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A strong genetic predictor of outcome following untreated HIV-1 infection is the carriage of specific alleles of human leukocyte antigens (HLAs) that present viral epitopes to T cells. Residual variation in outcome measures may be attributed, in part, to viral adaptation to HLA-restricted T cell responses. Variants of the endoplasmic reticulum aminopeptidases (ERAPs) influence the repertoire of T cell epitopes presented by HLA alleles as they trim pathogen-derived peptide precursors to optimal lengths for antigen presentation, along with other functions unrelated to antigen presentation. We investigated whether ERAP variants influence HLA-associated HIV-1 adaptation with demonstrable effects on overall HIV-1 disease outcome. Utilizing host and viral data of 249 West Australian individuals with HIV-1 subtype B infection, we identified a novel association between two linked ERAP2 single nucleotide polymorphisms (SNPs; rs2248374 and rs2549782) with plasma HIV RNA concentration (viral load) (P adjusted = 0.0024 for both SNPs). Greater HLA-associated HIV-1 adaptation in the HIV-1 Gag gene correlated significantly with higher viral load, lower CD4+ T cell count and proportion; P = 0.0103, P = 0.0061, P = 0.0061, respectively). When considered together, there was a significant interaction between the two ERAP2 SNPs and HLA-associated HIV-1 adaptation on viral load (P = 0.0111). In a comprehensive multivariate model, addition of ERAP2 haplotypes and HLA associated adaptation as an interaction term to known HLA and CCR5 determinants and demographic factors, increased the explanatory variance of population viral load from 17.67% to 45.1% in this dataset. These effects were not replicated in publicly available datasets with comparably sized cohorts, suggesting that any true global epistasis may be dependent on specific HLA-ERAP allelic combinations. Our data raises the possibility that ERAP2 variants may shape peptide repertoires presented to HLA class I-restricted T cells to modulate the degree of viral adaptation within individuals, in turn contributing to disease variability at the population level. Analyses of other populations and experimental studies, ideally with locally derived ERAP genotyping and HLA-specific viral adaptations are needed to elucidate this further.
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Aminopeptidasas , Epistasis Genética , Infecciones por VIH , VIH-1 , Polimorfismo de Nucleótido Simple , Humanos , Aminopeptidasas/genética , Infecciones por VIH/inmunología , Infecciones por VIH/genética , Infecciones por VIH/virología , VIH-1/inmunología , VIH-1/genética , Australia , Masculino , Femenino , Antígenos HLA/genética , Carga Viral , Adulto , Persona de Mediana EdadRESUMEN
Adaptation to human leukocyte antigen (HLA)-associated immune pressure represents a major driver of human immunodeficiency virus (HIV) evolution at both the individual and population level. To date, there has been limited exploration of the impact of the initial cellular immune response in driving viral adaptation, the dynamics of these changes during infection and their effect on circulating transmitting viruses at the population level. Capturing detailed virological and immunological data from acute and early HIV infection is challenging as this commonly precedes the diagnosis of HIV infection, potentially by many years. In addition, rapid initiation of antiretroviral treatment following a diagnosis is the standard of care, and central to global efforts towards HIV elimination. Yet, acute untreated infection is the critical period in which the diversity of proviral reservoirs is first established within individuals, and associated with greater risk of onward transmissions in a population. Characterizing the viral adaptations evident in the earliest phases of infection, coinciding with the initial cellular immune responses is therefore relevant to understanding which changes are of greatest impact to HIV evolution at the population level. In this study, we utilized three separate cohorts to examine the initial CD8+ T cell immune response to HIV (cross-sectional acute infection cohort), track HIV evolution in response to CD8+ T cell-mediated immunity over time (longitudinal chronic infection cohort) and translate the impact of HLA-driven HIV evolution to the population level (cross-sectional HIV sequence data spanning 30 years). Using next generation viral sequencing and enzyme-linked immunospot interferon-gamma recall responses to peptides representing HLA class I-specific HIV T cell targets, we observed that CD8+ T cell responses can select viral adaptations prior to full antibody seroconversion. Using the longitudinal cohort, we uncover that viral adaptations have the propensity to be retained over time in a non-selective immune environment, which reflects the increasing proportion of pre-adapted HIV strains within the Western Australian population over an approximate 30-year period.
