The CD94/NKG2A inhibitory receptor educates uterine NK cells to optimize pregnancy outcomes in humans and mice.

The conserved CD94/NKG2A inhibitory receptor is expressed by nearly all human and ∼50% of mouse uterine natural killer (uNK) cells. Binding human HLA-E and mouse Qa-1, NKG2A drives NK cell education, a process of unknown physiological importance influenced by HLA-B alleles. Here, we show that NKG2A genetic ablation in dams mated with wild-type males caused suboptimal maternal vascular responses in pregnancy, accompanied by perturbed placental gene expression, reduced fetal weight, greater rates of smaller fetuses with asymmetric growth, and abnormal brain development. These are features of the human syndrome pre-eclampsia. In a genome-wide association study of 7,219 pre-eclampsia cases, we found a 7% greater relative risk associated with the maternal HLA-B allele that does not favor NKG2A education. These results show that the maternal HLA-B→HLA-E→NKG2A pathway contributes to healthy pregnancy and may have repercussions on offspring health, thus establishing the physiological relevance for NK cell education. VIDEO ABSTRACT.

Immunohistochemical analysis of chronic and recurrent dermatophytosis.

BACKGROUND: Dermatophytosis has assumed epidemic proportions with rising resistance, recalcitrance and recurrence, especially in tropical regions. While various factors contribute to high prevalence worldwide, yet little is known about the interactions between host defence mechanisms and dermatophytes, particularly in chronic and recalcitrant dermatophytosis. OBJECTIVES: We aimed to compare the population of various immune cells in specimens of chronic recurrent dermatophytosis and those with acute superficial dermatophytosis. METHODS: We investigated the density of various immune cells-Langerhans cells (CD1a+), macrophages (CD68+), dermal dendrocytes (Factor XIIIa+) in the skin of chronic dermatophytosis patients and those with successfully resolved lesions (controls). RESULTS: Langerhans cells were significantly decreased in the epidermis of patients, both in affected and unaffected areas in comparison with controls. In the dermis, however, no differences in the density of immune cells (macrophages and fibroblasts) were observed. LIMITATIONS: The limited sample size and immune cells evaluated could be expanded further in future research. CONCLUSION: These results indicate that the decreased number of Langerhans cells could be a potential risk factor for the development of chronic and recurrent dermatophytosis.

Clinico-mycological validation of dermatophytosis severity score and its correlation with patient-reported outcome measures.

BACKGROUND: Dermatophytosis impacts a significant portion of the global population. Recent shifts in the disease's presentation, severity and response to treatment, primarily due to emerging drug resistance, underscore the need for reliable assessment tools. The Dermatophytosis Severity Score (DSS) aims to standardise the evaluation of the disease's severity and monitor therapeutic responses. METHODS: In a cross-sectional pilot study, 25 adults with clinically diagnosed dermatophytosis were evaluated using the DSS. The study also aimed to establish the correlation of DSS with different stages of treatment, dermatophyte species and patient-reported outcomes. Participants were recruited from a dermatology outpatient clinic, and the DSS was applied at baseline, Weeks 4 and 8. The validity and reliability of the DSS were assessed using statistical measures, including Cronbach's alpha and intraclass correlation coefficient. RESULTS: The study comprised of a near-equal distribution of male (52%) and female (48%) patients, primarily within the age group of 20-39 years. A high recurrence rate of dermatophytosis (60%) was noted, and more than half of the patients (56%) had used topical steroids before presentation. The mean DSS significantly decreased from baseline to the final visit, mirroring the substantial reduction in the 5D itch scale and Dermatology Life Quality Index, with strong positive correlations observed between these measures. CONCLUSION: The DSS demonstrated high inter-rater reliability and internal consistency, indicating its utility as a reliable clinical tool for assessing dermatophytosis severity. The strong correlation of DSS with itch intensity and quality of life validates its role in patient-centered care. Continued use and further validation of the DSS are recommended to enhance dermatophytosis management and treatment outcomes.

Dermatophytoses Severity Score - A novel point-of-care scoring tool to assess the severity of dermatophytosis.

