HLA-A*24 Increases the Risk of HTLV-1-Associated Myelopathy despite Reducing HTLV-1 Proviral Load.

Increased human T-cell leukemia virus type 1 (HTLV-1) proviral load (PVL) is a significant risk factor for HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). There is controversy surrounding whether HTLV-1-specific cytotoxic T lymphocytes (CTLs) are beneficial or harmful to HAM/TSP patients. Recently, HTLV-1 Tax 301-309 has been identified as an immunodominant epitope restricted to HLA-A*2402. We investigated whether HLA-A*24 reduces HTLV-1 PVL and the risk of HAM/TSP using blood samples from 152 HAM/TSP patients and 155 asymptomatic HTLV-1 carriers. The allele frequency of HLA-A*24 was higher in HAM/TSP patients than in asymptomatic HTLV-1 carriers (72.4% vs. 58.7%, odds ratio 1.84), and HLA-A*24-positive patients showed a 42% reduction in HTLV-1 PVL compared to negative patients. Furthermore, the PVL negatively correlated with the frequency of Tax 301-309-specific CTLs. These findings are opposite to the effects of HLA-A*02, which reduces HTLV-1 PVL and the risk of HAM/TSP. Therefore, we compared the functions of CTLs specific to Tax 11-19 or Tax 301-309, which are immunodominant epitopes restricted to HLA-A*0201 or HLA-A*2402, respectively. The maximum responses of these CTLs were not different in the production of IFN-γ and MIP-1ß or in the expression of CD107a-a marker for the degranulation of cytotoxic molecules. However, Tax 301-309-specific CTLs demonstrated 50-fold higher T-cell avidity than Tax 11-19-specific CTLs, suggesting better antigen recognition at low expression levels of the antigens. These findings suggest that HLA-A*24, which induces sensitive HTLV-1-specific CTLs, increases the risk of HAM/TSP despite reducing HTLV-1 PVL.

The novel HLA-A*24:627 allele, identified by Sanger dideoxy nucleotide sequencing in a Chinese individual.

The HLA-A*24:627 allele differs from HLA-A*24:02:01:01 by one nucleotide substitution in codon 172 in exon 2.

Characterization of the novel HLA-A*24:02:154 allele in a Chinese individual.

HLA-A*24:02:154 has one nucleotide change compared with HLA-A*24:02:01:01 in codon 113 of exon 3 (TAC > TAT).

The novel HLA-A*24:02:159 allele, identified by Sanger dideoxy nucleotide sequencing in a Chinese individual.

HLA-A*24:02:159 differs from HLA-A*24:02:01:01 by one nucleotide in exon 3.

Carbamazepine-modified HLA-A*24:02-bound peptidome: Implication of CORO1A in skin rash.

BACKGROUND: Previous studies have demonstrated that human leukocyte antigen (HLA)-A*24:02 is a common genetic risk factor for antiepileptic drug-induced skin rash, while HLA-B*15:02 is a specific risk factor for carbamazepine (CBZ)-induced Stevens Johnson syndrome and toxin epidermal necrolysis. The HLA-B*15:02 allele can alter the repertoire of endogenous peptides to trigger CBZ-induced hypersensitivity. However, it is uncertain whether HLA-A*24:02 could produce alterations in the peptide repertoire during treatment with antiepileptic drugs. METHODS: We generated stable HMy2.C1R cells expressing HLA-A*24:02 and HLA-B*15:02, clarified into 4 groups according to with or without CBZ treatment. We employed LC/MSto detect the HLA-bound peptides in 4 groups. Furthermore, we conducted in silico analysis to seek th differential expressed genes (DEGs) associated with HLA-A*24:02 and HLA-B*15:02. Finally, we verify the DEGs via qRT-PCR and Western blotting. RESULTS: A total of 134 peptides were identified from the four groups, mainly comprising<15 mer peptides. In CBZ-treated groups, 29 and 30 peptides showed significantly increased respectively in HLA-A*24:02 and HLA-B*15:02 positive cells comprising Lysine in PΩ, but the sources of these lysine peptides are different. Three peptides were exclusively detected in the HLA-A*24:02 positive cells treated with CBZ, of which 'SRQVVRSSK' was derived from the immune associated protein coronin 1A (CORO1A). CORO1A and its mRNA were significantly expressed in HLA-A*24:02 positive cells treated with CBZ. Additionally, this significantly high expression was identified in HLA-A*24:02 positive cells that were treated with lamotrigine (LTG). Nonetheless, CORO1A were not decreased in HLA-B*15:02 positive cells with or without CBZ or LTG treatment. CONCLUSIONS: These findings confirmed that the alteration in the endogenous peptidome was a general mechanism of HLA-linked skin rashes and suggests that CORO1A is involved in HLA-A*24:02-associated skin rash.

