Mannose-binding lectin gene variants and infections in patients receiving autologous stem cell transplantation.

BACKGROUND: Serious infections are common in patients undergoing autologous stem cell transplantation (ASCT) mainly because of the effects of immunosuppression. The innate immune system plays an important role in the defense against different infections. Mannose binding lectin (MBL) is a central molecule of the innate immune system. There are several promoter polymorphisms and structural variants of the MBL2 gene that encodes for this protein. These variants produce low levels of MBL and have been associated with an increased risk for infections. METHODS: Prospective cohort study. The incidence, severity of infections and mortality in 72 consecutive patients with hematologic diseases who underwent ASCT between February 2006 and June 2008 in a tertiary referral center were analyzed according to their MBL2 genotype. INNO-LiPA MBL2 was used for MBL2 gene amplification and genotyping. Relative risks (RR) (IC95%) as measure of association were calculated. Multivariate analysis was performed using logistic regression. RESULTS: A statistically significant higher number of fungal infections was found in patients with MBL2 variants causing low MBL levels (21.1%versus1.9%, p=0.016). In this MBL2 variant group infection was more frequently the cause of mortality than in the MBL2 wild-type group (p=0.05). Although not statistically significant, there was a higher incidence of major infections in the MBL2 variant group as well as a higher number of infections caused by gram-positive bacteria. CONCLUSIONS: Low-producer MBL2 genotypes were associated with an increased number of fungal infections in ASCT patients, which would suggest that MBL has a protective role against such infections. ASCT patients with MBL2 variant genotypes are more likely to die as a result of an infection.

Family-based association study of chromosome 6p12.2-p21.1 migraine locus.

BACKGROUND: One of the genome-wide linkage studies performed in migraine has yielded a significant linkage of migraine (with and without aura) with markers located at 6p12.2-21.1. This locus (named MIGR3) has not been replicated in the only genome-wide association scan study performed to date or in previous genome-wide linkage studies. OBJECTIVE: Our objective had been to replicate the MIGR3 locus performing a family-based association study. METHODS: A sample of 594 subjects belonging to 134 migraine families of diverse complexity underwent genotyping for the markers previously published as linked at 6p12.2-21.1 migraine locus. Family-based association test, under different models of inheritance, and also the model-free TDT analysis were performed. RESULTS: The best result was obtained with the D6S1650 marker under the additive model (rank [S observed] = 265.0; permuted P = .0006), using family-based association test program (HBAT subprogram). Similar results were obtained with the model-free TDTPHASE algorithm (P < .0001, corrected). Nominal significant P values were obtained for D6S1630, D6S452, and D6S257. After correction for multiple testing with the stratified false-discovery rate, all markers showed significant association (P < .0001). CONCLUSION: We corroborated that the MIGR3 locus at 6p12 is a genetic risk for migraine with and without aura.

Mannose-binding lectin promoter polymorphisms and gene variants in pulmonary tuberculosis patients from cantabria (northern Spain).

Mannose-binding lectin is a central molecule of the innate immune system. Mannose-binding lectin 2 promoter polymorphisms and structural variants have been associated with susceptibility to tuberculosis. However, contradictory results among different populations have been reported, resulting in no convincing evidence of association between mannose-binding lectin 2 and susceptibility to tuberculosis. For this reason, we conducted a study in a well genetically conserved Spanish population in order to shed light on this controversial association. We analysed the six promoter and structural mannose-binding lectin 2 gene variants in 107 patients with pulmonary tuberculosis and 441 healthy controls. Only D variant and HYPD haplotype were significantly more frequents in controls which would indicate that this allele could confer protection against pulmonary tuberculosis, but this difference disappeared after statistical correction. Neither the rest of alleles nor the haplotypes were significantly associated with the disease. These results would indicate that mannose-binding lectin promoter polymorphisms and gene variants would not be associated with an increased risk to pulmonary tuberculosis. Despite the slight trend of the D allele and HYPD haplotype in conferring protection against pulmonary tuberculosis, susceptibility to this disease would probably be due to other genetic factors, at least in our population.

[Study of celiac disease in the pediatric population of Cantabria (Spain) and first-degree relatives]. / Estudio de la enfermedad celíaca en la población pediátrica de Cantabria y sus familiares de primer grado.