The rising prevalence of dermatophytosis in tropical countries coupled with drug resistance necessitates an objective scoring system to define the severity, monitor therapeutic response and predict prognoses. We attempted to establish and validate a new scoring system - Dermatophytoses Severity Score (DSS), for dermatophytoses affecting non-glabrous skin. A consensus group was convened to develop an objective and reproducible scoring system to describe the extent and severity of dermatophytosis of 200 consecutive patients with dermatophytosis. A second assessment entailed independent DSS scoring of the same patients by dermatologists and residents who were not part of the consensus group. The main outcome measured was index reliability, assessed in two steps, between the observers. A two-step assessment and DSS grading of 200 consecutive patients with clinically diagnosed dermatophytoses showed high reliability (Cronbach's α test and intraclass correlation coefficient). The DSS has demonstrated high reliability, and it could serve as a novel, reproducible and objective scoring tool for dermatophytosis.

Diversity of KIR genes and their HLA-C ligands in Ugandan populations with historically varied malaria transmission intensity.

BACKGROUND: Malaria is one of the most serious infectious diseases in the world. The malaria burden is greatly affected by human immunity, and immune responses vary between populations. Genetic diversity in KIR and HLA-C genes, which are important in immunity to infectious diseases, is likely to play a role in this heterogeneity. Several studies have shown that KIR and HLA-C genes influence the immune response to viral infections, but few studies have examined the role of KIR and HLA-C in malaria infection, and these have used low-resolution genotyping. The aim of this study was to determine whether genetic variation in KIR and their HLA-C ligands differ in Ugandan populations with historically varied malaria transmission intensity using more comprehensive genotyping approaches. METHODS: High throughput multiplex quantitative real-time PCR method was used to genotype KIR genetic variants and copy number variation and a high-throughput real-time PCR method was developed to genotype HLA-C1 and C2 allotypes for 1344 participants, aged 6 months to 10 years, enrolled from Ugandan populations with historically high (Tororo District), medium (Jinja District) and low (Kanungu District) malaria transmission intensity. RESULTS: The prevalence of KIR3DS1, KIR2DL5, KIR2DS5, and KIR2DS1 genes was significantly lower in populations from Kanungu compared to Tororo (7.6 vs 13.2%: p = 0.006, 57.2 vs 66.4%: p = 0.005, 33.2 vs 46.6%: p < 0.001, and 19.7 vs 26.7%: p = 0.014, respectively) or Jinja (7.6 vs 18.1%: p < 0.001, 57.2 vs 63.8%: p = 0.048, 33.2 vs 43.5%: p = 0.002, and 19.7 vs 30.4%: p < 0.001, respectively). The prevalence of homozygous HLA-C2 was significantly higher in populations from Kanungu (31.6%) compared to Jinja (21.4%), p = 0.043, with no significant difference between Kanungu and Tororo (26.7%), p = 0.296. CONCLUSIONS: The KIR3DS1, KIR2DL5, KIR2DS5 and KIR2DS1 genes may partly explain differences in transmission intensity of malaria since these genes have been positively selected for in places with historically high malaria transmission intensity. The high-throughput, multiplex, real-time HLA-C genotyping PCR method developed will be useful in disease-association studies involving large cohorts.

MIC and Upper Limit of Wild-Type Distribution for 13 Antifungal Agents against a Trichophyton mentagrophytes-Trichophyton interdigitale Complex of Indian Origin.

Dermatophytosis due to the Trichophyton mentagrophytes-Trichophyton interdigitale complex is being increasingly reported across India. Reports of therapeutic failure have surfaced recently, but there are no clinical break points (CBP) or epidemiological cutoffs (ECVs) available to guide the treatment of dermatophytosis. In this study, a total of 498 isolates of the T. mentagrophytes-interdigitale complex were collected from six medical centers over a period of five years (2014 to 2018). Antifungal susceptibility testing of the isolates was carried out for itraconazole, fluconazole, ketoconazole, voriconazole, luliconazole, sertaconazole, miconazole, clotrimazole, terbinafine, amorolfine, naftifine, ciclopirox olamine, and griseofulvin. The MICs (in mg/liter) comprising >95% of the modeled populations were as follows: 0.06 for miconazole, luliconazole, and amorolfine; 0.25 for voriconazole; 0.5 for itraconazole, ketoconazole, and ciclopirox olamine; 1 for clotrimazole and sertaconazole; 8 for terbinafine; 16 for naftifine; 32 for fluconazole; and 64 for griseofulvin. A high percentage of isolates above the upper limit of the wild-type MIC (UL-WT) were observed for miconazole (29%), luliconazole (13.9%), terbinafine (11.4%), naftifine (5.2%), and voriconazole (4.8%), while they were low for itraconazole (0.2%). Since the MICs of itraconazole were low against the T. mentagrophytes-interdigitale complex, this could be considered the choice of first-line treatment. The F397L mutation in the squalene epoxidase (SE) gene was observed in 77.1% of isolates with a terbinafine MIC of ≥1 mg/liter, but no mutation was detected in isolates with a terbinafine MIC of <1 mg/liter. In the absence of CBPs, evaluation of the UL-WT may be beneficial for managing dermatophytosis and monitoring the emergence of isolates with reduced susceptibility.

