Association of HLA alleles with cephalosporin allergy in the Taiwanese population.

Cephalosporin antibiotics are widely used in clinical settings, but they can cause hypersensitivity reactions, which may be influenced by genetic factors such as the expression of Human leukocyte antigen (HLA) molecules. This study aimed to investigate whether specific HLA alleles were associated with an increased risk of adverse reactions to cephalosporins among individuals in the Taiwanese population. This retrospective case-control study analyzed data from the Taiwan Precision Medicine Initiative (TPMI) on 27,933 individuals who received cephalosporin exposure and had HLA allele genotyping information available. Using logistic regression analyses, we examined the associations between HLA genotypes, comorbidities, allergy risk, and severity. Among the study population, 278 individuals had cephalosporin allergy and 2780 were in the control group. Our results indicated that certain HLA alleles, including HLA-B*55:02 (OR = 1.76, 95% CI 1.18-2.61, p = 0.005), HLA-C*01:02 (OR = 1.36, 95% CI 1.05-1.77, p = 0.018), and HLA-DQB1*06:09 (OR = 2.58, 95% CI 1.62-4.12, p < 0.001), were significantly associated with an increased risk of cephalosporin allergy reactions. Additionally, the HLA-C*01:02 allele genotype was significantly associated with a higher risk of severe allergy (OR = 2.33, 95% CI 1.05-5.15, p = 0.04). This study identified significant associations between HLA alleles and an increased risk of cephalosporin allergy, which can aid in early detection and prediction of adverse drug reactions to cephalosporins. Furthermore, our study highlights the importance of HLA typing in drug safety and expanding our knowledge of drug hypersensitivity syndromes.

Human leukocyte antigen HLA-B*57:01 status in HIV-1 patients developing hypersensitivity reactions in Benin: a pilot study.

BACKGROUND: Antiretroviral drugs in people living with HIV-1 (PLHIV-1) often trigger side effects which may lead to discontinuation or failure of treatment. Human Leukocyte Antigen B*57:01 (HLA-B*57:01) allele is known to predict hypersensitivity reactions to Abacavir. Very few data are available on the prevalence of HLA-B*57:01 allele in PLHIV-1 in African countries. This study aimed to screen for HLA-B*57:01 allele in PLHIV-1 in Benin. METHODS: This pilot study was carried out on one hundred ten PLHIV-1 enrolled in two health facilities in Benin. Socio-demographic and clinical data were collected. Biological data were determined and HLA-B*57:01 allele was genotyped, using Single Specific Primer-Polymerase Chain Reaction in blood samples. RESULTS: 70% of participants were female. PLHIV-1 were under TDF + 3TC + DTG (47.2%) or TDF + 3TC + EFV (57.3%). Their median age was 41 [36-48.75] years and the average CD4 + T cell count was 249 [130-381.25] cells/µl. The average viral load in treatment failure PLHIV-1 was 4.7 [3.9-5.2] Log10. At the inclusion date, twenty-nine (26.4%) PLHIV-1 under TDF + 3TC + EFV have developed hypersensitivity reactions. None of 110 patients had shown HLA-B*5701 allele. CONCLUSION: Our study revealed that HLA-B*57:01 allele was very rare in PLHIV-1 in Benin, suggesting that its screening before starting the Abacavir regimen did not seem necessary.

Anticipating the side effects of benznidazole: HLA-B*35 and patch test.

INTRODUCTION: Treatment of Chagas disease frequently causes distress to patients due to a high incidence of adverse effects. Different preemptive tests have been researched to prevent these effects and to allow focus to be given to certain predisposed patients. Benznidazole is the most prescribed Chagas disease treatment in Spain. In this work, we analyzed the genetic markers HLA-B*35 allele group and HLA-B*35:05 allele specifically, as well as an allergy patch test, as benznidazole's most frequent adverse effects are cutaneous. METHODS: HLA-B intermediate-resolution genotyping was performed followed by a high-resolution level analysis. Cutaneous allergies were tested using strips impregnated with a mixture of benznidazole and placed on the upper back of patients before starting treatment. RESULTS: In our sample of more than 400 patients, there was almost no relationship between any kind of side effect and either of the HLA-B alleles studied. The patch testing was quickly discarded as a preemptive test due to its low sensitivity (16.7%). CONCLUSION: In conclusion, we were unable to replicate and corroborate genetic markers identified by other groups and there is currently no test that can anticipate the adverse effects of benznidazole, therefore, more investigation should be carried out in this field.