Identification of HLA-A*24:02-Restricted CTL Candidate Epitopes Derived from the Nonstructural Polyprotein 1a of SARS-CoV-2 and Analysis of Their Conservation Using the Mutation Database of SARS-CoV-2 Variants.

COVID-19 vaccines are currently being administered worldwide and playing a critical role in controlling the pandemic. They have been designed to elicit neutralizing antibodies against Spike protein of the original SARS-CoV-2, and hence they are less effective against SARS-CoV-2 variants with mutated Spike than the original virus. It is possible that novel variants with abilities of enhanced transmissibility and/or immunoevasion will appear in the near future and perfectly escape from vaccine-elicited immunity. Therefore, the current vaccines may need to be improved to compensate for the viral evolution. For this purpose, it may be beneficial to take advantage of CD8+ cytotoxic T lymphocytes (CTLs). Several lines of evidence suggest the contribution of CTLs on the viral control in COVID-19, and CTLs target a wide range of proteins involving comparatively conserved nonstructural proteins. Here, we identified 22 HLA-A*24:02-restricted CTL candidate epitopes derived from the nonstructural polyprotein 1a (pp1a) of SARS-CoV-2 using computational algorithms, HLA-A*24:02 transgenic mice and the peptide-encapsulated liposomes. We focused on pp1a and HLA-A*24:02 because pp1a is relatively conserved and HLA-A*24:02 is predominant in East Asians such as Japanese. The conservation analysis revealed that the amino acid sequences of 7 out of the 22 epitopes were hardly affected by a number of mutations in the Sequence Read Archive database of SARS-CoV-2 variants. The information of such conserved epitopes might be useful for designing the next-generation COVID-19 vaccine that is universally effective against any SARS-CoV-2 variants by the induction of both anti-Spike neutralizing antibodies and CTLs specific for conserved epitopes. IMPORTANCE COVID-19 vaccines have been designed to elicit neutralizing antibodies against the Spike protein of the original SARS-CoV-2, and hence they are less effective against variants. It is possible that novel variants will appear and escape from vaccine-elicited immunity. Therefore, the current vaccines may need to be improved to compensate for the viral evolution. For this purpose, it may be beneficial to take advantage of CD8+ cytotoxic T lymphocytes (CTLs). Here, we identified 22 HLA-A*24:02-restricted CTL candidate epitopes derived from the nonstructural polyprotein 1a (pp1a) of SARS-CoV-2. We focused on pp1a and HLA-A*24:02 because pp1a is conserved and HLA-A*24:02 is predominant in East Asians. The conservation analysis revealed that the amino acid sequences of 7 out of the 22 epitopes were hardly affected by mutations in the database of SARS-CoV-2 variants. The information might be useful for designing the next-generation COVID-19 vaccine that is universally effective against any variants.

Collaboration of a Detrimental HLA-B*35:01 Allele with HLA-A*24:02 in Coevolution of HIV-1 with T Cells Leading to Poorer Clinical Outcomes.

