Association of the polymorphisms rs179008 (TLR7), rs2004640 (IRF5), rs1800795 (IL-6) and rs2280788 (CCL5) with systemic lupus erythematosus in women of Mayan ethnicity from Yucatan.

Introduction: IFN-α is the main cytokine in SLE, and single nucleotide polymorphisms (SNP) in different genes could induce it. Aim: To determine the association of rs2004640 (IRF5), rs179008 (TLR7), rs1800795 (IL-6) and rs2280788 (CCL5) with SLE in Mexican women with Mayan ethnicity. Methods: DNA and RNA were isolated from the peripheral blood of 110 patients and 200 healthy control subjects. SNP genotyping and gene expression analysis of IRF5, TLR7, IL-6 and IFN-α were determined by real-time PCR and analyzed with SNP Stat, Stata 10.1 and Graph Pad Prism v5. Results: rs2004640, rs179008, and rs1800795 in both groups were according to Hardy-Weinberg equilibrium. Risk alleles rs179008T and rs2004640T frequencies were higher in controls (p = 0.015 and p = 0.028, respectively), whereas rs179008A frequency was higher in patients (p = 0.015). Allelic combination AGT frequency was higher in patients (p = 0.001). IL-6 rs1800795C > G and CCL5 rs2280788G > C frequencies did not show significant differences (p > 0.05), being rs2280788G (CCL5) monomorphic in controls. SLE patients showed higher TLR7, IRF5, IL6, and IFN-α mRNA levels. IRF5 expression was higher in SLE patients homozygous for rs2004640T (IRF5). Conclusion: This work showed the contribution of TLR7 and IRF5 in SLE pathogenesis in Mayan females from Yucatan.

The functional TNFAIP3 rs2230926T/G (Phe127Cys) variant confers risk to systemic lupus erythematosus in a Latin American population.

TNFAIP3 is a classical systemic lupus erythematosus (SLE)-associated risk locus identified by genome-wide association studies (GWASs) and replicated by candidate gene association studies primarily in Caucasians and Asians. However, in Latin American populations, its role on SLE susceptibility is not known. We conducted a case-control study to evaluate whether the TNFAIP3 rs2230926T/G (Phe127Cys) variant is associated with risk of developing SLE in a cohort of Mexican patients. The TNFAIP3 rs2230926T/G variant was analyzed in 561 patients with SLE and 499 control subjects, using TaqMan probes. We found that the G allele was associated with susceptibility to SLE under the allelic (OR 2.09, p = 0.005) and genotypic (OR 2.14, p = 0.004) models. In conclusion, our results show that TNFAIP3 rs2230926T/G is a risk factor for the development of SLE in the Mexican population.

Seguimiento de la actividad clínica y del daño orgánico acumulado en una cohorte de pacientes con lupus eritematoso sistémico de la península de Yucatán, México (1995-2016) / Follow-up of clinical activity and accumulated organic damage in a cohort of patients with Systemic Lupus Erythematosus from the Yucatán peninsula, México (1995-2016)

Introducción: El lupus eritematoso sistémico (LES) es una enfermedad autoinmune con severidad variable, frecuente en individuos hispanos y afroamericanos. Objetivo: Conocer la actividad clínica y el daño acumulado, así como la prevalencia e incidencia, en una cohorte dinámica de pacientes con LES de la península de Yucatán (1995 a 2016). Pacientes y métodos: Se analizaron 200 pacientes con LES, beneficiarios del servicio médico del Hospital Regional ISSSTE de Mérida, Yucatán, durante 22 años. Se evaluó la actividad de la enfermedad y el daño acumulado mediante la escala MEX-SLEDAI y SLICC-ACR-DI, respectivamente, y su correlación con variables clínicas y demográficas. Resultados: Se analizaron 185 pacientes mujeres y 15 hombres. Los índices promedio de actividad y daño acumulado durante el seguimiento fueron de 4,63 y 1,10, respectivamente. El índice de actividad se observó significativamente menor en las mujeres respecto de los hombres (4,36 vs. 7,43), y el daño acumulado no presentó diferencia por sexo. Las manifestaciones asociadas con mayor actividad fueron las mucocutáneas y articulares, y los órganos con mayor daño acumulado el musculoesquelético, el neurológico y el gonadal. Se encontró relación de los índices con el tiempo de evolución, las remisiones/reactivaciones y la actividad persistente. La mortalidad se relacionó con actividad persistente por complicaciones vasculares sistémicas e insuficiencia renal y hepática. La incidencia y prevalencia anual del LES calculada fue de 2,86% y 48,43% en la península de Yucatán. Conclusiones: Los pacientes presentaron actividad persistente, con reactivaciones leves a moderadas y daño acumulado más agresivo en hombres. La actividad clínica disminuye e incrementa el daño acumulado a mayor tiempo de evolución, con menor afección renal y mayor sobrevida, lo que sugiere un curso más benigno en la población de la península de Yucatán.(AU)