Polymorphisms of HLA genes and hypersensitivity to penicillin among patients in a Taiwanese population.

Penicillin allergy is a potentially life-threatening condition that is common among patients. However, the genetic associations with penicillin allergy are not yet recognized for prevention or diagnosis, particularly in East Asian populations. We conducted a retrospective case-control study using data from the Taiwan Precision Medicine Initiative and analysing DNA samples to identify eight major MHC Class I and Class II loci. We employed imputation methods for accurate HLA typing and enrolled 17,827 individuals who received penicillin. Logistic regression analyses were utilized to explore associations between HLA genotypes, comorbidities and allergy risk, while simultaneously conducting a subgroup analysis to explore the association between HLA genotypes, comorbidities and the severity of allergic reactions. Our study assigned 496 cases to the penicillin allergy group and 4960 controls to a matched group. The risk of penicillin allergy was significantly higher with HLA-DPB1*05:01 (OR = 1.36, p = .004) and HLA-DQB1*05:01 (OR = 1.54, p = .03), with adjusted p-values of .032 and .24, respectively. Urticaria was identified as a separate risk factor (OR = 1.73, p < .001). However, neither the HLA alleles nor the comorbidities had a significant relationship with the risk of severe penicillin-induced allergy. HLA-DPB1*05:01 was found to be significantly associated with penicillin allergy reactions among the Taiwanese population.

Identificación del alelo HLA B*57: 01 en una población militar, de Lima-Perú / Identification of the allele HLA B*57: 01 in a military population, from Lima-Peru

El alelo HLA B*57:01 es un marcador genético asociado con la hipersensibilidad al fármaco anti-retroviral abacavir (ABC) y su frecuencia en la población peruana todavía es desconocida. El objetivo fue identificar el alelo HLA B*57:01 en una población militar de Lima, Perú. Se reclutaron 43 personas viviendo con VIH (PVV) quienes aceptaron participar a través de un consentimiento informado. La detección del alelo HLA B*57:01 se realizó mediante RPC en tiempo real (RT-PCR). Asimismo, se determinó la carga viral (CV), el recuento de linfocitos CD4 y la genotipificación del VIH. Se identificaron dos casos positivos al alelo HLA B*57:01 (4,7%). Además, uno de ellos presentó múltiples mutaciones de resistencia a los anti-retrovirales (ARV), incluyendo ABC. Se demostró por primera vez en el Perú la presencia del alelo HLA B*57:01.

The HLA B*57:01 allele is a genetic marker associated with hypersensitivity to the antiretroviral Abacavir (ABC) and its frequency in the Peruvian population is still unknown. The objective was to identify the HLA B*57:01 allele in a military population from Lima, Peru. Forty three people living with HIV (PLWH) were recruited, who agreed to participate through informed consent. Detection of the HLA B*57:01 allele was performed by real-time PCR (RT-PCR). Likewise, viral load (VL), CD4 lymphocyte count and HIV genotyping were determined. Two cases positive for the HLA B*57:01 allele (4.7%) were identified. In addition, one of them had multiple resistance mutations to antiretrovirals (ARVs), including ABC. The presence of the HLA B*57:01 allele was demonstrated for the first time in Peru.

Clinical characteristics and genetic HLA marker for patients with oxaliplatin-induced adverse drug reactions.

