MHC2TA rs4774C and HHV-6A active replication in multiple sclerosis patients.

BACKGROUND AND PURPOSE: In a previous report, a strong gene-environment interaction between human herpesvirus 6A (HHV6A) active replication and MHC2TA rs4774C was demonstrated. The objectives of this study were: (i) to reappraise the association that was found in the previous study; (ii) to evaluate if MS patients with minor allele C and HHV-6A active infection had different clinical behavior; and (iii) to analyze the possible association of MHC2TA rs4774C with Epstein-Barr virus (EBV). METHODS: A total of 149 MS patients were analyzed both at the MHC2TA locus and by HHV-6A status in serum. We studied a G/C polymorphism (rs4774) by a TaqMan Assay-on-Demand. HHV-6A genomes in serum were evaluated by quantitative PCR. A control group of 562 healthy Spanish individuals was included for comparative purposes in the genetic analyses. A battery of clinical data was collected for all the MS patients included in the study. RESULTS: (i) MHC2TA/HHV-6A interaction: we found the same strong association of the rs4774C allele with HHV-6A active replication than in the previous study (P = 0.0001). (ii) CLINICAL DATA: the two main statistical significant differences for MS patients with HHV-6A active infection and minor allele C were: (a) a significant number of them were not free of progression (EDSS = 0) 2 years after the diagnosis (P = 0.01); (b) only a third of them responded to interferon beta treatment (P = 0.05). CONCLUSIONS: This study has verified previous results about the strong gene-environment interaction between HHV6A active replication and MHC2TA rs4774C. Furthermore, a different clinical behavior for MS patients with HHV-6A active infection and minor allele C was found.

A functional variant in the CD209 promoter is associated with DQ2-negative celiac disease in the Spanish population.

AIM: To address the role of CD209 in celiac disease (CD) patients. Non-human leukocyte antigen (HLA) genetic factors in CD predisposition are poorly understood, and environmental factors like infectious pathogens may play a role. CD209 is a dendritic and macrophage surface molecule involved in pathogen recognition and immune activation. Recently, a functional variant in the promoter of the CD209 gene (-336A/G) has been shown to affect the transcriptional CD209 activity in vitro and it has been associated with a higher susceptibility to/or severity of infection. METHODS: The study population was composed of two case-control cohorts of 103 and 386 CD patients and 312 y 419 healthy controls as well as a panel of 257 celiac families. Genotyping for the -336A/G CD209 promoter polymorphism was performed using a TaqMan 5' allelic discrimination assay. HLA-DQ was determined by hybridization with allele specific probes. RESULTS: Initially, the case-control and familial studies did not find any association of the -336 A/G CD209 genetic variant with CD susceptibility. However, the stratification by HLA-DQ2 did reveal a significant association of CD209 promoter polymorphism in the HLA-DQ2 (-) group (carrier A vs GG in DQ2 (-) vs DQ2 (+) patients (P = 0.026, OR = 3.71). CONCLUSION: The -336G CD209 allele seems to be involved in CD susceptibility in HLA-DQ2 (-) patients. Our results might suggest a possible role of pathogens in the onset of a minor group of CD patients.

Influenza virus immunization effectivity in kidney transplant patients subjected to two different triple-drug therapy immunosuppression protocols: mycophenolate versus azathioprine.

BACKGROUND: Due to possible complications and treatment limitations, the prevention of influenza in renal transplant (RT) patients is highly indicated. METHODS: Forty-nine patients with a 1-year functioning RT subjected to two different immunosuppressive regimens and 37 healthy relatives (HR) were administered the anti-influenza vaccine as recommended for 1996 to 1997. Anti-influenza antibody, creatinine, and immunological markers were estimated at 1 and 3 months after vaccination. RESULTS: Three months after vaccination, 46.2% of the RT patients and 69% of the HR (P=0.06) showed protective antibody titers to influenza A (relative risk [RR]; 0.67; 95% confidence interval: 0.44-1.02). A total of 20.5% of the RT patients and 44.8% of the HR showed antibodies to influenza B (P=0.03). Despite these differences, the incidence of illness was similar. The immunosuppressive regimen had no effect on the antibody response. CONCLUSIONS: Although the RT patients showed a reduced antibody response, no negative effects on graft outcome were observed.