IntroductionSystemic lupus erythematosus (SLE) is an autoimmune with variable severity, common in Hispanic and African-American individuals.Objective: To know the clinical activity and the accumulated damage, as well as the prevalence and incidence, in a dynamic cohort of patients with SLE from the Yucatan Peninsula (1995-2016). Patients and methods: A cohort of 200 patients with SLE, medical service beneficiaries of the ISSSTE Regional Hospital of Mérida, Yucatán, was analyzed for 22 years. Disease activity and accumulated damage were evaluated using the MEX-SLEDAI scale and the SLICC-ACR-DI, respectively, and its correlation with clinical and demographic variables. Results: 185 female and 15 male patients were analyzed. Average accumulated damage and activity indices during follow-up were 4.63 and 1.10, respectively. The activity index was significantly lower in females compared to males (4.36 vs 7.43), and the accumulated damage did not present a difference by sex. The manifestations associated with greater activity were the mucocutaneous and articular ones, and the organs with the greatest accumulated damage were the musculoskeletal, neurological and gonadal. A relationship between the indices was found with the evolution time, remissions / reactivations, and persistent activity. Mortality was related to persistent activity due to systemic vascular complications and kidney and liver failure. The annual incidence and prevalence of SLE calculated was 2.86% and 48.43% in Yucatán Peninsula. Conclusions: The patients presented persistent activity, with mild to moderate reactivations, and accumulated damage more aggressive in men. The clinical activity decreases and increases the accumulated damage at a longer evolution time, with less kidney disease and greater survival, which suggests a more benign course in the population of the Yucatan Peninsula.(AU)

Rickettsia Vaccine Candidate pVAX1-OmpB24 Stimulates TCD4+INF-γ+ and TCD8+INF-γ+ Lymphocytes in Autologous Co-Culture of Human Cells.

BACKGROUND: In recent years, promising vaccination strategies against rickettsiosis have been described in experimental animal models and human cells. OmpB is considered an immunodominant antigen that is recognized by T and B cells. The aim of this study was to identify TCD4+INF-γ+ and TCD8+INF-γ+ lymphocytes in an autologous system with macrophages transfected with the vaccine candidate pVAX1-OmpB24. Lymphocytes and monocytes from 14 patients with Rickettsia were isolated from whole blood. Monocytes were differentiated into macrophages and transfected with the plasmid pVAX1-OmpB24 pVax1. Isolated lymphocytes were cultured with transfected macrophages. IFN-γ-producing TCD4+ and TCD8+ lymphocyte subpopulations were identified by flow cytometry, as was the percentage of macrophages expressing CD40+, CD80+, HLA-I and HLA-II. Also, we analyzed the exhausted condition of the T lymphocyte subpopulation by PD1 expression. Macrophages transfected with pVAX1-OmpB24 stimulated TCD4+INF-γ+ cells in healthy subjects and patients infected with R. typhi. Macrophages stimulated TCD8+INF-γ+ cells in healthy subjects and patients infected with R. rickettsii and R. felis. Cells from healthy donors stimulated with OmpB-24 showed a higher percentage of TCD4+PD1+. Cells from patients infected with R. rickettsii had a higher percentage of TCD8+PD-1+, and for those infected with R. typhi the larger number of cells corresponded to TCD4+PD1+. Human macrophages transfected with pVAX1-OmpB24 activated TCD4+IFN-γ+ and CD8+IFN-γ+ in patients infected with different Rickettsia species. However, PD1 expression played an important role in the inhibition of T lymphocytes with R. felis.

Follow-up of clinical activity and accumulated organic damage in a cohort of patients with systemic lupus erythematosus from the Yucatán Peninsula, Mexico (1995-2016).