High-Resolution Genetic and Phenotypic Analysis of KIR2DL1 Alleles and Their Association with Pre-Eclampsia.

Killer-cell Ig-like receptor (KIR) genes are inherited as haplotypes. They are expressed by NK cells and linked to outcomes of infectious diseases and pregnancy in humans. Understanding how genotype relates to phenotype is difficult because of the extensive diversity of the KIR family. Indeed, high-resolution KIR genotyping and phenotyping in single NK cells in the context of disease association is lacking. In this article, we describe a new method to separate NK cells expressing allotypes of the KIR2DL1 gene carried by the KIR A haplotype (KIR2DL1A) from those expressing KIR2DL1 alleles carried by the KIR B haplotype (KIR2DL1B). We find that in KIR AB heterozygous individuals, different KIR2DL1 allotypes can be detected in both peripheral blood and uterine NK cells. Using this new method, we demonstrate that both blood and uterine NK cells codominantly express KIR2DL1A and KIR2DL1B allotypes but with a predominance of KIR2DL1A variants, which associate with enhanced NK cell function. In a case-control study of pre-eclampsia, we show that KIR2DL1A, not KIR2DL1B, associates with increased disease risk. This method will facilitate our understanding of how individual KIR2DL1 allelic variants affect NK cell function and contribute to disease risk.

Defining KIR and HLA Class I Genotypes at Highest Resolution via High-Throughput Sequencing.

The physiological functions of natural killer (NK) cells in human immunity and reproduction depend upon diverse interactions between killer cell immunoglobulin-like receptors (KIRs) and their HLA class I ligands: HLA-A, HLA-B, and HLA-C. The genomic regions containing the KIR and HLA class I genes are unlinked, structurally complex, and highly polymorphic. They are also strongly associated with a wide spectrum of diseases, including infections, autoimmune disorders, cancers, and pregnancy disorders, as well as the efficacy of transplantation and other immunotherapies. To facilitate study of these extraordinary genes, we developed a method that captures, sequences, and analyzes the 13 KIR genes and HLA-A, HLA-B, and HLA-C from genomic DNA. We also devised a bioinformatics pipeline that attributes sequencing reads to specific KIR genes, determines copy number by read depth, and calls high-resolution genotypes for each KIR gene. We validated this method by using DNA from well-characterized cell lines, comparing it to established methods of HLA and KIR genotyping, and determining KIR genotypes from 1000 Genomes sequence data. This identified 116 previously uncharacterized KIR alleles, which were all demonstrated to be authentic by sequencing from source DNA via standard methods. Analysis of just two KIR genes showed that 22% of the 1000 Genomes individuals have a previously uncharacterized allele or a structural variant. The method we describe is suited to the large-scale analyses that are needed for characterizing human populations and defining the precise HLA and KIR factors associated with disease. The methods are applicable to other highly polymorphic genes.

Novel KIR genotypes and gene copy number variations in northeastern Thais.