BACKGROUND: Celiac disease (CD) is an autoimmune disease that affects genetically predisposed individuals. The HLA-DQ2 heterodimer is present in nearly 90% of patients while HLA-DQ8 is found in the remaining 10%. AIM: To study the characteristics of CD in pediatric patients in Cantabria and their first-degree relatives, with special emphasis on factors related to haplotype, serology, and forms of clinical presentation. PATIENTS AND METHODS: Eighty-six patients with CD and 215 first-degree relatives were HLA genotyped. Clinical, laboratory, immunologic, and histological data were obtained from all patients. RESULTS: Clinical presentation was classical in 95% of the patients and mono-symptomatic in the remaining 5%. Anti-gliadin antibodies (AGA) and anti-transglutaminase antibodies (ATGA) were positive in 95% of the patients and negative in 5% (all with IgA deficiency). DQ2 was found in 71% of the patients (homozygotes or heterozygotes) and DQ8 was found in 9.5%. No heterodimers of risk were found in 22%. CD was found in six relatives (three were positive for AGA and four were positive for ATGA). Forty-nine percent of the relatives carried the DQ2 heterodimer and 15% the DQ8 heterodimer; no heterodimers of risk were found in 40%. CONCLUSIONS: The most prevalent HLA found in patients with CD in the autonomous region of Cantabria was DQ2 (71%). This prevalence is clearly lower than that reported in other Spanish regions. The prevalence of CD among first-degree relatives was similar to that found in other studies performed in Spain (2.8%). Our data support the need for systematic study of the first-degree relatives of patients with CD.

Estudio de la enfermedad celíaca en la población pediátrica de Cantabria y sus familiares de primer grado / Study of celiac disease in the pediatric population of Cantabria (Spain) and first-degree relatives

Introducción: La enfermedad celíaca (EC) es una entidad mediada por fenómenos autoinmunes, que se presenta en sujetos susceptibles genéticamente. El 90% de los pacientes presenta el heterodímero HLA-DQ2, y el 10% restante suele presentar el HLA-DQ8. Objetivo: Estudiar las características de la EC en la población pediátrica de Cantabria y en sus familiares de primer grado, fundamentalmente en los aspectos relacionados con el haplotipo, la serología y sus formas de presentación clí nica. Pacientes y métodos: Estudio de 86 pacientes celíacos y 215 familiares de primer grado. Se recogieron datos clínicos, analíticos, inmunológicos, histológicos y de tipificación genómica. Resultados: El 95% de los caso se iniciaron con clínica clásica y el 5% eran formas monosintomáticas. Un 95% presentaba positividad a anticuerpos antigliadina (AAG) y antitransglutaminasa (AATG), y eran negativos el 5% (todos con déficit de IgA). Genotípicamente, un 71% eran portadores del DQ2 (incluidos los homocigotos y los heterocigotos), y un 9,5% del DQ8. Un 22% no presentaba heterodímero de riesgo. En el estudio familiar se hallaron 6 familiares con EC (3 AAG positivos y 4 AATG positivos). Del total, el 49% de los familiares portaba el DQ2, un 15% el DQ8, y un 40% no presentaba el heterodímero de riesgo. Conclusiones: El HLA más prevalente en nuestra comunidad fue el DQ2 (71%), claramente menor que lo publicado en nuestro medio. La prevalencia de EC en familiares de primer grado fue similar al resto de España (2,8%). Nuestros datos apoyan la necesidad del estudio sistemático en familiares de primer grado de pacientes celíacos

