Diversity of KIR/HLA Genotypes and Their Association with Psoriasis Vulgaris in the Western Mexican Population.

NK and some T cell functions are regulated by the interaction between KIR and HLA molecules. Several studies have shown an association between activating KIR genes and the development of autoimmune diseases, including psoriasis vulgaris (PsV). Our objective was to determine the association between KIR/HLA genes and genotypes with PsV in the Western mestizo Mexican population. One hundred subjects diagnosed with PsV (SP) and 108 healthy subjects (HS) were genotyped for 14 KIR genes, HLA-Bw4, HLA-C1, and HLA-C2 by PCR-single specific primer (SSP). Positive associations of the KIR3DS1 gene (odds ratio (OR) 1.959, p = 0.021), G11 genotype (OR 19.940, p = 0.008), and KIR3DS1/HLA-ABw4 (OR 2.265, p = 0.009) were found with susceptibility to PsV. In contrast, the G1 genotype (OR 0.448, p = 0.031) and KIR3DL1/HLA-Bw4Ile80 (OR 0.522, p = 0.022) were negatively associated with susceptibility to this disease. These results suggest an implication of the KIR3DS1/HLA-ABw4 genotype in PsV pathology.

Distribution of KIR genes and KIR2DS4 gene variants in two Mexican Mestizo populations.

Killer immunoglobulin-like receptors (KIR) are transmembrane proteins that regulate NK and T cell subsets by recognizing HLA-I molecules as ligands. The KIR gene family consists of 16 genes, located at chromosome 19q13.4. KIR gene frequencies vary among populations. In Mexico, HLA and genetic ancestry studies show that Mestizo populations have different genetic backgrounds based on admixture with European, African, and Asian ancestry. This study aimed to evaluate the frequencies of KIR genes and genotypes in Guerrero and Jalisco, two Mexican Mestizo populations located in the south and the west of the country, respectively, and to compare these frequencies with those of other populations. KIR genotyping was performed by SSP-PCR. We observed that KIR gene frequencies were similar in both populations. There were 24 genotypes observed in Guerrero, 38 genotypes observed in Jalisco, 15 genotypes shared in both populations and 32 genotypes unique to one population or the other. In 10 individuals, nine novel genotypes were identified. KIR2DS4 gene variants showed significant differences: The KIR2DS4full gene was more common in Guerrero (p<0.0001), and the KIR2DS4del variant was more common in Jalisco (p<0.05). Differences in KIR2DS4 gene variants and genotypic profiles could be influenced by the genetic admixture in both regions.

KIR2DL2 and KIR2DS2 as genetic markers to the methotrexate response in rheumatoid arthritis patients.

CONTEXT: Disease Modifying Anti-Rheumatic Drugs (DMARDs) are aimed to interfere with rheumatoid arthritis (RA) progression and reduce the joint damage; however, not all patients respond alike. Killer-cell immunoglobulin-like receptors (KIR) and their ligands, human leucocyte antigen class I (HLA-I), have been associated with RA pathology; therefore, KIR and HLA genes may influence the treatment response. MATERIALS AND METHODS: We evaluated the association of KIR genotype and their ligands HLA-C genes with the response to DMARDs in RA patients. We included 69 patients diagnosed with RA and 82 healthy individuals as the reference group. KIR and HLA-C genotyping was performed using SSP-PCR. RA patients were assessed at baseline and under treatment at 6 and 12 months; subsequently classified as responders and non-responders in each time period. We evaluated the association between DMARD response and genes using statistical analysis by using Fisher exact test with Bonferroni correction; results were regarded as statistically significant at p < 0.05. RESULTS: Significant difference was observed in gene frequencies of patients and the reference group, KIR2DL2 was associated with RA (p = 0.031, OR = 2.119). We also observed an association between KIR2DS2 and the response to methotrexate (MTX), moreover, the combination KIR2DL2+/KIR2DS2+ was more frequent in responders to MTX (p = 0.043). DISCUSSION AND CONCLUSIONS: In our results, responders and non-responders to DMARDs showed KIR2DS2 and KIR2DL2 different gene frequencies, therefore, these genes could be used as response predictors to DMARDs treatment. Thus, these genes were also associated with disease severity, as well as the treatment response possibly by the immunoregulatory function of NK cells.

University students' knowledge and attitudes towards leprosy.

INTRODUCTION: Patients with leprosy may be affected psychologically and socially by the negative attitude of society toward leprosy, caused by widespread ignorance and prevailing stereotypes surrounding the disease. This study aimed to determine the knowledge and attitudes toward leprosy among students at the University of Guadalajara. METHODOLOGY: This descriptive cross-sectional study included 1,300 students over 18 years of age from various Thematic University Centres in Guadalajara. Students' degree subjects included the health sciences, humanities, exact sciences (i.e., chemistry, physics), arts, biological-agricultural sciences, and administration. Students were randomly selected regardless of gender and all students were enrolled in either the first, second, or third year of their undergraduate studies. RESULTS: Overall, students showed an intermediate level of knowledge of leprosy. Results showed that 67% correctly responded that leprosy is an infectious disease, 64% knew of the presence of skin lesions, and 60% knew that a microbe causes the disease. Furthermore, 45% correctly responded that leprosy is a disease associated with poverty and 40% responded that leprosy is disabling. Only 31% stated that leprosy is curable. Negative attitudes were evident regarding the question of employing a leprosy patient (57%) and having a leprosy patient as a spouse or partner (30%). DISCUSSION: The results revealed that there is insufficient knowledge of and poor attitudes toward leprosy among students at the University of Guadalajara. It is necessary to improve current health education measures by using updated educational strategies to reduce the stigma of leprosy and the segregation of leprosy patients and their families.