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Infecciones por VIH , VIH-1 , Humanos , Estudios Transversales , Australia , Antígenos de Histocompatibilidad Clase I , Antígenos HLA , Antígenos de Histocompatibilidad Clase II , Linfocitos T CD8-positivosRESUMEN
Severe cutaneous adverse reactions (SCARs) such as Stevens-Johnson syndrome, toxic epidermal necrolysis (SJS/TEN), and drug reaction with eosinophilia and systemic symptoms (DRESS)/drug-induced hypersensitivity syndrome (DIHS) cause significant morbidity and mortality and impede new drug development. HLA class I associations with SJS/TEN and drug reaction with eosinophilia and systemic symptoms/drug-induced hypersensitivity syndrome have aided preventive efforts and provided insights into immunopathogenesis. In SJS/TEN, HLA class I-restricted oligoclonal CD8+ T-cell responses occur at the tissue level. However, specific HLA risk allele(s) and antigens driving this response have not been identified for most drugs. HLA risk alleles also have incomplete positive and negative predictive values, making truly comprehensive screening currently challenging. Although, there have been key paradigm shifts in knowledge regarding drug hypersensitivity, there are still many open and unanswered questions about SCAR immunopathogenesis, as well as genetic and environmental risk. In addition to understanding the cellular and molecular basis of SCAR at the single-cell level, identification of the MHC-restricted drug-reactive self- or viral peptides driving the hypersensitivity reaction will also be critical to advancing premarketing strategies to predict risk at an individual and drug level. This will also enable identification of biologic markers for earlier diagnosis and accurate prognosis, as well as drug causality and targeted therapeutics.
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Síndrome de Hipersensibilidad a Medicamentos , Eosinofilia , Síndrome de Stevens-Johnson , Humanos , Síndrome de Hipersensibilidad a Medicamentos/etiología , Síndrome de Hipersensibilidad a Medicamentos/genética , Síndrome de Stevens-Johnson/genética , GenómicaAsunto(s)
Aminoglicósidos/efectos adversos , Síndrome de Hipersensibilidad a Medicamentos/genética , Antígenos HLA-A/genética , Haplotipos , Lipoglucopéptidos/efectos adversos , Teicoplanina/efectos adversos , Vancomicina/efectos adversos , Aminoglicósidos/administración & dosificación , Síndrome de Hipersensibilidad a Medicamentos/inmunología , Antígenos HLA-A/inmunología , Humanos , Lipoglucopéptidos/administración & dosificación , Teicoplanina/administración & dosificación , Vancomicina/administración & dosificaciónRESUMEN
BACKGROUND: Germ cell tumors of the ovary constitute less than one percent of ovarian tumors worldwide. Choriocarcinoma arising de novo from the ovary is very rare and only occasionally reported in the literature. Herein, we report a case of bilateral non-gestational pure primary ovarian choriocarcinoma that was confirmed by beta human chorionic gonadotropin (ß-HCG) levels and histopathology. CASE REPORT: Our case is of a middle-aged multiparous female who presented with amenorrhea for three months. She underwent an evaluation with ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI), which revealed bilateral bulky solid adnexal masses. Based on an increased blood level of the beta human chorionic gonadotropin and a histopathological examination, the diagnosis of bilateral non-gestational pure primary ovarian choriocarcinoma was made. CONCLUSIONS: The imaging findings were found to be specific for bilateral non-gestational pure primary ovarian choriocarcinoma.