INTRODUCTION: Systemic lupus erythematosus (SLE) is an autoimmune with variable severity, common in Hispanic and African-American individuals. OBJECTIVE: To know the clinical activity and the accumulated damage, as well as the prevalence and incidence, in a dynamic cohort of patients with SLE from the Yucatan Peninsula (1995-2016). PATIENTS AND METHODS: A cohort of 200 patients with SLE, medical service beneficiaries of the ISSSTE Regional Hospital of Mérida, Yucatán, was analysed for 22 years. Disease activity and accumulated damage were evaluated using the MEX-SLEDAI scale and the SLICC-ACR-DI, respectively, and its correlation with clinical and demographic variables. RESULTS: 185 female and 15 male patients were analysed. Average accumulated damage and activity indices during follow-up were 4.63 and 1.10, respectively. The activity index was significantly lower in females compared to males (4.36 vs 7.43), and the accumulated damage did not present a difference by sex. The manifestations associated with greater activity were the mucocutaneous and articular ones, and the organs with the greatest accumulated damage were the musculoskeletal, neurological and gonadal. A relationship between the indices was found with the evolution time, remissions/reactivations, and persistent activity. Mortality was related to persistent activity due to systemic vascular complications and kidney and liver failure. The annual incidence and prevalence of SLE calculated was 2.86% and 48.43% in Yucatán Peninsula. CONCLUSIONS: The patients presented persistent activity, with mild to moderate reactivations, and accumulated damage more aggressive in men. The clinical activity decreases and increases the accumulated damage at a longer evolution time, with less kidney disease and greater survival, which suggests a more benign course in the population of the Yucatan Peninsula.

High expression levels of circulating microRNA-122 and microRNA-222 are associated with obesity in children with Mayan ethnicity.

OBJECTIVES: High expression levels (HELs) of microRNA-122 (miR-122) or microRNA-222 (miR-222) have been associated with insulin resistance (IR), which leads to the development of obesity. The association between HELs of circulating miR-122 and miR-222 and the risk of obesity was evaluated in Mexican school-aged children, where childhood obesity is the primary cause of morbidity. METHODS: Anthropometric data, biochemical parameters, and caloric intake were obtained in 50 children with obesity and 49 children with normal weight. The expression of circulating miR-122 and miR-222 was measured by quantitative real-time polymerase chain reaction amplification. Data were analyzed using Student t test, Pearson correlation coefficient, associations with chi-square, and multiple linear and logistic regressions with SPSS software v.23. RESULTS: The mean relative expression for miR-122 and miR-222 was 0.33 and 5.65, respectively, for children with obesity and 0.22 and 3.16, respectively, for children with normal weight. The expression of miR-122 and miR-222 was 1.47 and 1.78-fold higher, respectively, in children with obesity (P = 0.001 and P = 0.025). HELs of both miR-122 and miR-222 were associated with body mass index (BMI), waist to height ratio (WHR), fat percentage, serum high-density lipid levels, triglycerides (TGs), and metabolic index (MI) (P < .001). CONCLUSIONS: The HELs of circulating miR-122 conferred a 3.85-fold increase in the risk for obesity, whereas the HELs of both miR-122 and miR-222 conferred a 3.11-fold increase in the risk for obesity, which were also associated with higher anthropometric or biochemical parameters, such as BMI, WHR, fat percentage, serum high-density lipid levels, TGs, and MI, in Mayan children.

ITGAM is a risk factor to systemic lupus erythematosus and possibly a protection factor to rheumatoid arthritis in patients from Mexico.

INTRODUCTION: ITGAM has consistently been associated with susceptibility to systemic lupus erythematosus (SLE) in many ethnically diverse populations. However, in populations with higher Amerindian ancestry (like Yucatan) or highly admixed population (like Mexican), ITGAM has seldom been evaluated (except few studies where patients with childhood-onset SLE were included). In addition, ITGAM has seldom been evaluated in patients with rheumatoid arthritis (RA). Here, we evaluated whether four single nucleotide polymorphisms (SNPs), located within ITGAM, were associated with SLE and RA susceptibility in patients from Mexico. METHODS: Our study consisted of 1,462 individuals, which included 363 patients with SLE (292 from Central Mexico and 71 from Yucatan), and 621 healthy controls (504 from Central Mexico and 117 from Yucatan). Our study also included 478 patients with RA from Central Mexico. TaqMan assays were used to obtain the genotypes of the four SNPs: rs34572943 (G/A), rs1143679 (G/A), rs9888739 (C/T), and rs1143683 (C/T). We also verified the genotypes by Sanger sequencing. Fisher's exact test and permutation test were employed to evaluate the distribution of genotype, allele, and haplotype between patients and controls. RESULTS: Our data show that all four ITGAM SNPs are significantly associated with susceptibility to SLE using both genotypic and allelic association tests (corrected for multiple testing, but not for population stratification). A second study carried out in patients from Yucatan, a southeastern part of Mexico (with a high Amerindian ancestry), also replicated SLE association with all four SNPs, including the functional SNP, rs1143679 (OR = 24.6 and p = 9.3X10-6). On the other hand, none of the four SNPs are significant in RA after multiple testing. Interestingly, the GACC haplotype, which carries the ITGAM rs1143679 (A) minor allele, showed an association with protection against RA (OR = 0.14 and p = 3.0x10-4). CONCLUSION: Our data displayed that ITGAM is a risk factor to SLE in individuals of Mexican population. Concurrently, a risk haplotype in ITGAM confers protection against RA.