Background: Celiac disease (CD) is an autoimmune disease that affects genetically predisposed individuals. The HLA-DQ2 heterodimer is present in nearly 90% of patients while HLA-DQ8 is found in the remaining 10%. Aim: To study the characteristics of CD in pediatric patients in Cantabria and their first-degree relatives, with special emphasis on factors related to haplotype, serology, and forms of clinical presentation. Patients and methods: Eighty-six patients with CD and 215 first-degree relatives were HLA genotyped. Clinical, laboratory, immunologic, and histological data were obtained from all patients. Results: Clinical presentation was classical in 95% of the patients and mono-symptomatic in the remaining 5%. Anti-gliadin antibodies (AGA) and anti-transglutaminase antibodies (ATGA) were positive in 95% of the patients and negative in 5% (all with IgA deficiency). DQ2 was found in 71% of the patients (homozygotes or heterozygotes) and DQ8 was found in 9.5%. No heterodimers of risk were found in 22%. CD was found in six relatives (three were positive for AGA and four were positive for ATGA). Forty-nine percent of the relatives carried the DQ2 heterodimer and 15% the DQ8 heterodimer; no heterodimers of risk were found in 40%. Conclusions: The most prevalent HLA found in patients with CD in the autonomous region of Cantabria was DQ2 (71%). This prevalence is clearly lower than that reported in other Spanish regions. The prevalence of CD among first-degree relatives was similar to that found in other studies performed in Spain (2.8%). Our data support the need for systematic study of the first-degree relatives of patients with CD

Intracellular ATP concentrations of CD4 cells in kidney transplant patients with and without infection.

In the field of organ transplantation, overimmunosuppression is associated with severe side effects, such as infection, drug toxicity, and cancer, whereas underimmunosuppression is associated with acute rejection. Intracellular adenosine triphosphate (iATP) concentration following CD4 cell activation provides an assessment of cellular immune function to help monitor the immune status of immunosuppressed patients. This assay has shown to be the first post-transplant test related not only to the risk of acute rejection but also with the appearance of infection. The aim of our study was to compare the iATP concentrations of CD4 cells between healthy adults and kidney transplant recipients from a European population, analyzing the differences according to transplant clinical status. Samples from 81 kidney transplant patients who were admitted to our hospital over a nine-month period were drawn. T-cell activation was measured by determining the increase of iATP from CD4 cells. Results were compared with patient clinical status (rejection, infection, and stability). Three patients suffered an acute rejection episode and they were not included in the analysis (mean iATP concentration 247 +/- 87 ng/mL). iATP concentrations differed significantly between stable and infected patients (313 +/- 193 vs. 197 +/- 114 ng/mL; p = 0.008). iATP concentration values were not related to the length of admission, age, peak and current panel reactive antibodies, mismatches, leukocytes, weight, creatinine, days after transplantation and blood levels of cyclosporin, tacrolimus, and sirolimus. This assay measures global immune responses of CD4 T cells from a whole-blood sample, allowing for the assessment of the impact of immuno- suppressive drugs and of the patient's underlying clinical conditions. This assay identifies transplant patients at risk for infection or rejection, providing information which can guide immunosuppressive therapy.

Association of migraine and ESR1 G325C polymorphism.

Migraine is a genetically complex disorder in which sexual hormones influence the phenotype. ESR1 G594A polymorphism has been associated with migraine in Australians. We performed a case-control study with G594A and G325C polymorphisms to determine whether ESR1 is associated with migraine in our population. An association between G594A and migraine could not be demonstrated here. By contrast, we observed that the C325 allele conferred a 1.6 (95% confidence interval=1.1-2.4) higher risk for suffering from migraine in women than the G allele. Women carrying the C352C genotype were over 3 times more likely to suffer from migraine than those carrying the G325G genotype. Therefore, we conclude that ESR1 G325C polymorphism is associated with migraine in our population.

Sensitivity to bee venom antigen phospholipase A2: association with specific HLA class I and class II alleles and haplotypes in beekeepers and allergic patients.