Although mutant-specific T cells are elicited in some individuals infected with HIV-1 mutant viruses, the detailed characteristics of these T cells remain unknown. A recent study showed that the accumulation of strains expressing Nef135F, which were selected by HLA-A*24:02-restricted T cells, was associated with poor outcomes in individuals with the detrimental HLA-B*35:01 allele and that HLA-B*35:01-restricted NefYF9 (Nef135-143)-specific T cells failed to recognize target cells infected with Nef135F mutant viruses. Here, we investigated HLA-B*35:01-restricted T cells specific for the NefFF9 epitope incorporating the Nef135F mutation. Longitudinal T-cell receptor (TCR) clonotype analysis demonstrated that 3 types of HLA-B*35:01-restricted T cells (wild-type [WT] specific, mutant specific, and cross-reactive) with different T cell repertoires were elicited during the clinical course. HLA-B*35:01+ individuals possessing wild-type-specific T cells had a significantly lower plasma viral load (pVL) than those with mutant-specific and/or cross-reactive T cells, even though the latter T cells effectively recognized the mutant virus-infected cells. These results suggest that mutant-specific and cross-reactive T cells could only partially suppress HIV-1 replication in vivo. An ex vivo analysis of the T cells showed higher expression of PD-1 on cross-reactive T cells and lower expression of CD160/2B4 on the mutant-specific T cells than other T cells, implying that these inhibitory and stimulatory molecules are key to the reduced function of these T cells. In the present study, we demonstrate that mutant-specific and cross-reactive T cells do not contribute to the suppression of HIV-1 replication in HIV-1-infected individuals, even though they have the capacity to recognize mutant virus-infected cells. Thus, the collaboration of HLA-A*24:02 with the detrimental allele HLA-B*35:01 resulted in the coevolution of HIV-1 alongside virus-specific T cells, leading to poorer clinical outcomes. IMPORTANCE HIV-1 escape mutations are selected under pressure from HIV-1-specific CD8+ T cells. Accumulation of these mutations in circulating viruses impairs the control of HIV-1 by HIV-1-specific T cells. Although it is known that HIV-1-specific T cells recognizing mutant virus were elicited in some individuals infected with a mutant virus, the role of these T cells remains unclear. Accumulation of phenylalanine at HIV-1 Nef135 (Nef135F), which is selected by HLA-A*24:02-restricted T cells, led to poor clinical outcome in individuals carrying the detrimental HLA-B*35:01 allele. In the present study, we found that HLA-B*35:01-restricted mutant-specific and cross-reactive T cells were elicited in HLA-B*35:01+ individuals infected with the Nef135F mutant virus. These T cells could not effectively suppress HIV-1 replication in vivo even though they could recognize mutant virus-infected cells in vitro. Mutant-specific and cross-reactive T cells expressed lower levels of stimulatory molecules and higher levels of inhibitory molecules, respectively, suggesting a potential mechanism whereby these T cells fail to suppress HIV-1 replication in HIV-1-infected individuals.

CD8+ T cell landscape in Indigenous and non-Indigenous people restricted by influenza mortality-associated HLA-A*24:02 allomorph.

Indigenous people worldwide are at high risk of developing severe influenza disease. HLA-A*24:02 allele, highly prevalent in Indigenous populations, is associated with influenza-induced mortality, although the basis for this association is unclear. Here, we define CD8+ T-cell immune landscapes against influenza A (IAV) and B (IBV) viruses in HLA-A*24:02-expressing Indigenous and non-Indigenous individuals, human tissues, influenza-infected patients and HLA-A*24:02-transgenic mice. We identify immunodominant protective CD8+ T-cell epitopes, one towards IAV and six towards IBV, with A24/PB2550-558-specific CD8+ T cells being cross-reactive between IAV and IBV. Memory CD8+ T cells towards these specificities are present in blood (CD27+CD45RA- phenotype) and tissues (CD103+CD69+ phenotype) of healthy individuals, and effector CD27-CD45RA-PD-1+CD38+CD8+ T cells in IAV/IBV patients. Our data show influenza-specific CD8+ T-cell responses in Indigenous Australians, and advocate for T-cell-mediated vaccines that target and boost the breadth of IAV/IBV-specific CD8+ T cells to protect high-risk HLA-A*24:02-expressing Indigenous and non-Indigenous populations from severe influenza disease.

Genomic full-length sequence of the HLA-A*24:02:61 allele, identified by full-length group-specific sequencing.

Genomic full-length sequence of HLA-A*24:02:61 was identified by group-specific sequencing in a Chinese individual.

HLA-A∗24:02 associated with lamotrigine-induced cutaneous adverse drug reactions: A systematic review and meta-analysis.