The VEGFA -1154G/A polymorphism is associated with reduced risk of rheumatoid arthritis but not with systemic lupus erythematosus in Mexican women.

BACKGROUND: Levels of circulating vascular endothelial growth factor (VEGF) (a potent endothelial-cell-specific angiogenic factor) have been correlated with disease activity in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). In addition, several single nucleotide polymorphisms (SNPs), including the VEGFA -2578C/A, have been associated with RA in some populations. By contrast, the role of different VEGFA SNPs in the susceptibility to SLE has received little attention. Thus, the present study aimed to determine whether the VEGFA -2578C/A, -1154G/A and -634G/C polymorphisms confer risk or were associated with reduced risk of RA or SLE in a Mexican population. METHODS: The present study included 903 women from Mexico: 405 were patients with RA, 282 had SLE and 216 were healthy individuals. The genotypes were obtained with TaqMan probes. RESULTS: The data obtained in the present study suggest that the VEGFA -2578C/A and -634G/C polymorphisms are not risk factors for RA or SLE; however, VEGFA -1154G/A was associated with reduced risk in women with RA (odds ratio = 0.6, pc  = 0.0051) but not with SLE (odds ratio = 0.7, pc  = 0.13). CONCLUSIONS: The present study is the first to document an association between VEGFA -1154G/A and reduced risk in women with RA but not with SLE.

Serological and molecular analysis of parvovirus B19 infection in Mayan women with systemic lupus erythematosus in Mexico.

BACKGROUND: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that mainly affects women, characterized by the production of autoantibodies. Its causal agent is unknown, but the combination of environmental, hormonal and genetic factors may favor the development of the disease. Parvovirus B19 has been associated with the development of SLE, since it induces the production of anti-single stranded DNA antibodies. It is unknown whether PV-B19 infection is an environmental factor that trigger or reactivate SLE in the Mexican Mayan population. AIM: A preliminary serological and molecular study of PV-B19 infection in Mayan women with established SLE was done. METHODS: IgG and IgM anti PV-B19 were evaluated in 66 SLE patients and 66 control subjects, all women of Mayan origin. Viral DNA and viral load were analyzed by qPCR. RESULTS: Insignificant levels of IgM were observed in 14.3% (4/28) of the patients and 11.4% (4/35) of control subjects. IgG was detected in 82.1% (23/28) of the patients and 82.9% (29/35) of control subjects, but were significantly higher in patients. Viral DNA was found in 86.0% (57/66) of the patients and 81.0% (54/66) of control subjects. Viral load, quantified in 28/66 patients and 31/66 controls which were positive for IgM and IgG, was significantly higher in controls. CONCLUSION: The high prevalence of PV-B19 in Yucatan, and the presence of IgM, IgG, and viral load in Mayan women with established SLE suggest that PV-B19 infection could be an environmental factor to trigger or reactivate SLE.

ANTECEDENTES: Lupus eritematoso sistémico (LES) es una enfermedad sistemica autoinmune que afecta principalmente a las mujeres, caracterizada por la producción de autoanticuerpos. El agente causaal es desconocido. Pero la combinación de factores ambientales, hormonales y genéticos podría favorecer el desarrollo de la enfermedad. El parvovirus B19 se asoció con el desarrollo de LES, debido a que induce la producción de anticuerpos anti-cadena simple de DNA. Es desconocido si la infección PV-B19 es un factor ambiental que desencadena o reactiva LES en la población mexicana Maya. OBJETIVO: Se realizó un estudio serológico y molecular preliminar de la infección de PV-B19 en mujeres Mayas con LES. MÉTODOS: Se evaluó IgG and IgM anti PV-B19 en 66 pacientes con LES y 66 controles sanos, todas las mujeres fueron de origen Maya. DNAViral y la carga viral fueron analizadas por qPCR. RESULTADOS: Se determinaron niveles insignificantes de IgM en el 14.3% (4/28) de las pacientes y en el 11.4% (4/35) de los controles. IgG se detectó en el 82.1% (23/28) de los pacients y en el 82.9% (29/35) de los controles. Hubo un alta significancia en los pacientes con LES. DNA viral se encontró en el 86.0% (57/66) de los pacientes y en el 81.0% (54/66) de los controles. La carga viral se cuantifico en 28/66 pacientes y en 31/66 de los controles, la cual fueron positivos para IgM e IgG; fue significativamente mas alta en los controles. CONCLUSIÓN: La alta prevalencia de PV-B19 en Yucatan y la presencia de IgM, IgG y una carga viral en mujeres Mayas con LES sugiere que la infección con PV-B19 poria ser un factor ambiental que desencadene o reactive el LES.