Bee venom hypersensitivity is a clinical entity of outstanding importance because bee stings are a leading cause of mortality worldwide. Individuals with immediate-type bee venom hypersensitivity, beekeepers, and healthy controls were examined for HLA-DRB1, DQB1, and DQA1 alleles by sequence-specific oligonucleotide probe typing. Defined hypersensitivity to bee venom antigen phospholipase A2 (vbPLA2) is significantly associated with the presence of susceptible HLA class II alleles: DRB1*0101 (RR = 2.7, p < 3 x 10(-3)), DRB1*0103 (RR = 21.2, p < 7.5 x 10(-11)), DQA1*0101 (RR = 1.2, p < 38.52 x 10(-10)), and DQB1*0501 (RR = 4, p < 2.18 x 10(-10)). Some HLA class I alleles were also associated with risk to bee venom allergy: A*01 (RR = 2.4, p < 7.5 x 10(-4)), B*57 (RR = 35.1, p < 3.5 x 10(-7)), and B*5901 (p < 3.5 x 10(-5)), but they are probably of secondary significance. Three- (DRB1*0103-DQA1*0101-DQB1*0501) (RR = 21.24, p < 7.5 x 10(-11)) and five-loci (A*01-B*59-DRB1*0103-DQA1*0101-DQB1*0501) (p < 2.3 x 10(-6)) extended haplotypes are also significantly carried by vbPLA2 allergic patients. When HLA allele frequencies from patients are compared with those from beekeepers, only HLA-DRB1*0103 (RR = 11.7, p < 8.5 x 10(-5)) and HLA-DQA1*0101 (p < 0.02) were significantly increased in the former. These observations emphasize the importance of the DRB1*0103-DQA1*0101-DQB1*0501 haplotype as a strong candidate for susceptibility to vbPLA2 hypersensitivity, at least in our region.

Thymidylate synthase promoter tandem repeat and MTHFD1 R653Q polymorphisms modulate the risk for migraine conferred by the MTHFR T677 allele.

There is growing evidence that folate metabolism is involved in migraine pathophysiology, mainly in migraine with aura. Even though folate metabolism is regulated by a number of enzymes, only two functional polymorphisms have been tested in association studies with migraine. Here, we have explored the possible role in migraine of other folate-metabolizing enzymes which are in close interdependency with 5',10'-methylenetetrahydrofolate reductase analyzing functional polymorphisms of these enzymes in a case-control study. Individually, thymidylate synthase (TS), methenyltetrahydrofolate cyclohydrolase formyltetrahydrofolate synthase (MTHFD1), or methionine synthase (MS) polymorphisms did not modify the general risk for suffering migraine. Nevertheless, we observed a strong interaction between TS and MTHFR mutated genotypes, which increased over 8-fold the risk for experiencing aura among migraineurs; MTHFD1 and MTHFR mutated genotypes also increased together the risk for migraine in general (OR = 3.08; 95% CI = 1.3-7.4). We conclude that the pathogenetic role of the MTHFR T677 allele in migraine is modulated by functional polymorphisms of TS and MTHFD1.

Correlation between transcranial interleukin-6 gradient and outcome in patients with acute brain injury.

OBJECTIVE: This study was performed to examine both brain and systemic interleukin-6 (IL-6) release in patients with an acute brain injury (ABI), to study whether a correlation exists between the transcranial IL-6 gradient during the first days after injury and prognosis, and finally, to investigate the relationship between a nucleotide polymorphism at position -174 in the promoter of the gene encoding IL-6, IL-6 responsiveness, and clinical evolution. DESIGN: Prospective clinical investigation. SETTING: A 19-bed intensive care unit in a university hospital. PATIENTS AND METHODS: A total of 62 patients were followed up for 3 days after acute brain injury, and both their arterial and jugular IL-6 levels were measured serially and at the moment of brain death diagnosis. Genetic polymorphism of IL-6 was also determined in all patients. Data were correlated with those from score procedures for clinical severity. Neurologic outcome was graded according to the Glasgow Outcome Scale 6 months after injury. IL-6 levels and IL-6 genotyping was performed in control healthy individuals. MAIN RESULTS: There is a significant transcranial IL-6 gradient at admission and at the moment of brain death. The gradient is higher in those patients who evolved toward a fatal outcome during the first 6 months after injury (p <.001). There is significant correlation between the transcranial IL-6 gradient and the acute brain injury severity. CONCLUSIONS: IL-6 is elevated in patients with acute brain injury, and a significant relationship exits between the severity of acute brain injury and the transcranial IL-6 gradient at admission. It can be considered to be a prognosis marker at admission. When data at the moment of brain death are considered, venous IL-6 (p <.01) and the transcranial IL-6 gradient (p <.005) are significantly higher than at the time of admission. Although the IL-6 C allele is associated with significantly lower concentrations of IL-6, there was no correlation between low or high IL-6 responders and patient outcome.