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UNLABELLED: The interaction between hepatitis C virus (HCV) and cellular immune responses during very early infection is critical for disease outcome. To date, the impact of antigen-specific cellular immune responses on the evolution of the viral population establishing infection and on potential escape has not been studied. Understanding these early host-virus dynamics is important for the development of a preventative vaccine. Three subjects who were followed longitudinally from the detection of viremia preseroconversion until disease outcome were analyzed. The evolution of transmitted/founder (T/F) viruses was undertaken using deep sequencing. CD8(+) T cell responses were measured via enzyme-linked immunosorbent spot (ELISpot) assay using HLA class I-restricted T/F epitopes. T/F viruses were rapidly extinguished in all subjects associated with either viral clearance (n = 1) or replacement with viral variants leading to establishment of chronic infection (n = 2). CD8(+) T cell responses against 11 T/F epitopes were detectable by 33 to 44 days postinfection, and 5 of these epitopes had not previously been reported. These responses declined rapidly in those who became chronically infected and were maintained in the subject who cleared infection. Higher-magnitude CD8(+) T cell responses were associated with rapid development of immune escape variants at a rate of up to 0.1 per day. Rapid escape from CD8(+) T cell responses has been quantified for the first time in the early phase of primary HCV infection. These rapid escape dynamics were associated with higher-magnitude CD8(+) T cell responses. These findings raise questions regarding optimal selection of immunogens for HCV vaccine development and suggest that detailed analysis of individual epitopes may be required. IMPORTANCE: A major limitation in our detailed understanding of the role of immune response in HCV clearance has been the lack of data on very early primary infection when the transmitted viral variants successfully establish the acute infection. This study was made possible through the availability of specimens from a unique cohort of asymptomatic primary infection cases in whom the first available viremic samples were collected approximately 3 weeks postinfection and at regular intervals thereafter. The study included detailed examination of both the evolution of the viral population and the host cellular immune responses against the T/F viruses. The findings here provide the first evidence of host cellular responses targeting T/F variants and imposing a strong selective force toward viral escape. The results of this study provide useful insight on how virus escapes the host response and consequently on future analysis of vaccine-induced immunity.
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Linfocitos T CD8-positivos/inmunología , Hepacivirus/inmunología , Hepacivirus/patogenicidad , Hepatitis C/inmunología , Hepatitis C/virología , Enfermedad Aguda , Adulto , Secuencia de Aminoácidos , Anticuerpos Antivirales/sangre , Progresión de la Enfermedad , Epítopos de Linfocito T/genética , Epítopos de Linfocito T/inmunología , Evolución Molecular , Hepacivirus/genética , Antígenos de la Hepatitis/genética , Antígenos de la Hepatitis/inmunología , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/virología , Interacciones Huésped-Patógeno , Humanos , Inmunidad Celular , Masculino , Mutación , Polimorfismo de Nucleótido Simple , Selección Genética , Factores de Tiempo , Vacunas contra Hepatitis Viral/inmunología , Carga Viral , Adulto JovenRESUMEN
CONTEXT: With aging, the detrimental effects of stress can impair a person's ability to learn and sustain memory. Humor and its associated mirthful laughter can reduce stress by decreasing the hormone cortisol. Chronic release of cortisol can damage hippocampal neurons, leading to impairment of learning and memory. Objectives ⢠The study intended to examine the effect of watching a humor video on short-term memory in older adults. Design ⢠The research team designed a randomized, controlled trial. SETTING: The study took place at Loma Linda University in Loma Linda, CA, USA. PARTICIPANTS: The study included 30 participants: 20 normal, healthy, older adults-11 males and 9 females-and 10 older adults with type 2 diabetes mellitus (T2DM)-6 males and 4 females. INTERVENTION: The study included 2 intervention groups of older adults who viewed humorous videos, a healthy group (humor group), aged 69.9 ± 3.7 y, and the diabetic group, aged 67.1 ± 3.8 y. Each participant selected 1 of 2 humorous videos that were 20 min in length, either a Red Skeleton comedy or a montage of America's Funniest Home Videos. The control group, aged 68.7 ± 5.5 y, did not watch a humor video and sat in quiescence. OUTCOME MEASURES: A standardized, neuropsychological, memory-assessment tool, the Rey Auditory Verbal Learning Test (RAVLT), was used to assess the following abilities: (1) learning, (2) recall, and (3) visual recognition. The testing occurred twice, once before (RAVLT1) and once after (RAVLT2) the humorous video for the humor and diabetic groups, and once before (RAVLT1) and once after (RAVLT2) the period of quiescence for the control group. At 5 time points, measurements of salivary cortisol were also obtained. The Kruskal-Wallis test was used to measure significance of the data based on the 3 groups. RESULTS: In the humor, diabetic, and control groups, (1) learning ability improved by 38.5%, 33.4%, and 24.0%, respectively (P = .025); (2) delayed recall improved by 43.6%, 48.1%, and 20.3%, respectively (P = .064); and (3) visual recognition increased by 12.6%, 16.7%, and 8.3%, respectively (P = .321). For levels of salivary cortisol, the research team found significant and borderline decreases for the humor group between baseline and (1) post-RAVLT1 (P = .047), (2) postvideo (P = .046), and (3) post-RAVLT2 (P = .062). The diabetic group showed significant decreases between baseline and (1) post-RAVLT1 (P = .047), (2) postvideo (P = .025), and (3) post-RAVLT2 (P = .034). The study found no significant changes for the control group. CONCLUSION: The research findings supported potential clinical and rehabilitative benefits for humor that can be applied to whole-person wellness programs for older adults. The cognitive components-learning ability and delayed recall-become more challenging as individuals age and are essential to older adults for providing a high quality of life: mind, body, and spirit. Because older adults can experience age-related memory deficits, complementary, enjoyable, and beneficial humor therapies should be implemented for them.
