viremia in 90-120-Ia- macaques. Remarkably, 3pSIV infection in 90-120-Ia+ macaques resulted in significantly higher viral loads and reduced survival compared to wild-type SIVmac239. These results indicate that MHC-I-adapted SIVs serially-transmitted through MHC-I-mismatched hosts can have higher virulence in MHC-I-matched hosts despite their lower in vitro viral fitness. This study suggests that multiply-passaged HIVs could result in loss of HIV-specific CD8+ T cell responses in human populations and the in vivo pathogenic potential of these escaped viruses may be enhanced.

Diversity of ULBP5 in Old-World monkeys (Cercopithecidae) and divergence of the ULBP gene family in primates.

Non-human primates such as rhesus macaque and cynomolgus macaque are important animals for medical research. These species are classified as Old-World monkeys (Cercopithecidae), in which the immune-related genome structure is characterized by gene duplications. In the present study, we investigated polymorphisms in two genes for ULBP5 encoding ligands for NKG2D. We found 18 and 11 ULBP5.1 alleles and 11 and 13 ULBP5.2 alleles in rhesus macaques and cynomolgus macaques, respectively. In addition, phylogenetic analyses revealed that ULBP5.2 diverged from a branch of ULBP5.1. These data suggested that human ULBP genes diverged from an ancestral gene of ULBP2-ULBP5 and that ULBP6/RAET1L, specifically identified in human, diverged from an ancestral ULBP2 by a recent gene duplication after the diversification of homininae (human and other higher great apes), which were consistent with the findings in our previous analysis of ULBP2 genes in rhesus and cynomolgus macaques.

Diversity of MHC class I alleles in Spheniscus humboldti.

The major histocompatibility complex locus (MHC) is a gene region related to immune response and exhibits a remarkably great diversity. We deduced that polymorphisms in MHC genes would help to solve several issues on penguins, including classification, phylogenetic relationship, and conservation. This study aimed to elucidate the structure and diversity of the so far unknown MHC class I gene in a penguin species. The structure of an MHC class I gene from the Humboldt penguin (Spheniscus humboldti) was determined by using an inverse PCR method. We designed PCR primers to directly determine nucleotide sequences of PCR products from the MHC class I gene and to obtain recombinant clones for investigating the diversity of the MHC class I gene in Humboldt penguins. A total of 24 MHC class I allele sequences were obtained from 40 individuals. Polymorphisms were mainly found in exons 2 and 3, as expected from the nature of MHC class I genes in vertebrate species including birds and mammals. Phylogenetic analyses of MHC class I alleles have revealed that the Humboldt penguin is closely related to the Red Knot (Calidris canutus) belonging to Charadriiformes.

Biphasic CD8+ T-Cell Defense in Simian Immunodeficiency Virus Control by Acute-Phase Passive Neutralizing Antibody Immunization.

UNLABELLED: Identifying human immunodeficiency virus type 1 (HIV-1) control mechanisms by neutralizing antibodies (NAbs) is critical for anti-HIV-1 strategies. Recent in vivo studies on animals infected with simian immunodeficiency virus (SIV) and related viruses have shown the efficacy of postinfection NAb passive immunization for viremia reduction, and one suggested mechanism is its occurrence through modulation of cellular immune responses. Here, we describe SIV control in macaques showing biphasic CD8(+) cytotoxic T lymphocyte (CTL) responses following acute-phase NAb passive immunization. Analysis of four SIVmac239-infected rhesus macaque pairs matched with major histocompatibility complex class I haplotypes found that counterparts receiving day 7 anti-SIV polyclonal NAb infusion all suppressed viremia for up to 2 years without accumulating viral CTL escape mutations. In the first phase of primary viremia control attainment, CD8(+) cells had high capacities to suppress SIVs carrying CTL escape mutations. Conversely, in the second, sustained phase of SIV control, CTL responses converged on a pattern of immunodominant CTL preservation. During this sustained phase of viral control, SIV epitope-specific CTLs showed retention of phosphorylated extracellular signal-related kinase (ERK)(hi)/phosphorylated AMP-activated protein kinase (AMPK)(lo) subpopulations, implying their correlation with SIV control. The results suggest that virus-specific CTLs functionally boosted by acute-phase NAbs may drive robust AIDS virus control. IMPORTANCE: In early HIV infection, NAb responses are lacking and CTL responses are insufficient, which leads to viral persistence. Hence, it is important to identify immune responses that can successfully control such HIV replication. Here, we show that monkeys receiving NAb passive immunization in early SIV infection strictly control viral replication for years. Passive infusion of NAbs with CTL cross-priming capacity resulted in induction of functionally boosted early CTL responses showing enhanced suppression of CTL escape mutant virus replication. Accordingly, the NAb-infused animals did not show accumulation of viral CTL escape mutations during sustained SIV control, and immunodominant CTL responses were preserved. This early functional augmentation of CTLs by NAbs provides key insights into the design of lasting and viral escape mutation-free protective immunity against HIV-1 infection.