Functional polymorphisms in pre-miR146a and pre-miR499 are associated with systemic lupus erythematosus but not with rheumatoid arthritis or Graves' disease in Mexican patients.

Recently, different microRNA (miRNA) gene polymorphisms have been evaluated in patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and Graves' disease (GD). In the present study, we examined three single-nucleotide polymorphisms (SNPs) located in the pre-miR-146a (rs2910164G/C), pre-miR-196a-2 (rs11614913C/T), and pre-miR-499 (rs3746444A/G) genes. Our study population included 900 Mexican patients with RA, SLE, or GD, as well as 486 healthy control individuals with no family history of inflammatory or autoimmune diseases. Genotyping was performed using TaqMan probes and a 5' exonuclease assay. None of the investigated SNPs were associated with RA or GD susceptibility under any genetic model (co-dominant, recessive, or dominant). Genotype and allele frequencies of the miR-196a-2 rs11614913C/T polymorphism were similar between SLE cases and controls. In contrast, the miR-146a rs2910164G/C and miR-499 rs3746444A/G polymorphisms were associated with SLE susceptibility. These SNPs were not associated with lupus nephritis (LN). Our results suggest that polymorphisms in miR-146a, miR-196a-2, and miR-499 are not associated with RA or GD susceptibility. This is the first report documenting that the miR-146a rs2910164G/C and miR-499 rs3746444 polymorphisms are associated with SLE susceptibility but not with LN.

Serological and molecular analysis of parvovirus B19 infection in Mayan women with systemic lupus erythematosus in Mexico / Análisis serológico y molecular de la infección por parvovirus B19 en mujeres mayas con lupus eritematoso sistémico en México

Abstract Background: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that mainly affects women, characterized by the production of autoantibodies. Its causal agent is unknown, but the combination of environmental, hormonal and genetic factors may favor the development of the disease. Parvovirus B19 has been associated with the development of SLE, since it induces the production of anti-single stranded DNA antibodies. It is unknown whether PV-B19 infection is an environmental factor that trigger or reactivate SLE in the Mexican Mayan population. Aim: A preliminary serological and molecular study of PV-B19 infection in Mayan women with established SLE was done. Methods: IgG and IgM anti PV-B19 were evaluated in 66 SLE patients and 66 control subjects, all women of Mayan origin. Viral DNA and viral load were analyzed by qPCR. Results: Insignificant levels of IgM were observed in 14.3% (4/28) of the patients and 11.4% (4/35) of control subjects. IgG was detected in 82.1% (23/28) of the patients and 82.9% (29/35) of control subjects, but were significantly higher in patients. Viral DNA was found in 86.0% (57/66) of the patients and 81.0% (54/66) of control subjects. Viral load, quantified in 28/66 patients and 31/66 controls which were positive for IgM and IgG, was significantly higher in controls. Conclusion: The high prevalence of PV-B19 in Yucatan, and the presence of IgM, IgG, and viral load in Mayan women with established SLE suggest that PV-B19 infection could be an environmental factor to trigger or reactivate SLE.

Resumen Antecedentes: Lupus eritematoso sistémico (LES) es una enfermedad sistemica autoinmune que afecta principalmente a las mujeres, caracterizada por la producción de autoanticuerpos. El agente causaal es desconocido. Pero la combinación de factores ambientales, hormonales y genéticos podría favorecer el desarrollo de la enfermedad. El parvovirus B19 se asoció con el desarrollo de LES, debido a que induce la producción de anticuerpos anti-cadena simple de DNA. Es desconocido si la infección PV-B19 es un factor ambiental que desencadena o reactiva LES en la población mexicana Maya. Objetivo: Se realizó un estudio serológico y molecular preliminar de la infección de PV-B19 en mujeres Mayas con LES. Métodos: Se evaluó IgG and IgM anti PV-B19 en 66 pacientes con LES y 66 controles sanos, todas las mujeres fueron de origen Maya. DNAViral y la carga viral fueron analizadas por qPCR. Resultados: Se determinaron niveles insignificantes de IgM en el 14.3% (4/28) de las pacientes y en el 11.4% (4/35) de los controles. IgG se detectó en el 82.1% (23/28) de los pacients y en el 82.9% (29/35) de los controles. Hubo un alta significancia en los pacientes con LES. DNA viral se encontró en el 86.0% (57/66) de los pacientes y en el 81.0% (54/66) de los controles. La carga viral se cuantifico en 28/66 pacientes y en 31/66 de los controles, la cual fueron positivos para IgM e IgG; fue significativamente mas alta en los controles. Conclusión: La alta prevalencia de PV-B19 en Yucatan y la presencia de IgM, IgG y una carga viral en mujeres Mayas con LES sugiere que la infección con PV-B19 poria ser un factor ambiental que desencadene o reactive el LES

The PTPN22 R263Q polymorphism confers protection against systemic lupus erythematosus and rheumatoid arthritis, while PTPN22 R620W confers susceptibility to Graves' disease in a Mexican population.