LOH at the APC/MCC gene (5Q21) in gastric cancer and preneoplastic lesions. Prognostic implications.

The APC/MCC gene (Familial Adenomatous Polyposis) at 5q21 plays a role in colon cancer carcinogenesis. LOH at this locus has also been described in gastric cancer and preneoplastic lesions. The APC locus has been recently related to a cell surface adhesion molecule and its alteration may favour metastatic dissemination. LOH at 5q21 has been associated with poor prognosis in other tumors such as lung cancer. Thirty-six gastric cancers were evaluated for LOH at 5q21 with 2 polymorphic markers from microdissected paraffin-embedded material. All tumors were classified by stage, histologic type, degree of differentiation and survival rates. In 4 cases, intestinal metaplasia cells in the adjacent mucosae were also microdissected. Six cases of moderate-severe gastric dysplasia were also added to the study. LOH was determined in 84% of the informative cases of GC, affecting both early and advanced stages of disease. Genomic instability was assessed in 5 cases, 3 of them associated with LOH. The only case of gastric cancer that did not show LOH or instability at 5q21 was a stage II, poorly differentiated intestinal carcinoma without evidence of recurrence after a 36 month follow-up period (the mean survival rate in our series was 28.3% at 36 months). We also found LOH in 2/6 dysplastic lesions and 1/4 intestinal metaplasias. Our data show that LOH at 5q21 is frequent in gastric cancer and is also present in intestinal metaplasia and dysplastic lesions. LOH at this locus is not a prognostic factor in GC in our study, due to the high incidence of LOH that we found.

[Selective IgA deficiency in systemic lupus erythematosus (author's transl)]. / Deficiencia selectiva de IgA en el lupus eritematoso sistémico.

The case of a 23 year-old female with a diagnosis of systemic lupus erythematosus associated to selective IgA deficiency is reported. The patient persistently had serum IgA levels below 0.05 mg/dl, while the remaining serum immunoglobulins were normal. No salivary IgA was detected, and the karyotype disclosed no abnormalities of the chromosome 18. In the in vitro immunological study a normal number of B and T lymphocytes was found, and decreased production of all surface immunoglobulins was observed.

[Lymphocyte subpopulations and surgery. The role of postoperative parenteral nutrition]. / Subpoblaciones linfocitarias y cirugía. Papel de la nutrición parenteral postoperatoria.

The effects of LCT-based lipid emulsions used in TPN on immune system remains controversial. In this prospective study we research the effects of three types of TPN on T-lymphocyte subsets and NK cells. 21 patients diagnosed because of upper gastrointestinal carcinoma (UGIC), and amenable of curative surgery were included in the study. TPN support was maintained 10 postoperative days at least. All patients received 35 non-proteic Kcal/KG BW/day. Group I (without lipid): received 100% of caloric intake (CI) by glucose. Group II (LCT): received 55% of CI by glucose and 45% by LCT at 20% emulsion. Group III (MCT/LCT): received 55% of CI by glucose and 45% by MCT/LCT at 20% mixture. T-lymphocyte subsets were determined by flow cytometry preoperatively and in first and tenth postoperative days. Our results suggest that patients diagnosed of UGIC present alterations of cellular immunity. These alterations are increased by the age and by surgical act. The changes found are independent of the type of TPN. LCT-based emulsions have similar effects on T-lymphocyte subsets that MCT/LCT-based emulsions.

[Genetics of autoimmune diseases]. / Genética de las enfermedades autoinmunes.

The publication of the human genome sequence this year was an important milestone in Biology. Autoimmune diseases arise through a complex interaction of genetics and environmental factors. They are influenced by more than one gene and do not exhibit a simple mode of inheritance. Some of the involved genes are thought to play a role in several autoimmune diseases whereas others seem to be specific for one of them. We have studied mainly genes located on the Major Histocompatibility Complex situated on the short arm of the 6th chromosome. This region is the most important genetic determinant for autoimmune diseases. It carries many genes playing a role in immune response and several have been observed to be associated with autoimmune diseases susceptibility. Although what has been published is just a draft of the human genome sequence, and a lot of work is needed to make sense of all these data and move into the study of gene function, the important technology breakthroughs of the last few years in genomics, proteomics and bioinformatics will speedup the study and results may come much earlier than could be imagined some years ago.