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Diabetes Mellitus Tipo 2/psicología , Diabetes Mellitus Tipo 2/terapia , Risoterapia , Risa/fisiología , Memoria a Corto Plazo/fisiología , Anciano , Femenino , Humanos , Hidrocortisona/metabolismo , Masculino , Persona de Mediana Edad , Saliva/metabolismoRESUMEN
Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) is a rare but life-threatening cutaneous drug reaction mediated by human leukocyte antigen (HLA) class I-restricted CD8+ T-cells. To obtain an unbiased assessment of SJS/TEN cellular immunopathogenesis, we performed single-cell (sc) transcriptome, surface proteome, and TCR sequencing on unaffected skin, affected skin, and blister fluid from 17 SJS/TEN patients. From 119,784 total cells, we identified 16 scRNA-defined subsets, confirmed by subset-defining surface protein expression. Keratinocytes upregulated HLA and IFN-response genes in the affected skin. Cytotoxic CD8+ T-cell subpopulations of expanded and unexpanded TCRαß clonotypes were shared in affected skin and blister fluid but absent or unexpanded in SJS/TEN unaffected skin. SJS/TEN blister fluid is a rich reservoir of oligoclonal CD8+ T-cells with an effector phenotype driving SJS/TEN pathogenesis. This multiomic database will act as the basis to define antigen-reactivity, HLA restriction, and signatures of drug-antigen-reactive T-cell clonotypes at a tissue level.
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BACKGROUND: It is well established that there is a reduction in the skin blood flow (SBF) in response to heat with age and diabetes. While it is known that high BMI creates a stress on the cardiovascular system and increases the risk of all cause of morbidity and mortality, little is known of the effect of high BMI on SBF response to heat. Since diabetes is associated with age and a higher BMI, the interrelationship between age, BMI and SBF needs to be investigated to better understand the contribution diabetes alone has to endothelial impairment. MATERIAL AND METHODS: This study examined the SBF to heat in young and old people with low and high BMI and people with diabetes with high BMI to determine the contribution these variables have on SBF. Subjects were ten young and older people with BMI <20 and ten young and older people with BMI >20 and ten subjects with diabetes with BMI >20. The SBF response, above the quadriceps, was determined during a 6 minutes exposure to heat at 44°C. RESULTS: Even in young people, SBF after the stress of heat exposure was reduced in subjects with a high BMI. The effect of BMI was greatest in young people and lowest in older people and people with diabetes; in people with diabetes, BMI was a more significant variable than diabetes in causing impairment of blood flow to heat. BMI, for example, was responsible for 49% of the reduction in blood flow after stress heat exposure (R=-0.7) while ageing only accounted for 16% of the blood flow reduction (R=-0.397). CONCLUSIONS: These results would suggest the importance of keeping BMI low not only in people with diabetes to minimize further circulatory vascular damage, but also in young people to diminish long term circulatory vascular compromise.