OBJECTIVE: The functional PTPN22 R620W polymorphism (rs2476601) is clearly associated with susceptibility to several autoimmune diseases (ADs). However, the PTPN22 R263Q polymorphism (rs33996649) has been scarcely explored in different ADs. Here we aimed to examine the associations of the PTPN22 R620W and R263Q polymorphisms with susceptibility to or protection against rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and Graves' disease (GD) among Mexican patients. METHODS: We conducted a case-control study including 876 patients (405 with SLE, 388 with RA, and 83 with GD) and 336 healthy control individuals. PTPN22 genotypes were determined using the TaqMan 5' allele discrimination assay. RESULTS: PTPN22 R620W was associated with GD susceptibility (OR 4.3, p = 0.004), but was not associated with SLE (OR 1.8, p = 0.19). We previously demonstrated that this polymorphism is associated with RA susceptibility (OR 4.17, p = 0.00036). Moreover, PTPN22 R263Q was associated with protection against SLE (OR 0.09, p = 004) and RA (OR 0.28, p = 0.045), but was not associated with GD. CONCLUSIONS: Our data provide the first demonstration that PTPN22 R620W confers GD susceptibility among Latin-American patients. Moreover, this is the second report documenting the association of PTPN22 R263Q with protection against SLE and RA.

Immunogenicity of OmpA and OmpB antigens from Rickettsia rickettsii on mononuclear cells from Rickettsia positive Mexican patients.

Background & objectives: The nature of the rickettsial antigens and the immune response generated by them, have been the subject of exhaustive research so that a suitable vaccine can be developed. Till date evaluations of Rickettsia rickettsii antigens that induce both humoral and cellular responses in animal models have only shown partial protection and short-term immunological memory. This study was aimed to evaluate the immune response induced by DNA plasmids generated from the OmpA and OmpB genes of R. rickettsii in peripheral blood mononuclear cells of rickettsial (sensitized) patients compared to healthy subjects. Methods: Plasmids OmpA-49, OmpB-15 and OmpB-24 were generated in the pVAX vector. Macrophages derived from the THP-1 cell line were transfected in vitro with the plasmids and were co-cultured with T-lymphocytes from sensitized subjects and healthy subjects to evaluate cell proliferation and cytokine production. Results: The OmpB-24 plasmid induced proliferative response in human lymphocytes, with production of IL-2, IFN-γ, IL-12p70, IL-6 and TNF-α, likely due to the presence of conserved epitopes among R. rickettsii, R. typhi and R. felis (differing from 1 to 3 amino acids) during the construction of the plasmids. Interpretation & conclusion: DNA sequences of rickettsial epitopes can be cloned into the pVAX vector. Constructed plasmids can generate a proliferative response and produce cytokines in vitro, in co-culture of transfected macrophages with sensitized human lymphocytes. Plasmid OmpB-24 proved to be the most immunogenic with respect to plasmids OmpA-49 and OmpB-15.

In situ cytokines (IL-4, IL-10, IL-12, IFN-γ) and chemokines (MCP-1, MIP-1α) gene expression in human Leishmania (Leishmania) Mexicana infection.

Crucial to the defense against Leishmania is the ability of the host to mount a cell-mediated immune response capable of controlling and/or eliminating the parasite. The composition of the cell populations recruited in the early phase of the infection seems to be essential for defining the infection outcomes. The signals that initiate and regulate the early immune response and local accumulation of cell subsets in the skin are poorly understood. We previously studied the in situ expression of cytokine genes in patients with localized cutaneous leishmaniasis (LCL) caused by Leishmania (Leishmania) mexicana. In the present study we examined in situ cytokine (IL-4, IL-10, IL-12, IFN-γ) and chemokine (MCP-1, MIP-1α) gene expression in L. (L.) mexicana active LCL lesions, and in the delayed type hypersensitivity (DTH) skin response to Leishmania antigen in subjects with healed lesion and subclinical infection. Data regarding cytokines were similar to previous studies in patients with active LCL. There were no significant differences in the profile of cytokine and chemokine gene expression in DTH from subjects with healed or subclinical infection. IL-12 gene expression detected in both groups was similar. High expression of MCP-1 was detected in all patients with active LCL. There was no difference in the level of MCP-1 expression between the healed lesion and the subclinical infection groups (p = 0.876). IL-12 and MCP-1 in the absence of IFN-γ might be playing a crucial role in infection outcomes at skin level.