Broadening of Virus-Specific CD8+ T-Cell Responses Is Indicative of Residual Viral Replication in Aviremic SIV Controllers.

Control of HIV replication is a rare immunological event, providing clues to understand the viral control mechanism. CD8+ T-cell responses are crucial for virus control, but it is unclear whether lasting HIV containment can be achieved after establishment of infection. Here, we describe lasting SIV containment in a macaque AIDS model. Analysis of ten rhesus macaques that controlled viremia for 2 years post-infection found accumulation of proviral gag and nef CD8+ T-cell escape mutations in four of them. These four controllers mounted CD8+ T cells targeting Gag, Nef, and other viral proteins at 4 months, suggesting that broadening of CD8+ T-cell targets can be an indicator of the beginning of viral control failure. The remaining six aviremic SIV controllers, however, harbored proviruses without mutations and showed no or little broadening of their CD8+ T-cell responses in the chronic phase. Indeed, three of the latter six exhibiting no change in CD8+ T-cell targets showed gradual decreases in SIV-specific CD8+ T-cell frequencies, implying a concomitant reduction in viral replication. Thus, stability of the breadth of virus-specific CD8+ T-cell responses may represent a status of lasting HIV containment by CD8+ T cells.

Two susceptibility loci to Takayasu arteritis reveal a synergistic role of the IL12B and HLA-B regions in a Japanese population.

Takayasu arteritis (TAK) is an autoimmune systemic vasculitis of unknown etiology. Although previous studies have revealed that HLA-B*52:01 has an effect on TAK susceptibility, no other genetic determinants have been established so far. Here, we performed genome scanning of 167 TAK cases and 663 healthy controls via Illumina Infinium Human Exome BeadChip arrays, followed by a replication study consisting of 212 TAK cases and 1,322 controls. As a result, we found that the IL12B region on chromosome 5 (rs6871626, overall p = 1.7 × 10(-13), OR = 1.75, 95% CI 1.42-2.16) and the MLX region on chromosome 17 (rs665268, overall p = 5.2 × 10(-7), OR = 1.50, 95% CI 1.28-1.76) as well as the HLA-B region (rs9263739, a proxy of HLA-B*52:01, overall p = 2.8 × 10(-21), OR = 2.44, 95% CI 2.03-2.93) exhibited significant associations. A significant synergistic effect of rs6871626 and rs9263739 was found with a relative excess risk of 3.45, attributable proportion of 0.58, and synergy index of 3.24 (p ≤ 0.00028) in addition to a suggestive synergistic effect between rs665268 and rs926379 (p ≤ 0.027). We also found that rs6871626 showed a significant association with clinical manifestations of TAK, including increased risk and severity of aortic regurgitation, a representative severe complication of TAK. Detection of these susceptibility loci will provide new insights to the basic mechanisms of TAK pathogenesis. Our findings indicate that IL12B plays a fundamental role on the pathophysiology of TAK in combination with HLA-B(∗)52:01 and that common autoimmune mechanisms underlie the pathology of TAK and other autoimmune disorders such as psoriasis and inflammatory bowel diseases in which IL12B is involved as a genetic predisposing factor.