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Envejecimiento/patología , Índice de Masa Corporal , Diabetes Mellitus/patología , Endotelio Vascular/patología , Adolescente , Adulto , Anciano , Diabetes Mellitus/fisiopatología , Endotelio Vascular/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculos/patología , Músculos/fisiopatología , Piel/irrigación sanguínea , Piel/fisiopatología , Temperatura Cutánea , Adulto JovenRESUMEN
To improve the catalytic performance and durability of Pt catalysts used for the methanol oxidation reaction (MOR) in direct methanol fuel cells (DMFCs), alloying of Pt with other transition metals such as Ru, Co, Ni, and Fe is considered an effective approach. Despite the significant progress made in the preparation of bimetallic alloys and their utilization for MOR, improving the activity and durability of the catalysts to make them commercially viable remains a stiff challenge. In this work, trimetallic Pt100-x(MnCo)x (16 < x < 41) catalysts were successfully synthesized via borohydride reduction followed by hydrothermal treatment at 150 °C. The electrocatalytic performance of the synthesized trimetallic Pt100-x(MnCo)x (16 < x < 41) catalysts toward MOR was studied using cyclic voltammetry and chronoamperometry. The results affirm that all Pt100-x(MnCo)x (16 < x < 41) alloys have superior MOR activity and durability as compared to bimetallic PtCo alloys and commercially available Pt/C (comm. Pt/C) catalysts. Among all the compositions studied, the Pt60Mn1.7Co38.3/C catalyst exhibited superior mass activity (1.3 and 1.9 times higher than those of Pt81Co19/C and comm. Pt/C, respectively) toward MOR. Furthermore, all the newly synthesized Pt100-x(MnCo)x/C (16 < x < 41) catalysts showed better CO tolerance when compared with comm. Pt/C. This improved performance of the Pt100-x(MnCo)x/C (16 < x < 41) catalyst can be attributed to the synergistic effect of Co and Mn on the Pt lattice.
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Microglia serve as resident immune cells in the brain, responding to insults and pathological developments. They have also been implicated in shaping synaptic development and regulation. The present study examined microglial cell density in a number of brain regions across select postnatal (P) ages along with the effects of valproic acid (VPA) on microglia density. Specifically, C57BL/6JCx3CR1+/GFP mice were examined for microglial cell number changes on P7, P14, P30, and P60 under baseline conditions and following 400 mg/kg VPA or saline. The prefrontal cortex (PFC), hippocampus and cerebellum were observed. Under control conditions, the results showed a shift in the number of microglia in these brain areas throughout development with a peak density in the hippocampus at P14 and an increase in PFC microglial numbers from P15 to P30. Interestingly, VPA treatment enhanced microglial numbers in a region-specific manner. VPA at P7 increased microglial cell number in the hippocampus and cerebellum whereas P14 VPA treatment altered microglial density in the cerebellum only. Cerebellar increases also occurred after VPA at P30, and were attended by an effect of increased numbers in the PFC. Finally, animals treated with VPA at P60 exhibited decreased microglia density in the hippocampus only. These results suggest rapid VPA-induced increases in microglial cell density in a developmentally-regulated fashion which differs across distinct brain areas. Furthermore, in the context of prior reports that early VPA causes excitotoxic damage, the present findings suggest early VPA exposure may provide a model for studying altered microglial responses to early toxicant challenge.
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Efectos Tardíos de la Exposición Prenatal , Ácido Valproico , Animales , Conducta Animal/fisiología , Cerebelo/patología , Hipocampo , Ratones , Ratones Endogámicos C57BL , Microglía/patología , Corteza Prefrontal , Efectos Tardíos de la Exposición Prenatal/patología , Ácido Valproico/toxicidadRESUMEN
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.
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Hipersensibilidad a las Drogas , Antígenos HLA-B , Humanos , Alelos , Antígenos HLA-B/genética , Hipersensibilidad a las Drogas/diagnóstico , Hipersensibilidad a las Drogas/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , ADN/genéticaRESUMEN
Delayed drug hypersensitivities are CD8+ T cell-mediated reactions associated with up to 50% mortality. Human leukocyte antigen (HLA) alleles are known to predispose disease and are specific to drug, reaction, and patient ethnicity. Pretreatment screening is recommended for a handful of the strongest associations to identify and prevent drug use in high-risk patients. However, an incomplete predictive value implicates other HLA-imposed risk factors, and low carriage of many identified HLA-risk alleles combined with the high cost of sequence-based typing has limited economic viability for similar recommendation of screening across drugs and health care systems. For mitigation, an expanding armory of low-cost polymerase chain reaction-based screens is being developed, and HLA-imposed risk factors are being discovered. These include (1) polymorphic variants of metabolic and endoplasmic reticulum aminopeptidase enzymes toward multiallelic screening with increased predictivity; (2) regulation by immune checkpoint inhibitors, enabling detolerized animal models of human disease; and (3) immunodominant T cell receptors (TCR) on clonally expanded CD8+ T cells. For the latter, HLA risk-restricted TCR provides immunogenomic strategies and samples from a single patient to identify novel HLA-risk associations in underserved minority populations, tissue-relevant effector biomarkers toward earlier diagnosis and treatment, and HLA-TCR-presented immunogenic structures to aid future drug development.