Expression and activation of intracellular receptors TLR7, TLR8 and TLR9 in peripheral blood monocytes from HIV-infected patients / Expresión y activación de receptores intracelulares TLR7, TLR8 y TLR9 en monocitos de sangre periférica de pacientes infectados con VIH

Introduction: TLR´s play a role in host defense in HIV infection recognizing the viral DNA or RNA. Their activation induces a signaling pathway that includes the proteins MyD88, IRAK4, TRAF6 and the transcription factor NF-kBp65. Objective: To determine the expression of TLR7, TLR8 and TLR9, and activation of its signaling pathway in monocytes from patients infected with HIV. Methods. Expression of TLR7, TLR8 and TLR9 was determined in monocytes from HIV-infected patients (n= 13) and control subjects (n= 13), which were activated with specific ligands. The expression of MyD88 and NF-kBp65 were determined by flow cytometry; IRAK4 and TRAF6 were studied by immunoblotting. Results: No statistical difference was found in the expression of TLR7, 8 and 9 in monocytes from patients compared to controls, but we observed the non-significant increased expression of TLR9 in patients. The activation showed no significant difference in the expression of MyD88 and NF-kBp65 in patients when compared to controls, but were decreased in stimulated cells over non-stimulated cells. IRAK4 and TRAF6 were not detected. Conclusions: No statistical difference was observed in the expression of intracellular TLRs, MyD88 and NFkBp65 in monocytes from patients compared to controls. This was probably due to effective antiretroviral therapy being received at the time of study entry. Additional studies are needed under controlled conditions that include infected patients with and without ARVT, responders and non-responders, and work with different cell populations.

Introducción: En la infección por VIH los TLR juega un papel en la defensa del huésped al reconocer el ADN o ARN viral. Su activación induce la vía de señalización que incluye las proteínas MyD88, IRAK4, TRAF6 y el factor de transcripción NF-kBp65. Objetivo: Determinar la expresión del TLR7, TLR8 y TLR9, y activación de su vía de señalización en monocitos de pacientes infectados con VIH. Métodos: Se determinó la expresión de TLR7, TLR8 y TLR9 en monocitos de pacientes infectados con VIH (n =13) y sujetos control (n =13), se activaron con ligandos específicos y se determinó la expresión de MyD88 y NF-kBp65 por citometría de flujo. IRAK4 y TRAF6 fueron estudiadas por inmunoelectrotransferencia. Resultados: No se observó diferencia estadística en la expresión de TLR7, 8 y 9 en los monocitos de pacientes con respecto a los controles, pero observamos aumento no significante del TLR9 en los pacientes. La activación no mostró diferencia significativa en la expresión de MyD88 y NF-kBp65 en pacientes con respecto a los controles, pero se encontraron disminuidas en células estimuladas con respecto a las no estimuladas. IRAK4 y TRAF6 no se detectaron. Conclusiones: No se observó diferencia en la expresión de los TLR, ni en la expresión de MyD88 y NFkBp65, en monocitos de pacientes con respecto a los controles probablemente debido a la terapia antirretroviral recibida al momento del estudio. Se sugieren estudios con pacientes con y sin TARV, respondedores y no respondedores, y trabajar con diferentes poblaciones celulares.

Expression and activation of intracellular receptors TLR7, TLR8 and TLR9 in peripheral blood monocytes from HIV-infected patients.

INTRODUCTION: TLR´s play a role in host defense in HIV infection recognizing the viral DNA or RNA. Their activation induces a signaling pathway that includes the proteins MyD88, IRAK4, TRAF6 and the transcription factor NF-kBp65. OBJECTIVE: To determine the expression of TLR7, TLR8 and TLR9, and activation of its signaling pathway in monocytes from patients infected with HIV. Methods. Expression of TLR7, TLR8 and TLR9 was determined in monocytes from HIV-infected patients (n= 13) and control subjects (n= 13), which were activated with specific ligands. The expression of MyD88 and NF-kBp65 were determined by flow cytometry; IRAK4 and TRAF6 were studied by immunoblotting. RESULTS: No statistical difference was found in the expression of TLR7, 8 and 9 in monocytes from patients compared to controls, but we observed the non-significant increased expression of TLR9 in patients. The activation showed no significant difference in the expression of MyD88 and NF-kBp65 in patients when compared to controls, but were decreased in stimulated cells over non-stimulated cells. IRAK4 and TRAF6 were not detected. CONCLUSIONS: No statistical difference was observed in the expression of intracellular TLRs, MyD88 and NFkBp65 in monocytes from patients compared to controls. This was probably due to effective antiretroviral therapy being received at the time of study entry. Additional studies are needed under controlled conditions that include infected patients with and without ARVT, responders and non-responders, and work with different cell populations.