BACKGROUND: Several studies demonstrated a connection between human leukocyte antigen (HLA)-B∗1502 and lamotrigine (LTG)-induced cutaneous adverse drug reactions (cADRs). The correlation between the HLA-A∗24:02 and LTG-cADRs remains controversial. To examine the associations between HLA-A∗24:02 and LTG-cADRs, we conducted a systematic review and meta-analysis. METHODS: We performed a comprehensive search of the literature in several electronic database systems including Cochrane Library, EMBASE and PubMed from inception to January 2020. Review Manager was used to compare the frequencies of HLA-A∗24:02 carriers between the subgroups. RESULTS: A total of 5 studies were eligible, including 197 LTD-cADRs, 396 LTD-tolerant controls, and 2068 population controls. Compared with the LTG-tolerant controls, there was a statistically significant association between the HLA-A∗24:02 allele and LTG-induced cADRs (odds ratios: 1.94, 95% confidence intervals 1.06-3.54; P = .03). Compared with the general population, the relationship between the HLA-A∗24:02 genotype and LTG-induced cADRs was statistically significant (summary odds ratios: 2.12, 95% confidence intervals 1.04-4.30; P = .04). CONCLUSIONS: HLA-A∗24:02 may be a risk factor for LTG-cADRs.

Association between HLA-A gene polymorphism and early-onset preeclampsia in Chinese pregnant women early-onset.

BACKGROUND: Preeclampsia is an idiopathic disease during pregnancy. This study explores the correlation between HLA-A polymorphism and the onset of preeclampsia. METHODS: The Illumina HiSeq2500 sequencing platform was used to genotyping HLA-A allele in venous blood DNA of 50 preeclampsia pregnant women and 48 normal pregnant women and umbilical cord blood DNA of their children of Han nationality in China. The frequencies and distributions of alleles and genotypes among the mothers and their children were compared between the two groups. The differences of frequencies and distributions of genotypes were compared between the two groups according to the mothers' genotype compatibility. RESULTS: Twenty HLA-A alleles were detected in preeclampsia pregnant women and normal pregnant women; 21 HLA-A alleles were found in preeclampsia group fetuses and 22 HLA-A alleles in control group fetuses. There was no statistical difference in the HLA-A genes' frequency between the two groups of pregnant women and their fetuses. When the sharing antigen was 1, the number of maternal-fetal pairs in the preeclampsia group was more than that in the control group; the difference was statistically significant (P < 0.05). The frequency of neither mother nor fetus carrying the HLA-A * 24: 02 gene in the preeclampsia group was significantly lower than that in the control group (P < 0.05). HLA-A gene homozygosity in fetuses of early-onset preeclampsia group was substantially higher than that of the control group (P = 0.0148); there is no significant difference in pregnant women's genes homozygosity between early-onset preeclampsia group and the control group. CONCLUSIONS: HLA-A * 24: 02 may be a susceptibility gene for early preeclampsia.

TAS0314, a novel multi-epitope long peptide vaccine, showed synergistic antitumor immunity with PD-1/PD-L1 blockade in HLA-A*2402 mice.

Cancer peptide vaccines are a promising cancer immunotherapy that can induce cancer-specific cytotoxic T lymphocytes (CTLs) in tumors. However, recent clinical trials of cancer vaccines have revealed that the efficacy of the vaccines is limited. Targeting single antigens and vaccination with short peptides are partly the cause of the poor clinical outcomes. We synthesized a novel multi-epitope long peptide, TAS0314, which induced multiple epitope-specific CTLs in HLA knock-in mice. It also showed superior epitope-specific CTL induction and antitumor activity. We also established a combination treatment model of vaccination with PD-1/PD-L1 blockade in HLA-A*2402 knock-in mice, and it showed a synergistic antitumor effect with TAS0314. Thus, our data indicated that TAS0314 treatment, especially in combination with PD-1/PD-L1 blockade, is a promising therapeutic candidate for cancer immunotherapy.

Development of an artificial antibody specific for HLA/peptide complex derived from cancer stem-like cell/cancer-initiating cell antigen DNAJB8.