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Linfocitos T CD8-positivos , Hipersensibilidad a las Drogas , Hipersensibilidad a las Drogas/diagnóstico , Hipersensibilidad a las Drogas/genética , Antígenos HLA/genética , Humanos , Receptores de Antígenos de Linfocitos TRESUMEN
PURPOSE OF REVIEW: An update of the pharmacogenetic risk factors associated with T-cell-mediated delayed hypersensitivity reactions. RECENT FINDINGS: Recent HLA associations relevant to our understanding of immunopathogenesis and clinical practice include HLA-B∗13:01 with co-trimoxazole-induced SCAR, and HLA-A∗32:01 with vancomycin-DRESS, for which an extended HLA class II haplotype is implicated in glycopeptide antibiotic cross-reactivity. Hypoactive variants of ERAP1, an enzyme-trimming peptide prior to HLA loading, are now associated with protection from abacavir-hypersensitivity in HLA-B∗57:01+ patients, and single-cell sequencing has defined the skin-restricted expansion of a single, public and drug-reactive dominant TCR across patients with HLA-B∗15:02-restricted carbamazepine-induced SJS/TEN. More recent strategies for the use of HLA and other risk factors may include risk-stratification, early diagnosis, and diagnosis in addition to screening. SUMMARY: HLA is necessary but insufficient as a risk factor for the development of most T-cell-mediated reactions. Newly emerged genetic and ecological risk factors, combined with HLA-restricted response, align with underlying immunopathogenesis and drive towards enhanced strategies to improve positive-predictive and negative-predictive values. With large population-matched cohorts, genetic studies typically focus on populations that have been readily accessible to research studies, but it is now imperative to address similar risk in globally relevant and understudied populations.
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Hipersensibilidad a las Drogas , Farmacogenética , Síndrome de Stevens-Johnson , Linfocitos T/inmunología , Aminopeptidasas , Hipersensibilidad a las Drogas/diagnóstico , Hipersensibilidad a las Drogas/genética , Antígenos HLA-B/genética , Humanos , Antígenos de Histocompatibilidad MenorRESUMEN
Adverse drug reactions (ADRs) remain associated with significant mortality. Delayed hypersensitivity reactions (DHRs) that occur greater than 6 h following drug administration are T-cell mediated with many severe DHRs now associated with human leukocyte antigen (HLA) risk alleles, opening pathways for clinical prediction and prevention. However, incomplete negative predictive value (NPV), low positive predictive value (PPV), and a large number needed to test (NNT) to prevent one case have practically prevented large-scale and cost-effective screening implementation. Additional factors outside of HLA contributing to risk of severe T-cell-mediated DHRs include variation in drug metabolism, T-cell receptor (TCR) specificity, and, most recently, HLA-presented immunopeptidome-processing efficiencies via endoplasmic reticulum aminopeptidase (ERAP). Active research continues toward identification of other highly polymorphic factors likely to impose risk. These include those previously associated with T-cell-mediated HLA-associated infectious or auto-immune disease such as Killer cell immunoglobulin-like receptors (KIR), epistatically linked with HLA class I to regulate NK- and T-cell-mediated cytotoxic degranulation, and co-inhibitory signaling pathways for which therapeutic blockade in cancer immunotherapy is now associated with an increased incidence of DHRs. As such, the field now recognizes that susceptibility is not simply a static product of genetics but that individuals may experience dynamic risk, skewed toward immune activation through therapeutic interventions and epigenetic modifications driven by ecological exposures. This review provides an updated overview of current and proposed genetic factors thought to predispose risk for severe T-cell-mediated DHRs.