KIR (Killer Immunoglobulin-like Receptor) variants influence immune responses and are genetic factors in disease susceptibility. Using sequence-specific priming PCR, we have previously described the diversity of KIR genes in term of presence/absence in northeastern Thais (NETs). To provide additional resolution beyond conventional methods, quantitative PCR was applied to determine KIR copy number profiles. Novel expanded and contracted KIR copy number profiles were identified at cumulatively high frequencies. These all comprise haplotypes with duplication (6·9%) or deletion (2·7%) of KIR3DL1/S1 along with adjacent genes. Five expanded KIR profiles comprised haplotypes with duplications of KIR2DP1, 2DL1, 3DP1, 2DL4, 3DL1/S1 and 2DS1/4, whereas two contracted profiles contained only a single copy of KIR3DP1, 3DL1/S1 and 2DL4. Using a KIR haplotype prediction program (KIR Haplotype Identifier), 14% of NET haplotypes carried atypical haplotypes based on the gene copy number data.

A KIR B centromeric region present in Africans but not Europeans protects pregnant women from pre-eclampsia.

In sub-Saharan Africans, maternal mortality is unacceptably high, with >400 deaths per 100,000 births compared with <10 deaths per 100,000 births in Europeans. One-third of the deaths are caused by pre-eclampsia, a syndrome arising from defective placentation. Controlling placentation are maternal natural killer (NK) cells that use killer-cell immunoglobulin-like receptor (KIR) to recognize the fetal HLA-C molecules on invading trophoblast. We analyzed genetic polymorphisms of maternal KIR and fetal HLA-C in 484 normal and 254 pre-eclamptic pregnancies at Mulago Hospital, Kampala, Uganda. The combination of maternal KIR AA genotypes and fetal HLA-C alleles encoding the C2 epitope associates with pre-eclampsia [P = 0.0318, odds ratio (OR) = 1.49]. The KIR genes associated with protection are located in centromeric KIR B regions that are unique to sub-Saharan African populations and contain the KIR2DS5 and KIR2DL1 genes (P = 0.0095, OR = 0.59). By contrast, telomeric KIR B genes protect Europeans against pre-eclampsia. Thus, different KIR B regions protect sub-Saharan Africans and Europeans from pre-eclampsia, whereas in both populations, the KIR AA genotype is a risk factor for the syndrome. These results emphasize the importance of undertaking genetic studies of pregnancy disorders in African populations with the potential to provide biological insights not available from studies restricted to European populations.

Copy number variation leads to considerable diversity for B but not A haplotypes of the human KIR genes encoding NK cell receptors.

The KIR complex appears to be evolving rapidly in humans, and more than 50 different haplotypes have been described, ranging from four to 14 KIR loci. Previously it has been suggested that most KIR haplotypes consist of framework genes, present in all individuals, which bracket a variable number of other genes. We used a new technique to type 793 families from the United Kingdom and United States for both the presence/absence of all individual KIR genes as well as copy number and found that KIR haplotypes are even more complex. It is striking that all KIR loci are subject to copy number variation (CNV), including the so-called framework genes, but CNV is much more frequent in KIR B haplotypes than KIR A haplotypes. These two basic KIR haplotype groups, A and B, appear to be following different evolutionary trajectories. Despite the great diversity, there are 11 common haplotypes, derived by reciprocal recombination near KIR2DL4, which collectively account for 94% of KIR haplotypes determined in Caucasian samples. These haplotypes could be derived from combinations of just three centromeic and two telomeric motifs, simplifying disease analysis for these haplotypes. The remaining 6% of haplotypes displayed novel examples of expansion and contraction of numbers of loci. Conventional KIR typing misses much of this additional complexity, with important implications for studying the genetics of disease association with KIR that can now be explored by CNV analysis.

Influence of KIR gene copy number on natural killer cell education.

Natural killer (NK) cells are functionally tuned by education via killer cell immunoglobulin receptors (KIRs) interacting with HLA class I molecules. We examined the effect of KIR gene copy number variation on the education of human NK cells. The frequency of NK cells expressing a given KIR correlated with the copy number of that gene. However, coexpression of multiple copies from a single locus, or duplicated loci, was infrequent, which is in line with independent transcriptional regulation of each allele or copy. Intriguingly, coexpression of 2 KIR alleles, resulting in higher surface expression, did not lead to enhanced functional responses in vitro or to selective advantages during in vivo responses to cytomegalovirus infection, suggesting that receptor density does not influence NK education at the single cell level. However, individuals with multiple KIR gene copies had higher frequencies of responding cells, consistent with heightened overall responsiveness.

Evaluation of the Utility of the Edmonton Symptom Assessment System (revised) Scale on a Tertiary Palliative Care Unit.