INTRODUCCIÓN: En la infección por VIH los TLR juega un papel en la defensa del huésped al reconocer el ADN o ARN viral. Su activación induce la vía de señalización que incluye las proteínas MyD88, IRAK4, TRAF6 y el factor de transcripción NF-kBp65. OBJETIVO: Determinar la expresión del TLR7, TLR8 y TLR9, y activación de su vía de señalización en monocitos de pacientes infectados con VIH. MÉTODOS: Se determinó la expresión de TLR7, TLR8 y TLR9 en monocitos de pacientes infectados con VIH (n= 13) y sujetos control (n= 13), se activaron con ligandos específicos y se determinó la expresión de MyD88 y NF-kBp65 por citometría de flujo. IRAK4 y TRAF6 fueron estudiadas por inmunoelectrotransferencia. RESULTADOS: No se observó diferencia estadística en la expresión de TLR7, 8 y 9 en los monocitos de pacientes con respecto a los controles, pero observamos aumento no significante del TLR9 en los pacientes. La activación no mostró diferencia significativa en la expresión de MyD88 y NF-kBp65 en pacientes con respecto a los controles, pero se encontraron disminuidas en células estimuladas con respecto a las no estimuladas. IRAK4 y TRAF6 no se detectaron. CONCLUSIONES: No se observó diferencia en la expresión de los TLR, ni en la expresión de MyD88 y NFkBp65, en monocitos de pacientes con respecto a los controles probablemente debido a la terapia antirretroviral recibida al momento del estudio. Se sugieren estudios con pacientes con y sin TARV, respondedores y no respondedores, y trabajar con diferentes poblaciones celulares.

Obtención de cultivo axénico de amastigotes de tres cepas de Leishmania (Leishmania) mexicana a partir de promastigotes aislados de pacientes con leishmaniasis cutánea localizada en México / Obtention of axenic cultivation of amastigotes of the three strains of Leishmania (Leishmania) mexicana using promastigotes isolated from patients with cutaneous leishmaniasis in Mexico

Introducción. La Leishmaniasis Cutánea Localizada, en la Península de Yucatán, es causada predominantemente por Leishmania (L.) mexicana. Las especies de Leishmania son parásitos intracelulares obligados dimórficos. Los promastigotes, formas flageladas y móviles, se replican y diferencian en el intestino del insecto vector. Los mastigotes, formas intracelulares inmóviles, viven dentro del fagolisosoma del macrófago huésped. Los amastigotes son más difíciles de obtener, debido a que se requieren ser aislados de tejidos y/o cultivos en líneas celulares de macrófagos. La alternativa es el cultivo axénico de formas de amastigotes. Material y métodos. El presente estudio describe la obtención de formas de amastigotes de tres cepas de Leishmania (L.) mexicana, (M/HOM/MX/94/VMC/663,M/HOM/MX/94/JM/758,M/HOM/MX/MX/95LPD/787), mediante la variación del pH y la temperatura de incubación en el medio de cultivo de Grace. Resultados. Los resultados mostraron un comportamiento diferente en cada cepa, determinado por la densidad celular y el porcentaje relativo de transformación. Los promastigotes de cada cepa se transformaron en más del 80 por ciento a formas de amastigotes al segundo día de incubación a pH 5.5 y temperatura de 35ºC. Por otro lado, la variación del pH, de 7.2 a 5.5 a 25ºC, permitió la transformación de promastigotes en metacíclicos. Conclusiones. La variación del pH y la temperatura de incubación permitió obtener las tres etapas de transformación del parásito (promastigotes, metacíclicos y amastigotes), los cuales podrán emplearse en futuros estudios bioquímicos e inmunológicos

Induction of macrophage killing of Leishmania donovani by human CD4+ T cell clones

Immunitary in leishmaniasis is mediated by T cells, but protective responses in humans have not been fully defined. In this study, the functional activity of CD4+ T cell clones derived from an immune individual was investigated to identify potentially protective responses. The T cells proliferated and produced interferon-gamma (IFN-gamma) in response to a soluble Leishmania donovani antigen extrac and live amastigotes. There was considerable variation in the anti-leishmanial activity of the T cell clones when they were co-cultured with L. donavani infected monocytes isolated from an HLA-DR,DQ mathced donor. All of the clones which demonstrated antigen specific reactivity by proliferation or cytokineproduction induced some dregee of inhibition of intracellular parasite replication, but only a few of the clones induced pronounced leishmanicidal activity. There was strong correlation between the level of amastigote-induced IFN-gamma secretion and anti-leishmanial activity. This approach anables the identification of potentially protective immune responses in humans at the clonal level, and offers a means for the identification of the relevant antigen(s)