BACKGROUND: Oxaliplatin is commonly used to treat gastrointestinal malignancies. However, its applications are limited due to potential adverse drug reactions (ADRs), particularly severe anaphylactic shock. There is no method to predict or prevent ADRs caused by oxaliplatin. Therefore, we aimed to investigate the genetic HLA predisposition and immune mechanism of oxaliplatin-induced ADRs. METHODS: A retrospective review was performed for 154 patients with ADRs induced by oxaliplatin during 2016-2021 recorded in our ADR notification system. HLA genotyping was conducted for 47 patients with oxaliplatin-induced ADRs, 1100 general population controls, and 34 oxaliplatin-tolerant controls in 2019-2023. The in vitro basophil activation test (BAT) was performed and oxaliplatin-specific IgE levels were determined. RESULTS: The incidence of oxaliplatin-induced ADRs and anaphylactic shock in our cohort was 7.1% and 0.15%, respectively. Of the 154 patients, 67.5% suffered rash/eruption; 26.0% of the patients who could not undergo oxaliplatin rechallenge were considered to show oxaliplatin-induced immune-mediated hypersensitivity reactions (HRs). The genetic study found that the HLA-DRB∗12:01 allele was associated with oxaliplatin-induced HRs compared to the general population controls (sensitivity = 42.9%; odds ratio [OR] = 3.4; 95% CI = 1.4-8.2; P = 0.008) and tolerant controls (OR = 12; 95% CI = 2.3-63.7; P = 0.001). The in vitro BAT showed higher activation of CD63+ basophils in patients with oxaliplatin-induced HRs compared to the tolerant controls (P < 0.05). Only four patients (8.5%) with oxaliplatin-induced ADRs were positive for oxaliplatin-specific IgE. CONCLUSIONS: This study found that 26.0% of patients with oxaliplatin-induced ADRs could not undergo oxaliplatin rechallenge. HLA-DRB∗12:01 is regarded as a genetic marker for oxaliplatin-induced hypersensitivity.

Overview and Current Advances in Dapsone Hypersensitivity Syndrome.

PURPOSE OF REVIEW: As a sulfone antibacterial agent, dapsone has been widely used to treat leprosy. Moreover, dapsone is also used in many immune diseases such as herpetic dermatitis because of its anti-inflammatory and immunomodulatory effects. However, dapsone can cause several adverse effects, the most serious being dapsone hypersensitivity syndrome. Dapsone hypersensitivity syndrome is characterized by a triad of eruptions, fever, and organ involvement, which limits the application of dapsone to some extent. RECENT FINDINGS: In this article, we review current research about the interaction model between HLA-B*13:01, dapsone, and specific TCR in dapsone-induced drug hypersensitivity. In addition to the proposed mechanisms, we also discussed clinical features, treatment progress, prevalence, and prevention of dapsone hypersensitivity syndrome. These studies reveal the pathogenesis, clinical features, and prevalence from the perspectives of genetic susceptibility and innate and adaptive immunity in dapsone hypersensitivity syndrome, thereby guiding clinicians on how to diagnose, prevent, and treat dapsone hypersensitivity syndrome.

The Prevalence of HLA-B*57 Serotype Associated with Hypersensitivity Reactions in the Treatment of HIV Infection in the Turkish Population.

OBJECTIVES: The aim of our study is to reveal the prevalence of HLA-B*57 in the Turkish population and to provide new perspectives to physicians starting abacavir therapy in HIV patients. BACKGROUND: Abacavir, one of the drugs used to treat HIV infection, can cause hypersensitivity reactions in some patients. These hypersensitivity reactions have been shown to be associated with the HLA-B*57:01 allele. High-resolution HLA-B*57:01 scanning has a time and cost disadvantage compared with low-resolution HLA-B*57 scanning. Before starting abacavir treatment, we will discuss whether high-resolution scanning is more beneficial in individuals who are positive on HLAB* 57 screening. This is the study with the largest cohort to investigate the prevalence of HLA-B*57 in Turkey. METHODS: The results of 25 thousand 318 people who applied to Bursa Uludag University Faculty of Medicine, Department of Immunology for HLA-B* typing were scanned. RESULTS: In our study, the HLA-B*57 serotype was detected in 827 (3.3%) individuals. CONCLUSION: Considering these results, it can be assumed that the prevalence of HLA-B*57:01 in Turkey is lower than 3.3%. Instead of a high-resolution HLA-B*57:01 scan in all patients starting abacavir therapy, a high-resolution HLA-B*57:01 scan might be of greater benefit in patients who are positive on a low-resolution HLA-B*57 scan.