AIM: The aim of this study was to evaluate the utility of the Edmonton Symptom Assessment System (ESAS-r) Scale on a tertiary palliative care unit. METHOD: There were 92 admitted patients who participated in the study; the scale was administered to those able to participate on day 1 (n = 35, 38 percent), on day 4 (n = 20, 21 percent), and weekly. Patient comfort level with the ESAS-r tool was assessed using a 5-point Likert scale (strongly disagree to strongly agree) on day 4. Nurses' and physicians' perceptions of clinical assessment pre- and postimplementation of the scale were surveyed using a 5-point Likert scale. RESULTS: Of the participating physicians, 75 percent (n = 3) found that the ESAS-r Scale did not enhance clinical assessment; the proportion of nurses with that response was 37.5 percent (n = 6). Among these care providers, 50 percent of the physicians (n = 2) and 62 percent of the nurses (n = 10) thought that the scale was burdensome to patients; but 60 percent of the patients who were able to complete the comfort-level survey (n = 12) indicated that they did not find the scale burdensome. CONCLUSION: Patient acuity, team expertise, perceived burden to patients, and time commitment all influenced staff's recommendation not to implement the ESAS-r tool on the palliative care unit.

A hybrid qPCR/SNP array approach allows cost efficient assessment of KIR gene copy numbers in large samples.

BACKGROUND: Killer Immunoglobulin-like Receptors (KIRs) are surface receptors of natural killer cells that bind to their corresponding Human Leukocyte Antigen (HLA) class I ligands, making them interesting candidate genes for HLA-associated autoimmune diseases, including type 1 diabetes (T1D). However, allelic and copy number variation in the KIR region effectively mask it from standard genome-wide association studies: single nucleotide polymorphism (SNP) probes targeting the region are often discarded by standard genotype callers since they exhibit variable cluster numbers. Quantitative Polymerase Chain Reaction (qPCR) assays address this issue. However, their cost is prohibitive at the sample sizes required for detecting effects typically observed in complex genetic diseases. RESULTS: We propose a more powerful and cost-effective alternative, which combines signals from SNPs with more than three clusters found in existing datasets, with qPCR on a subset of samples. First, we showed that noise and batch effects in multiplexed qPCR assays are addressed through normalisation and simultaneous copy number calling of multiple genes. Then, we used supervised classification to impute copy numbers of specific KIR genes from SNP signals. We applied this method to assess copy number variation in two KIR genes, KIR3DL1 and KIR3DS1, which are suitable candidates for T1D susceptibility since they encode the only KIR molecules known to bind with HLA-Bw4 epitopes. We find no association between KIR3DL1/3DS1 copy number and T1D in 6744 cases and 5362 controls; a sample size twenty-fold larger than in any previous KIR association study. Due to our sample size, we can exclude odds ratios larger than 1.1 for the common KIR3DL1/3DS1 copy number groups at the 5% significance level. CONCLUSION: We found no evidence of association of KIR3DL1/3DS1 copy number with T1D, either overall or dependent on HLA-Bw4 epitope. Five other KIR genes, KIR2DS4, KIR2DL3, KIR2DL5, KIR2DS5 and KIR2DS1, in high linkage disequilibrium with KIR3DL1 and KIR3DS1, are also unlikely to be significantly associated. Our approach could potentially be applied to other KIR genes to allow cost effective assaying of gene copy number in large samples.

Role of neutrophil-lymphocyte ratio as a prognostic marker in SJS/TEN patients.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe mucocutaneous reactions, usually to drugs, characterized by blistering and epithelial sloughing. SCORTEN is an established prognosticator index employed in SJS/TEN patients to evaluate their severity degree and mortality risk. Many studies done in the recent past have indicated that neutrophil-lymphocyte ratio (NLR) is related to disease activity in several dermatological diseases. Hence, this study has been performed to correlate the NLR of each patient with their respective SCORTEN values and assess whether NLR can be used as a prognostic marker in SJS/TEN. A single centre, retrospective, 4 year study was conducted at a tertiary care hospital. The required clinical and laboratory data were obtained from existing IP records of all cases of SJS/TEN disorders admitted in the last 4 years in our hospital between May 1st 2019 and April 30th 2023. The correlation coefficient and p value were analysed using the Spearman's rank correlation. The total sample size of the study was 22 patients. A female preponderance (59.1%) with an age range between 10 to 74 years was noted. Drugs were the main triggering factor in all the patients and antiepileptics were the most commonly implicated drug group. On statistical analysis a weak positive correlation (r = 0.182) between NLR and SCORTEN was noted, however p value was insignificant (p = 0.417). Further, mean ± SD of NLR was found to be higher in group II (patients with SCORTEN ≥ 3) as compared to group I (patients with SCORTEN < 3). On correlating NLR with each group separately, p value still remained insignificant. Elevation in NLR value reflects the systemic inflammation, but its role in predicting the severity of the disease needs further research involving larger sample size.