[Familial chronic mucocutaneous candidiasis. Study of 2 families]. / Candidiasis cutaneomucosa crónica familiar. Estudio de dos familias.

Four cases of familial mucocutaneous candidiasis corresponding to two families were studied. In two of the cases (Family I), there were lesions in the mouth, vaginal mucosa, nails, palms and soles, with no other associated infections. In the other two cases (Family II) there were oral (glossitis with macroglossia), genital and inguinal folds lesions, associated to frequent bacterial infections (recurring forunculosis , pneumonia). The immunological study in the four cases showed overlapping results: anti-candida circulating antibodies at high dilutions, a negative or weakly positive candidine a negative TTL to candida in some of the cases, and not other abnormalities in T. lymphocytes. All of the cases became sensitive to DNCB. In two of them, there were low figures of ferritin (Family II); however, no improvement was obtained with an iron treatment. There were no endocrinological abnormalities in any case. All of the cases were cured with ketoconazole in a few months, and no relapse was found six months after the end of the treatment in one of them. A follow up could not be performed on the other three cases.

The effects of purified mitogenic proteins (Pa-1 and Pa-2) from pokeweed on human T and B lymphocytes in vitro.

Purified proteins (Pa-1 and Pa-2) from pokeweed have been compared with commercial pokeweed mitogen (PWM-G) and other mitogens in their ability to stimulate human lymphocytes. With cultures of T and B cells separated from tonsil lymphocytes, thymidine uptake, blast transformation and immunoglobulin (Ig) synthesis have been measured. IgM and IgG was measured in supernates of stimulated cultures by radioimmunoassay. Pa-1, Pa-2 and PWM-G were found to be potent mitogens for unseparated tonsil lymphocytes or nylon column purified T cells. Pa-2 was found to be active at lower concentrations than Pa-1, and PWM-G was less potent than the purified mitogens. These three mitogens all stimulated unseparated lymphocytes to secrete large quantities of Ig (20-100 mug/ml) during 7 days in culture. With increasing amounts of mitogens severe decreases in immunoglobulin synthesis were observed at day 6 even with doses which were still optimal for stimulation of thymidine uptake at days 3 and 6. With purified B cells (less than 2% T cells) Pa-1 was the best mitogen for thymidine incorporation. However, the secretory response was very variable. In some experiments B cells did not secrete Ig in response to mitogens; in others Pa-1 was clearly more effective at stimulating secretion than Pa-2 or PWM-G and in some experiments B cells were stimulated by all three. In one experiment Pa-1 stimulated prolymphocytic leukaemia cells to blast transformation and the secretion of IgM. It is concluded that Pa-1, Pa-2 and PWM-G are much better activators of Ig synthesis in human cultures than either PHA or LPS and that Pa-1 is the most reliable B-cell stimulant of the three.

[Lymphocyte subpopulations in the evolution of brucellosis]. / Subpoblaciones linfocitarias en la evolución de la brucelosis.

We have sequentially studied for one year CD3+, CD4+, CD8+, CD11b+, and CD20+ lymphocyte subpopulations in 52 brucellosis patients whose diagnosis was confirmed by hemoculture. We observe at diagnosis a decreased percentage of CD4+ lymphocytes with an increase in CD8+ and inverted CD4+/CD8+ ratio, which was greater in patients with an evolution longer than 4 weeks (p less than 0.05) returning to normal very slowly. The percentage of monocytes was also increase at diagnosis (p less than 0.01) and at their second month CD3+ an CD20+ subpopulations did not suffer any changes during the follow up period. Patients were divided into two groups according to whether one or two anti-Brucella IgG peaks were observed in ELISA throughout the evolution. Patients in whom IgG titer decreased uninterruptedly, the inversion of the ratio during the first two months was greater, while those patients who suffered a relapse showed a simultaneous new decrease in CD4/CD8 ratio (p less than 0.05).

[Basal immunological parameters in a group of retirees]. / Parámetros inmunológicos basales en un grupo de viejos-jóvenes.