Transgenic murine models for the study of drug hypersensitivity reactions linked to HLA-I molecules.

PURPOSE OF REVIEW: Immune-mediated drug hypersensitivity reactions (DHRs) can be life-threatening and an impediment to drug development. Mechanism of disease studies are difficult to perform in humans. Here we review human leukocyte antigens class I (HLA-I) transgenic murine models and highlight how these systems have helped to elucidate drug-specific and host immune factors that initiate, propagate and control severe drug toxicities to skin and liver. RECENT FINDINGS: HLA transgenic mice have been developed and used to study immune-mediated drug reactions in vitro and in vivo . CD8+ T cells from HLA-B∗57:01-expressing mice respond strongly to abacavir (ABC) in vitro but have self-limited responses to drug exposure in vivo . Immune tolerance can be overcome by depleting regulatory T cells (Treg) allowing antigen-presenting dendritic cells to express CD80/86 costimulatory molecules and signal through CD28 on the CD8+ T cell. Depletion of Treg also removes competition for interleukin 2 (IL-2) to allow T cell expansion and differentiation. Fine tuning of responses depends on inhibitory checkpoint molecules such as PD-1. Improved mouse models express only HLA in the absence of PD-1. These models show enhanced liver injury to flucloxacillin (FLX) which depends on drug priming, CD4+ T cell depletion, and lack of PD-1 expression. Drug-specific HLA-restricted cytotoxic CD8+ T cells can infiltrate the liver but are suppressed by Kupffer and liver sinusoidal endothelial cells. SUMMARY: HLA-I transgenic mouse models are now available to study ABC, FLX and carbamazepine-induced adverse reactions. In vivo studies range from characterizing drug-antigen presentation, T cell activation, immune-regulatory molecules and cell-cell interaction pathways that are specifically involved in causing or controlling unwanted DHRs.

Characterization of Drug-Specific CD4+ T-Cells Reveals Possible Roles of HLA Class II in the Pathogenesis of Carbamazepine Hypersensitivity Reactions.

Carbamazepine (CBZ) is an aromatic anticonvulsant known to cause drug hypersensitivity reactions, which range in severity from relatively mild maculopapular exanthema to potentially fatal Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS-TEN). These reactions are known to be associated with human leukocyte antigen (HLA) class I alleles, and CBZ interacts preferentially with the related HLA proteins to activate CD8+ T-cells. This study aimed to evaluate the contribution of HLA class II in the effector mechanism(s) of CBZ hypersensitivity. CBZ-specific T-cells clones were generated from two healthy donors and two hypersensitive patients with high-risk HLA class I markers. Phenotype, function, HLA allele restriction, response pathways, and cross-reactivity of CBZ-specific T-cells were assessed using flow cytometry, proliferation analysis, enzyme-linked immunosorbent spot, and enzyme-linked immunosorbent assay. The association between HLA class II allele restriction and CBZ hypersensitivity was reviewed using Allele Frequency Net Database. Forty-four polyclonal CD4+ CBZ-specific T-cell clones were generated and found to be restricted to HLA-DR, particularly HLA-DRB1*07:01. This CD4+-mediated response proceeded through a direct pharmacological interaction between CBZ and HLA-DR molecules. Similar to the CD8+ response, CBZ-stimulated CD4+ clones secreted granulysin, a key mediator of SJS-TEN. Our database review revealed an association between HLA-DRB1*07:01 and CBZ-induced SJS-TEN. These findings implicate HLA class II antigen presentation as an additional pathogenic factor for CBZ hypersensitivity reactions. Both HLA class II molecules and drug-responsive CD4+ T-cells should be evaluated further to gain better insights into the pathogenesis of drug hypersensitivity reactions.