IADVL SIG Recalcitrant Dermatophytosis Position Statement on Super Bioavailable Itraconazole.

Itraconazole (ITZ) has been the mainstay of oral antifungal treatment for the current epidemic of recalcitrant dermatophytosis (RD) in India. Recently, a newer formulation of ITZ, super bioavailable itraconazole (SUBA-ITZ), is made available in the market by many pharmaceutical companies. It is important for dermatologists to understand the pharmacokinetic properties of SUBA-ITZ vis-a-vis conventional pellet formulation to use it effectively and safely. Indian Association of Dermatologists, Venereologists and Leprologists (IADVL) has established a special interest group for recalcitrant dermatophytosis (SIG-RD) to strengthen research, continuing medical education, and industry collaboration on the subject. This position statement on SUBA-ITZ by SIG-RD is an attempt to address current pieces of evidence and the position of this new formulation in the management of RD.

Killer cell immunoglobulin-like receptor (KIR) genes and their HLA-C ligands in a Ugandan population.

Killer cell immunoglobulin-like receptor (KIR) genes are expressed by natural killer cells and encoded by a family of genes exhibiting considerable haplotypic and allelic variation. HLA-C molecules, the dominant ligands for KIR, are present in all individuals and are discriminated by two KIR epitopes, C1 and C2. We studied the frequencies of KIR genes and HLA-C1 and C2 groups in a large cohort (n = 492) from Kampala, Uganda, East Africa and compared our findings with published data from other populations in sub-Saharan Africa (SSA) and several European populations. We find considerably more KIR diversity and weaker linkage disequilibrium in SSA compared to the European populations and describe several novel KIR genotypes. C1 and C2 frequencies were similar to other SSA populations with a higher frequency of the C2 epitope (54.9 %) compared to Europe (average 39.7 %). Analysis of this large cohort from Uganda in the context of other African populations reveals variations in KIR and HLA-C1 and C2 that are consistent with migrations within Africa and potential selection pressures on these genes. Our results will help understand how KIR/HLA-C interactions contribute to resistance to pathogens and reproductive success.

Determinants of place of death: a population-based retrospective cohort study.

BACKGROUND: As Canada's population ages, the location of end of life care (whether at home, extended care facility or hospital) may change depending on the location of death. We carried out a study to identify determinants of the place of death. METHODS: Data on deaths in British Columbia between 2004 and 2008 were obtained from the Vital Statistics Agency. Place of death was categorized into home, extended care facility, hospital or other. Logistic regression analyses were used to estimate the effects of age, sex, marital status, residence, place of birth and cause of death on place of death using adjusted odds ratios and 95% confidence intervals (95% CI). RESULTS: Of the 153,111 deaths in the study, 16.5% occurred at home, 29.0% in extended care, 51.0% in hospital and 3.5% occurred elsewhere. Male deaths were less likely to occur in extended care as compared with female deaths (odds ratio 0.73, 95% CI 0.71-0.75). Age (odds ratio 3.31, 95% CI 3.19-3.45 for those for ≥90 vs 70-79 years), marital status (odds ratio 1.42, 95% CI 1.38-1.47 widowed vs married), residence (odds ratio 0.80, 95% CI 0.76-0.83 rural vs Vancouver), place of birth (odds ratio 0.80, 95% CI 0.75-0.86 China vs Canada) and cause of death (odds ratio 3.91, 95% CI 3.69-4.13 dementia vs cancer) were also associated with death in extended care. CONCLUSIONS: Information on determinants of place of death can inform public health policy regarding care at the end of life and make resource allocation more efficient.