APOBEC3H polymorphisms and susceptibility to HIV-1 infection in an Indian population.

Human APOBEC3H (A3H) is a member of APOBEC cytidine deaminase family intensively constraining the HIV-1 replication. A3H is known to be polymorphic with different protein stability and anti-HIV-1 activity in vitro. We recently reported that A3H haplotypes composed of two functional polymorphisms, rs139292 (N15del) and rs139297 (G105R), were associated with the susceptibility to HIV-1 infection in Japanese. To confirm the association of A3H and HIV-1 infection in another ethnic group, a total of 241 HIV-1-infected Indian individuals and ethnic-matched 286 healthy controls were analyzed for the A3H polymorphisms. The frequency of 15del allele was high in the HIV-1-infected subjects as compared with the controls (0.477 vs 0.402, odds ratio (OR)=1.36, P=0.014). Haplotype analysis showed that the frequencies of 15del-105R was high (0.475 vs 0.400, OR=1.36, permutation P=0.037) in the HIV-1-infected subjects, confirming the association of A3H polymorphisms with the susceptibility to HIV-1 infection.

APOBEC3H polymorphisms associated with the susceptibility to HIV-1 infection and AIDS progression in Japanese.

Human APOBEC3H (A3H) is a member of APOBEC3 cytidine deaminase family that potently restricts HIV-1 replication. Because A3H is genetically divergent with different intracellular stability and anti-HIV-1 activity in vitro, we investigated a possible association of A3H with susceptibility to HIV-1 infection and disease progression in Japanese populations. A total of 191 HIV-1-infected individuals (HIV group), 93 long-term non-progressors to AIDS (LTNP group) and 421 healthy controls were genotyped for two functional APOBEC3H polymorphisms, rs139292 and rs139297. As compared with the controls, minor allele frequency (MAF) for rs139292 was high in the HIV group (MAF in cases vs. controls; 0.322 vs. 0.263, odds ratio (OR) = 1.33, 95% confidence interval (95% CI) = 1.02-1.74, p = 0.035) and low in the LTNP group (0.161 vs. 0.263, OR = 0.54, 95% CI = 0.36-0.82, p = 0.004, pc = 0.007), whereas the MAF for rs139297 was high in the HIV group (0.367 vs. 0.298, OR = 1.36, 95% CI = 1.07-1.76, p = 0.017, pc = 0.035). In addition, haplotype analyses revealed that the frequencies of A3H-hapC and -hapA were high (0.322 vs. 0.262, OR = 1.33, 95% CI = 1.02-1.74, p = 0.003) and low (0.634 vs. 0.697, OR = 0.75, 95 % CI = 0.58-0.97, p = 0.002), respectively, in the HIV group, whereas the frequencies of A3H-hapC and -hapB were low (0.161 vs. 0.262, OR = 0.54, 95% CI = 0.36-0.82, p = 0.00003) and high (0.097 vs. 0.040, OR = 2.55, 95% CI = 1.40-4.62, p = 0.000008), respectively, in the LTNP group, as compared with those in the controls. These observations suggest that the A3H with low anti-HIV-1 activity, A3H-hapC, is associated with the susceptibility to HIV-1 infection, whereas the A3H producing a stable protein, A3H-hapB, may confer a low risk of disease progression to AIDS.

Control of simian immunodeficiency virus replication by vaccine-induced Gag- and Vif-specific CD8+ T cells.