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The human leukocyte antigen (HLA) system is the most polymorphic in the human genome that has been associated with protection and predisposition to a broad array of infectious, autoimmune, and malignant diseases. More recently over the last two decades, HLA class I alleles have been strongly associated with T-cell-mediated drug hypersensitivity reactions. In the case of abacavir hypersensitivity and HLA-B*57:01, the 100% negative predictive value and low number needed to test to prevent a single case has led to a durable and effective global preprescription screening strategy. However, HLA associations are still undefined for most drugs clinically associated with different delayed drug hypersensitivity phenotypes, and an HLA association relevant to one population is not generalizable across ethnicities. Furthermore, while a specific risk HLA allele is necessary for drug-induced T-cell activation, it is not sufficient. The low and incomplete positive predictive value has hindered efforts at clinical implementation for many drugs but has provided the impetus to understand the mechanisms of HLA class I restricted T-cell-mediated drug hypersensitivity reactions. Current research has focused on defining the contribution of additional elements of the adaptive immune response and other genetic and ecologic risk factors that contribute to drug hypersensitivity risk. In this review we focus on new insights into immunological, pharmacological, and genetic mechanisms underpinning HLA-associated drug reactions and the implications for future translation into clinical care.
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Hipersensibilidad a las Drogas/genética , Antígenos HLA/genética , Inmunidad Adaptativa/genética , Inmunidad Adaptativa/inmunología , Alelos , Animales , Hipersensibilidad a las Drogas/inmunología , Antígenos HLA/inmunología , Antígenos HLA-B/genética , Antígenos HLA-B/inmunología , Humanos , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Farmacogenética/métodos , Linfocitos T/inmunologíaRESUMEN
Type B adverse drug reactions (ADRs) are iatrogenic immune-mediated syndromes with mechanistic etiologies that remain incompletely understood. Some of the most severe ADRs, including delayed drug hypersensitivity reactions, are T-cell mediated, restricted by specific human leukocyte antigen risk alleles and sometimes by public or oligoclonal T-cell receptors (TCRs), central to the immunopathogenesis of tissue-damaging response. However, the specific cellular signatures of effector, regulatory, and accessory immune populations that mediate disease, define reaction phenotype, and determine severity have not been defined. Recent development of single-cell platforms bringing together advances in genomics and immunology provides the tools to simultaneously examine the full transcriptome, TCRs, and surface protein markers of highly heterogeneous immune cell populations at the site of the pathological response at a single-cell level. However, the requirement for advanced bioinformatics expertise and computational hardware and software has often limited the ability of investigators with the understanding of diseases and biological models to exploit these new approaches. Here we describe the features and use of a state-of-the-art, fully integrated application for analysis and visualization of multiomic single-cell data called Visual Genomics Analysis Studio (VGAS). This unique user-friendly, Windows-based graphical user interface is specifically designed to enable investigators to interrogate their own data. While VGAS also includes tools for sequence alignment and identification of associations with host or organism genetic polymorphisms, in this review we focus on its application for analysis of single-cell TCR-RNA-Cellular Indexing of Transcriptomes and Epitopes by Sequencing (CITE)-seq, enabling holistic cellular characterization by unbiased transcriptome and select surface proteome. Critically, VGAS does not require user-directed coding or access to high-performance computers, instead incorporating performance-optimized hidden code to provide application-based fast and intuitive tools for data analyses and production of high-resolution publication-ready graphics on standard specification laptops. Specifically, it allows analyses of comprehensive single-cell TCR sequencing (scTCR-seq) data, detailing (i) functional pairings of α-ß heterodimer TCRs, (ii) one-click histograms to display entropy and gene rearrangements, and (iii) Circos and Sankey plots to visualize clonality and dominance. For unbiased single-cell RNA sequencing (scRNA-seq) analyses, users extract cell transcriptome signatures according to global structure via principal component analysis, t-distributed stochastic neighborhood embedding, or uniform manifold approximation and projection plots, with overlay of scTCR-seq enabling identification and selection of the immunodominant TCR-expressing populations. Further integration with similar sequence-based detection of surface protein markers using oligo-labeled antibodies (CITE-seq) provides comparative understanding of surface protein expression, with differential gene or protein analyses visualized using volcano plot or heatmap functions. These data can be compared to reference cell atlases or suitable controls to reveal discrete disease-specific subsets, from epithelial to tissue-resident memory T-cells, and activation status, from senescence through exhaustion, with more finite transcript expression displayed as violin and box plots. Importantly, guided tutorial videos are available, as are regular application updates based on the latest advances in bioinformatics and user feedback.