OBJECTIVES: a) establish the major immunological parameters for clinical use in a group of retirees; b) correlate its levels in relation to gender; c) assess the influence of some specific factors (substance abuse, diseases) on the analyzed parameters. MATERIAL AND METHODS: study period: 1990-1999; sample: 249; 102 men (M); 147 women (W). Median age: 67.03 (4.2) years. Analyzed immunological variables: total leukocytes, lymphocytes B, immunoglobulins (IgG, IgA and IgM), rheumatoid factor, lymphocytes subpopulations (CD4, CD8, ratio), natural killer, complement (C3 and C4) and delayed hypersensitivity tests. TECHNIQUES: flow cytometry (EPICS-Profile II) and Multitest IMC. STATISTICAL ANALYSIS: SPSS version 10.0.Results. Gender influence: leukocytes: M: 6,699.4 (1,615.0); W: 6,105.9 (1,470.5); p < 0,003; lymphocytes B (%): M: 9.4 (5.0); W: 11.3 (4.1); p < 0,003; IgG: M: 1,155.7 (320.0); W: 1,116.1 (257.8); p = 0,28, IgM: M: 112.7 (69.3); W: 136.8 (85.6); p < 0,01; IgA: M: 276.1 (114); W: 254.0 (122); p = 0,15; rheumatoid factor: M: 18.5 (6.6); W: 20.9 (18.8); p = 0,020; CD4 (%): M: 42.2 (9.7); W: 47.3 (9,1); p < 0.001; CD8 (%): M: 30.3 (10,8); W: 25.0 (10.2); p < 0,001; scores: M: 13.2 (7.4); 11m: 10.0 (7.2); p < 0,005. Influence of the substance abuse: smokers; lymphocytes B (%): 8.8 (3.4); No: 10.9 (4.7); p < 0.008; CD8 (%): smokers: 31.8 (13.2); No: 26.2 (9.9); p < 0.003; CD4/CD8 ratio: smokers: 1.6 (0.9); No: 2.0 (1.3); p < 0,05; scores: smokers: 14.3 (6.8); No: 10.8 (7.5); p < 0.02; alcoholism: lymphocytes B (%): 8.7 (2.5). No: 10.8 (4.7); p < 0.001; alcoholism: store: 16.9 (6.7); No: 10.7 (7.3); p < 0,001. Influence of the diseases: diabetes: CD4 (%): 49.4 (12.0); diabetics versus healthy: p = 0,05; CD4/CD8 ratio: 2.6 (2.5); diabetics versus healthy: p = 0,04; EPOC: CD8 (%): 32.9 (16,3); COPD versus healthy: p = 0,07; neoplasias NK (%): 17.1 (21.4); neoplasias versus healthy: p < 0,01. CONCLUSIONS. a) there are differences according to the gender in the parameters of normalcy of some variables; b) smoking and alcoholism alter the immunological test analyzed, and c) some chronic diseases influence the subpopulations of lymphocytes and the cutaneous test of delayed hypersensitivity.

[Purine nucleoside phosphorylase deficiency. Report of two cases]. / Déficit de purina nucleósido fosforilasa. Presentación de dos casos.

Two brothers with a PNP deficit are reported. The first case presented recurrent upper respiratory infections and died of a sepsis by pseudomonas. The second one was diagnosed when he was six months old and remains asymptomatic. Immunologic tests revealed a deficit of T cell mediated immunity. Treatment consisted on radiated erythrocytes transfusions because HLA compatible donors were not available.

Increased serum levels of IgA antibodies to hsp70 protein in patients with diabetes mellitus: their relationship with vascular complications.

We measured class-specific antibodies to the mycobacterial hsp70 protein in 67 patients with diabetes mellitus (27 type 1 and 40 type 2) with or without vascular complications. Using ELISA, the levels of IgG and IgM antibodies in the sera of diabetic patients did not significantly differ either from those of healthy control subjects or between both types of diabetes, regardless of gender, disease duration, HbA1 level, or type of vascular complication. In patients with type 2 diabetes, the mean serum IgA levels were significantly higher than those in their matched controls [274(71) mg/dl vs 208(88) mg/dl; P < 0.01]. In this group of patients, the IgA antibody titer was significantly correlated to the serum IgA level (r = 0.334; P < 0.01). Serological autoimmunity (IgG or IgM type) to hsp70 protein is common in both the normal and the diabetic population. The increased IgA levels and anti-hsp70 IgA titers in the sera of diabetics suggest a possible role of IgA in the pathogenesis of the vascular complications of diabetes mellitus.