For development of an effective T cell-based AIDS vaccine, it is critical to define the antigens that elicit the most potent responses. Recent studies have suggested that Gag-specific and possibly Vif/Nef-specific CD8(+) T cells can be important in control of the AIDS virus. Here, we tested whether induction of these CD8(+) T cells by prophylactic vaccination can result in control of simian immunodeficiency virus (SIV) replication in Burmese rhesus macaques sharing the major histocompatibility complex class I (MHC-I) haplotype 90-010-Ie associated with dominant Nef-specific CD8(+) T-cell responses. In the first group vaccinated with Gag-expressing vectors (n = 5 animals), three animals that showed efficient Gag-specific CD8(+) T-cell responses in the acute phase postchallenge controlled SIV replication. In the second group vaccinated with Vif- and Nef-expressing vectors (n = 6 animals), three animals that elicited Vif-specific CD8(+) T-cell responses in the acute phase showed SIV control, whereas the remaining three with Nef-specific but not Vif-specific CD8(+) T-cell responses failed to control SIV replication. Analysis of 18 animals, consisting of seven unvaccinated noncontrollers and the 11 vaccinees described above, revealed that the sum of Gag- and Vif-specific CD8(+) T-cell frequencies in the acute phase was inversely correlated with plasma viral loads in the chronic phase. Our results suggest that replication of the AIDS virus can be controlled by vaccine-induced subdominant Gag/Vif epitope-specific CD8(+) T cells, providing a rationale for the induction of Gag- and/or Vif-specific CD8(+) T-cell responses by prophylactic AIDS vaccines.

Screening of sarcomere gene mutations in young athletes with abnormal findings in electrocardiography: identification of a MYH7 mutation and MYBPC3 mutations.

There is an overlap between the physiological cardiac remodeling associated with training in athletes, the so-called athlete's heart, and mild forms of hypertrophic cardiomyopathy (HCM), the most common hereditary cardiac disease. HCM is often accompanied by unfavorable outcomes including a sudden cardiac death in the adolescents. Because one of the initial signs of HCM is abnormality in electrocardiogram (ECG), athletes may need to monitor for ECG findings to prevent any unfavorable outcomes. HCM is caused by mutations in genes for sarcomere proteins, but there is no report on the systematic screening of gene mutations in athletes. One hundred and two genetically unrelated young Japanese athletes with abnormal ECG findings were the subjects for the analysis of four sarcomere genes, MYH7, MYBPC3, TNNT2 and TNNI3. We found that 5 out of 102 (4.9%) athletes carried mutations: a heterozygous MYH7 Glu935Lys mutation, a heterozygous MYBPC3 Arg160Trp mutation and another heterozygous MYBPC3 Thr1046Met mutation, all of which had been reported as HCM-associated mutations, in 1, 2 and 2 subjects, respectively. This is the first study of systematic screening of sarcomere gene mutations in a cohort of athletes with abnormal ECG, demonstrating the presence of sarcomere gene mutations in the athlete's heart.

A DFNA5 mutation identified in Japanese families with autosomal dominant hereditary hearing loss.

Mutations in DFNA5 lead to autosomal dominant nonsyndromic hereditary hearing loss (NSHHL). To date, four different mutations in DFNA5 have been reported to cause hearing loss. A 3 bp deletion mutation (c.991-15_991-13del) was identified in Chinese and Korean families with autosomal dominant NSHHL, which suggested that the 3 bp deletion mutation was derived from a single origin. In the present study, we performed genetic screening of mutations in the interval between intron 6 and exon 9 of DFNA5 in 65 Japanese patients with autosomal dominant NSHHL and identified the c.991-15_991-13del mutation in two patients. Furthermore, we compared the DFNA5-linked haplotypes consisting of intragenic SNPs between the reported Chinese and Korean families and found that the Japanese patients showed a shared region spanning 41,874 bp. This is the first report of DFNA5 mutations in Japanese patients with autosomal dominant NSHHL, supporting the suggestion that the 3 bp deletion mutation occurred in their ancestors.

Divergence and diversity of ULBP2 genes in rhesus and cynomolgus macaques.