BACKGROUND: Peptide-vaccination therapy targeting tumour-associated antigens can elicit immune responses, but cannot be used to eliminate large tumour burden. In this study, we developed a therapeutic single-chain variable-fragment (scFv) antibody that recognises the cancer stem-like cell/cancer-initiating cell (CSC/CIC) antigen, DNAJB8. METHODS: We screened scFv clones reacting with HLA-A24:20/DNAJB8-derived peptide (DNAJB8_143) complex using naive scFv phage-display libraries. Reactivity and affinity of scFv clones against the cognate antigen were quantified using FACS and surface plasmon resonance. Candidate scFv clones were engineered to human IgG1 (hIgG1) and T-cell-engaging bispecific antibody (CD3xJB8). Complement-dependent cytotoxicity (CDC) and bispecific antibody-dependent cellular cytotoxicity (BADCC) were assessed. RESULTS: scFv clones A10 and B10 were isolated after bio-panning. Both A10-hIgG1 and B10-hIgG1 reacted with DNAJB8-143 peptide-pulsed antigen-presenting cells and HLA-A24(+)/DNAJB8(+) renal cell carcinoma and osteosarcoma cell lines. A10-hIgG1 and B10-hIgG1 showed strong affinity with the cognate HLA/peptide complex (KD = 2.96 × 10-9 M and 5.04 × 10-9 M, respectively). A10-hIgG1 and B10-hIgG1 showed CDC against HLA-A24(+)/DNAJB8(+) cell lines. B10-(CD3xJB8) showed superior BADCC to A10-(CD3xJB8). CONCLUSION: We isolated artificial scFv antibodies reactive to CSC/CIC antigen DNAJB8-derived peptide naturally present on renal cell carcinoma and sarcoma. Immunotherapy using these engineered antibodies could be promising.

TEG011 persistence averts extramedullary tumor growth without exerting off-target toxicity against healthy tissues in a humanized HLA-A*24:02 transgenic mice.

γδT cells play an important role in cancer immunosurveillance and are able to distinguish malignant cells from their healthy counterparts via their γδTCR. This characteristic makes γδT cells an attractive candidate for therapeutic application in cancer immunotherapy. Previously, we have identified a novel CD8α-dependent tumor-specific allo-HLA-A*24:02-restricted Vγ5Vδ1TCR with potential therapeutic value when used to engineer αßT cells from HLA-A*24:02 harboring individuals. αßT cells engineered to express this defined Vγ5Vδ1TCR (TEG011) have been suggested to recognize spatial changes in HLA-A*24:02 present selectively on tumor cells but not their healthy counterparts. However, in vivo efficacy and toxicity studies of TEG011 are still limited. Therefore, we extend the efficacy and toxicity studies as well as the dynamics of TEG011 in vivo in a humanized HLA-A*24:02 transgenic NSG (NSG-A24:02) mouse model to allow the preparation of a first-in-men clinical safety package for adoptive transfer of TEG011. Mice treated with TEG011 did not exhibit any graft-versus-host disease-like symptoms and extensive analysis of pathologic changes in NSG-A24:02 mice did not show any off-target toxicity of TEG011. However, loss of persistence of TEG011 in tumor-bearing mice was associated with the outgrowth of extramedullary tumor masses as also observed for mock-treated mice. In conclusion, TEG011 is well tolerated without harming HLA-A*24:02+ expressing healthy tissues, and TEG011 persistence seems to be crucial for long-term tumor control in vivo.

HLA-A*24:02 is associated with metronidazole-induced cutaneous adverse drug reactions in Han Chinese individuals: A pilot case-control study with both HLA gene and T cell receptor repertoire analysis.

Metronidazole, a widely used drug for the treatment of infections with anaerobic and facultative anaerobic bacteria and protozoa, can frequently cause metronidazole-induced cutaneous adverse reactions (McADRs). The aim of the present study was to investigate the association between human leucocyte antigen (HLA) alleles and McADRs in a Chinese Han population. The frequency of HLA-B*24:02 carriers among the McADR patients was 73.3%, which was significantly higher than that of the population controls (32.16%, OR = 5.80, 95% CI = [1.80-18.72], Pc = 0.004) and of the metronidazole-tolerant patients (26.67%, OR = 7.56, 95% CI = [2.02-28.35], Pc = 0.004). Molecular docking showed that metronidazole and one of its major metabolites had the potential to bind in the HLA groove and that there was a relatively stable binding state of the HLA-B*24:02-metronidazole/the metabolite complex. The CDR3 repertoires of both T cell receptor (TCR)Vα and Vß of the patients showed a significantly skewed or an oligoclonal distribution. The TCRVß CDR3 of the patients shared a similar motif, "CASSxxxxxxQxF." The current study demonstrated that both the HLA-A*24:02 allele and TCR are involved in the pathogenesis of McADRs.