Next-generation sequencing-based HLA typing reveals the association of HLA-B*46:01:01 and HLA-DRB1*09:01:02 alleles with carbamazepine-induced hypersensitivity reactions in Vietnamese patients with epilepsy.

Several studies have reported an association between certain human leukocyte antigen (HLA) alleles and carbamazepine (CBZ)-induced hypersensitivity reactions in patients with epilepsy. Here, the relationship between the clinical spectrum and the HLA allele profiles in patients with CBZ-induced hypersensitivity reactions was investigated using next-generation sequence (NGS) data obtained from 65 Vietnamese patients with epilepsy, including 33 with CBZ-tolerance and 32 patients with CBZ-hypersensitivity, in which only 8 with severe cutaneous adverse drug reactions and 24 were mild-hypersensitive patients. Three loci of HLA class I (HLA-A, -B, and -C) and two loci of HLA class II (HLA-DQA1 and -DRB1) were included in our analysis. We observed a higher prevalence of three alleles, HLA-B*46:01:01, HLA-DQA1*03:02:01, and HLA-DRB1*09:01:02, in the CBZ hypersensitivity group compared to that in the CBZ tolerant group. Notably, all hypersensitive patients with HLA-DQA1*03:02:01 also harbored HLA-DRB1*09:01:02. We also used molecular modeling to gain mechanistic insight into the interactions of HLA-B*46:01 and HLA-DRB1*09:01 with CBZ. Our findings proposed the direct interaction of CBZ with peptide-binding pockets of these HLA proteins. The sensitivity and specificity of HLA-B*46:01:01 in considering with the appearance of HLA-DRB1*09:01:02 were 46.88% and 84.85%, respectively. Our data suggest that the presence of HLA-B*46:01:01/HLA-DRB1*09:01:02 is a potential marker of CBZ-induced hypersensitivity reactions in Vietnamese patients.

Association of Human Leukocyte Antigen Alleles and Hypersensitivity of Efavirenz/Nevirapine in HIV-Infected Chinese Patients.

To examine the association between human leukocyte antigen (HLA) and nevirapine (NVP)- and efavirenz (EFV)-induced cutaneous adverse reactions in human immunodeficiency virus (HIV) patients, we conducted a case-control study at our center consisting of 96 patients. Patients were further assigned based on the occurrence of cutaneous adverse events and the drugs involved. All patients were subjected to next generation sequencing (NGS)-based screening with focus on HLA phenotype, including the presence of HLA-B, HLA-C, and HLA-DRB1. Our data indicated that the HLA-C*01:02:01 allele presence was observed in 47.4% (18/38) of patients in the EFV-hypersensitivity group compared with 18.9% (7/30) in the control group [odds ratio (OR) = 5.837; 95% confidence interval (CI) = 1.727-19.722, p = .005]. In contrast, the occurrence of HLA-DRB1*08:03 was found to be significantly lower in the EFV-hypersensitivity group (4/38, 10.5%) compared with the corresponding control group (12/37, 32.4%) (OR = 0.148; 95% CI = 0.035-0.625, p = .009). In addition, the HLA-DRB1*04:05:01 antigen was expressed more frequently in the NVP-hypersensitivity group (23.8%, 5/21) compared with the control group (10.8%, 4/37) (OR = 7; 95% CI = 1.265-38.793, p = .026). Our data not only revealed a significant association between HLA-C*01:02:01 and EFV-induced cutaneous adverse reactions but may also shed light on defining the treatment for Chinese HIV patients.

A low-cost, sensitive and specific PCR-based tool for rapid clinical detection of HLA-B*35 alleles associated with delayed drug hypersensitivity reactions.