Non-human primates such as rhesus macaque and cynomolgus macaque are important animals for medical research fields and they are classified as Old World monkey, in which genome structure is characterized by gene duplications. In the present study, we investigated polymorphisms in two genes for ULBP2 molecules that are ligands for NKG2D. A total of 15 and 11 ULBP2.1 alleles and 11 and 10 ULBP2.2 alleles were identified in rhesus macaques and cynomolgus macaques, respectively. Nucleotide sequences of exons for extra cellular domain were highly polymorphic and more than 70 % were non-synonymous variations in both ULBP2.1 and ULBP2.2. In addition, phylogenetic analyses revealed that the ULBP2.2 was diverged from a branch of ULBP2.1 along with ULBP2s of higher primates. Moreover, when 3D structural models were constructed for the rhesus ULBP2 molecules, residues at presumed contact sites with NKG2D were polymorphic in ULBP2.1 and ULBP2.2 in the rhesus macaque and cynomolgus macaque, respectively. These observations suggest that amino acid replacements at the interaction sites with NKG2D might shape a specific nature of ULBP2 molecules in the Old World monkeys.

Identification of SIV Nef CD8(+) T cell epitopes restricted by a MHC class I haplotype associated with lower viral loads in a macaque AIDS model.

Virus-specific CD8(+) T-cell responses are crucial for the control of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) replication. Multiple studies on HIV-infected individuals and SIV-infected macaques have indicated association of several major histocompatibility complex class I (MHC-I) genotypes with lower viral loads and delayed AIDS progression. Understanding of the viral control mechanism associated with these MHC-I genotypes would contribute to the development of intervention strategy for HIV control. We have previously reported a rhesus MHC-I haplotype, 90-120-Ia, associated with lower viral loads after SIVmac239 infection. Gag206-216 and Gag241-249 epitope-specific CD8(+) T-cell responses have been shown to play a central role in the reduction of viral loads, whereas the effect of Nef-specific CD8(+) T-cell responses induced in all the 90-120-Ia(+) macaques on SIV replication remains unknown. Here, we identified three CD8(+) T-cell epitopes, Nef9-19, Nef89-97, and Nef193-203, associated with 90-120-Ia. Nef9-19 and Nef193-203 epitope-specific CD8(+) T-cell responses frequently selected for mutations resulting in viral escape from recognition by these CD8(+) T cells, indicating that these CD8(+) T cells exert strong suppressive pressure on SIV replication. Results would be useful for elucidation of the viral control mechanism associated with 90-120-Ia.

Impact of vaccination on cytotoxic T lymphocyte immunodominance and cooperation against simian immunodeficiency virus replication in rhesus macaques.

Cytotoxic T lymphocyte (CTL) responses play a central role in viral suppression in human immunodeficiency virus (HIV) infections. Prophylactic vaccination resulting in effective CTL responses after viral exposure would contribute to HIV control. It is important to know how CTL memory induction by vaccination affects postexposure CTL responses. We previously showed vaccine-based control of a simian immunodeficiency virus (SIV) challenge in a group of Burmese rhesus macaques sharing a major histocompatibility complex class I haplotype. Gag(206-216) and Gag(241-249) epitope-specific CTL responses were responsible for this control. In the present study, we show the impact of individual epitope-specific CTL induction by prophylactic vaccination on postexposure CTL responses. In the acute phase after SIV challenge, dominant Gag(206-216)-specific CTL responses with delayed, naive-derived Gag(241-249)-specific CTL induction were observed in Gag(206-216) epitope-vaccinated animals with prophylactic induction of single Gag(206-216) epitope-specific CTL memory, and vice versa in Gag(241-249) epitope-vaccinated animals with single Gag(241-249) epitope-specific CTL induction. Animals with Gag(206-216)-specific CTL induction by vaccination selected for a Gag(206-216)-specific CTL escape mutation by week 5 and showed significantly less decline of plasma viral loads from week 3 to week 5 than in Gag(241-249) epitope-vaccinated animals without escape mutations. Our results present evidence indicating significant influence of prophylactic vaccination on postexposure CTL immunodominance and cooperation of vaccine antigen-specific and non-vaccine antigen-specific CTL responses, which affects virus control. These findings provide great insights into antigen design for CTL-inducing AIDS vaccines.