Identification of an HLA-A*24:02-restricted α-fetoprotein signal peptide-derived antigen and its specific T-cell receptor for T-cell immunotherapy.

Hepatocellular carcinoma (HCC) is the most common type of liver cancer with limited treatments. Asia has the highest HCC incidence rates; China accounts for over 50% of all HCC cases worldwide. T-cell receptor (TCR) -engineered T-cell immunotherapies specific for human leukocyte antigen (HLA) -A*02:01-restricted α-fetoprotein (AFP) peptide have shown encouraging results in clinics. HLA-A*24:02 is more common than HLA-A*02:01 in Asian countries, including China. Here we identified a novel HLA-A*24:02-restricted peptide KWVESIFLIF (AFP2-11 ) located in AFP signal peptide domain by mass spectrometric analysis of HLA-bound peptides from HepG2 cells. A TCR (KWV3.1) specific for AFP2-11 -HLA-A*24:02 was isolated from peripheral blood mononuclear cells of a healthy donor. The binding affinity of soluble KWV3.1 to its antigen was determined to be ~55 µm, within the affinity range of native TCRs for self-antigens. KWV3.1-transfected T cells could specifically activate and kill AFP2-11 pulsed T2-A24 cells and AFP+  HLA-A*24:02+ tumor cell lines, demonstrating that AFP2-11 can be naturally presented on the surface of AFP+ tumor cell lines. The newly identified antigenic peptide can provide a novel target for immunotherapeutic strategies for patients with AFP+  HLA-A*24:02+ HCC.

Targeting mutant p53-expressing tumours with a T cell receptor-like antibody specific for a wild-type antigen.

Accumulation of mutant p53 proteins is frequently found in a wide range of cancers. While conventional antibodies fail to target intracellular proteins, proteosomal degradation results in the presentation of p53-derived peptides on the tumour cell surface by class I molecules of the major histocompatibility complex (MHC). Elevated levels of such p53-derived peptide-MHCs on tumour cells potentially differentiate them from healthy tissues. Here, we report the engineering of an affinity-matured human antibody, P1C1TM, specific for the unmutated p53125-134 peptide in complex with the HLA-A24 class I MHC molecule. We show that P1C1TM distinguishes between mutant and wild-type p53 expressing HLA-A24+ cells, and mediates antibody dependent cellular cytotoxicity of mutant p53 expressing cells in vitro. Furthermore, we show that cytotoxic PNU-159682-P1C1TM drug conjugates specifically inhibit growth of mutant p53 expressing cells in vitro and in vivo. Hence, p53-associated peptide-MHCs are attractive targets for the immunotherapy against mutant p53 expressing tumours.

Identification of HLA-A*24:02:78 by next-generation sequencing in a Chinese Han individual.

HLA-A*24:02:78 differs from HLA-A*24:02:01:01 in exon 3 by a single nucleotide.

Characterization of seven new HLA alleles, A*24:14:01:04, A*29:02:01:07, C*06:02:01:37, C*07:830, C*16:162, C*16:01:01:07 and DQA1*01:02:05.

Seven new HLA alleles were characterized by next generation sequencing in the Spanish population.

Development of a rapid and reliable single-tube multiplex real-time PCR method for HLA-A*24:02 genotyping.

Aim:HLA-A*24:02 is significantly associated with cutaneous adverse drug reactions caused by aromatic antiepileptic drugs. Here, we aimed to establish a fast and reliable detection method for HLA-A*24:02 genotyping. Methods: A single-tube multiplex quantitative real-time polymerase chain reaction (qPCR) assay for HLA-A*24:02 genotyping was established by combining allele-specific primers with TaqMan probes. Results: A 100% concordance was observed between qPCR and SBT result in 106 Han subjects. The detection limit of the new method was 0.05 ng DNA. The positive rate of HLA-A*24:02 in Tibetans (55.6%, n = 81) was significantly higher than those in Han (34%, n = 106), Uighur (27.5%, n = 102), Bouyei (25.9%, n = 116) and Miao populations (26.5%, n = 113). Conclusion: The newly established qPCR assay was reliable for HLA-A*24:02 screening in clinical applications.