HLA (HLA) alleles are risk factors for CD8+ T-cell-mediated drug hypersensitivity reactions. However, as most HLA associations are incompletely predictive and/or involve risk alleles at low frequency, costly sequence-based typing can elude an economically productive cost: benefit ratio for clinical validation studies and diagnostic and/or preventative screening. Hence rapid and low-cost detection assays are now required, both for single alleles but also across risk loci associated with broader multi-disease risk; exemplified by associations with diverse alleles in HLA-B*35, including HLA-B*35:01 and green tea- or co-trimoxazole-induced liver injury. Here, we developed a cost-effective (<$10USD) qPCR assay for rapid (<2.5 h) clinical detection of HLA-B*35 alleles. The assay was validated using 430 DNA samples with previous American society for histocompatibility and immunogenetics-accredited sequence-based high-resolution HLA typing, positively detecting all HLA-B*35 allelic variants in our cohort, and as expected by primer design, the six samples that expressed low-frequency B*78:01. The assay did not result in positive detection for any negative control allele. With expected detection of B*35 and B*78, our assay sensitivity (95% CI, 95.07%-100.00%) and specificity (95% CI, 98.97%-100.00%) of 100% using as low as 10 ng of DNA provides a reliable HLA-B*35 screening tool for clinical validation and HLA-risk-based prevention and diagnostics.

Functional and structural characteristics of HLA-B*13:01-mediated specific T cells reaction in dapsone-induced drug hypersensitivity.

BACKGROUND: Severe cutaneous adverse drug reactions (SCARs) are a group of serious clinical conditions caused by immune reaction to certain drugs. The allelic variance of human leukocyte antigens of HLA-B*13:01 has been strongly associated with hypersensitivities induced by dapsone (DDS). T-cell receptor mediated activation of cytotoxic T lymphocytes (CTLs) has also been suggested to play an essential role in pathogenesis of SCARs. However, HLA-B*13:01-DDS-TCR immune synapse that plays role in drug-induced hypersensitivity syndrome (DIHS) associated T cells activation remains uncharacterized. METHODS: To investigate the molecular mechanisms for HLA-B*13:01 in the pathogenesis of Dapsone-induced drug hypersensitivity (DDS-DIHS), we performed crystallization and expanded drug-specific CTLs to analyze the pathological role of DDS-DIHS. RESULTS: Results showed the crystal structure of HLA-B*13:01-beta-2-microglobulin (ß2M) complex at 1.5 Å resolution and performed mutation assays demonstrating that I118 or I119, and R121 of HLA-B*13:01 were the key residues that mediate the binding of DDS. Subsequent single-cell TCR and RNA sequencing indicated that TCRs composed of paired TRAV12-3/TRBV28 clonotype with shared CDR3 region specifically recognize HLA-B*13:01-DDS complex to trigger inflammatory cytokines associated with DDS-DIHS. CONCLUSION: Our study identified the novel p-i-HLA/TCR as the model of interaction between HLA-B*13:01, DDS and the clonotype-specific TCR in DDS-DIHS.

HLA pharmacogenetic markers of drug hypersensitivity from the perspective of the populations of the Greater Middle East.

Specific HLA associations with drug hypersensitivity may vary between geographic regions and ethnic groups. There are little to no data related to HLA-drug hypersensitivity on populations who reside in the Greater Middle East (GME), a vast region spanning from Morocco in the west to Pakistan in the east. In this review, the authors intended to summarize the significant HLA alleles associated with hypersensitive drug reactions induced by different drugs, as have been found in different populations, and to summarize the prevalence of these alleles in the specific and diverse populations of the GME. For example, HLA-B*57:01 allele prevalence, associated with abacavir-induced hypersensitivity, ranges from 1% to 3%, and HLA-DPB1*03:01 prevalence, associated with aspirin-induced asthma, ranges from 10% to 14% in the GME population. Studying pharmacogenomic associations in the ethnic groups of the GME may allow the discovery of new associations, confirm ones found with a low evidence rate and enable cost-effectiveness analysis of allele screening before drug use.