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BACKGROUND: A breast cancer biobank with retrospectively collected patient data and FFPE tissue samples was established in 2018 at Prashanti Cancer Care Mission, Pune, India. It runs a cancer care clinic with support from a single surgeon's breast cancer practice. The clinical data and tissue sample collection is undertaken with appropriate patient consent following ethical approval and guidelines. METHODS: The biobank holds clinical history, diagnostic reports, treatment and follow-up information along with FFPE tumor tissue specimens, adjacent normal and, in few cases, contralateral normal breast tissue. Detailed family history and germline mutational profiles of eligible and consenting patients and their relatives are also deposited in the biobank. RESULTS: Here, we report the first audit of the biobank. A total number of 994 patients with breast disease have deposited consented clinical records in the biobank. The majority of the records (80%, n = 799) are of patients with infiltrating ductal carcinoma (IDC). Of 799 IDC patients, 434 (55%) have deposited tumor tissue in the biobank with consent. In addition, germline mutation profiles of 84 patients and their family members are deposited. Follow-up information is available for 85% of the 434 IDC patients with an average follow-up of 3 years. CONCLUSION: The biobank has aided the initiation of translational research at our center in collaboration with eminent institutes like IISER Pune and SJRI Bangalore to evaluate profiles of breast cancer in an Indian cohort. The biobank will be a valuable resource to the breast cancer research community, especially to understand South Asian profiles of breast cancer.
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Bancos de Tejidos/normas , Neoplasias de la Mama/mortalidad , Estudios de Cohortes , Femenino , Humanos , India , Persona de Mediana Edad , Análisis de SupervivenciaRESUMEN
Evidence of autoimmune disease associated with hepatitis C virus (HCV)-infection has important clinical implications. A systematic profile of these autoantibodies in relevant clinical cohorts relative to healthy controls is needed to better inform current standard of care for chronic hepatitis C. Samples from an Australian cohort of chronic HCV-infected subjects (n=127) were tested for the presence of 19 diagnostic autoantibodies and compared with data available from a control cohort representing a general Caucasian population (n=198). Chronic HCV-infected individuals had a greater number of autoantibodies than controls (p<0.0001). Anti-nuclear antibodies (ANA) followed by anti-smooth muscle antibodies (SMA) were the most frequently detected autoantibodies within the HCV cohort and significantly more than in the control cohort (p<0.0001 and p=0.006, respectively). However, for most autoantibody assays the 95th percentile approximated the reference value for positivity. None of the autoantibodies were significantly associated with age or sex for the HCV cohort, except SMA positivity that was significantly higher in chronic HCV-infected male subjects (p<0.0001). Autoantibodies found in chronic HCV-infected subjects were commonly low positive and not disease-specific. Accordingly, general screening for autoimmunity in HCV-infected subjects should not be performed unless there is high clinical suspicion of an underlying autoimmune disease.
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Autoanticuerpos/sangre , Autoinmunidad/fisiología , Hepatitis C Crónica/inmunología , Adulto , Anciano , Anticuerpos Antinucleares/sangre , Femenino , Hepatitis C Crónica/sangre , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Abacavir hypersensitivity syndrome (ABC HSS) is strongly associated with carriage of human leukocyte antigen (HLA)-B*57:01, which has a 100% negative predictive value for the development of ABC HSS. However, 45% of individuals who carry HLA-B*57:01 can tolerate ABC. We investigated immune and non-immune related genes in ABC HSS (n = 95) and ABC tolerant (n = 43) HLA-B*57:01 + patients to determine other factors required for the development of ABC HSS. Assignment of phenotype showed that ABC HSS subjects were significantly less likely than tolerants to carry only ERAP1 hypoactive trimming allotypes (p = 0.02). An altered self-peptide repertoire model by which abacavir activates T cells is in keeping with observation that endoplasmic reticulum aminopeptidase 1 (ERAP1) allotypes that favour efficient peptide trimming are more common in ABC HSS patients compared to patients who tolerate ABC. Independently, non-specific immune activation via soluble cluster of differentiation antigen 14 (sCD14) may also influence susceptibility to ABC HSS.