Lymphomagenesis-related gene expression in B cells from sustained virological responders with occult hepatitis C virus infection.

The expression of activation-induced cytidine deaminase, B-aggressive lymphoma, cyclin D1 and serine/threonine kinase 15 genes, among others, is increased in B cells from patients with chronic hepatitis C virus (HCV) infection. It is unknown whether the level of expression of these genes in B cells is increased in patients with hepatitis C who have achieved a sustained virological response (SVR) but who have persistent, detectable HCV RNA, so-called occult infection. Eighty-three patients who achieved and SVR, 27 with detectable HCV and 56 without detectable HCV RNA, 28 chronic hepatitis C patients and 32 healthy controls were studied. RNA was extracted from B cells, and gene expression levels were measured by RT-PCR. Patients with chronic HCV and those who achieved an SVR (with and without persistent low-level HCV RNA) showed a statistically significant higher expression compared to healthy controls, of activation-induced cytidine deaminase (P = 0.004, P < 0.001 and P = 0.002, respectively), B-aggressive lymphoma (P < 0.001, P = 0.001 and P = 0.006) and cyclin D1 (P = 0.026, P = 0.001; P = 0.038). For activation-induced cytidine deaminase patients with an SVR and 'occult infection' had a statistically significantly higher expression level than patients with and SVR without 'occult infection' (P = 0.014). The higher expression levels found for activation-induced cytidine deaminase, together with other genes indicates that these B lymphomagenesis-related genes are upregulated following HCV therapy and this is more marked when HCV can be detected in PBMCs.

Incidence of the C104R TACI mutation in patients with primary antibody deficiency

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Differential expression pattern of microRNAs in CD4+ and CD19+ cells from asymptomatic patients with systemic lupus erythematosus.

OBJECTIVE: The aim of this study was to investigate the pattern of microRNA (miRNA) expression in CD19+ and CD4+ cells from asymptomatic patients with systemic lupus erythematosus (SLE). METHODS: A screening of the expression of 377 miRNAs was performed in human CD4+ and CD19+ cells isolated from the peripheral blood by using a TaqMan Human MicroRNA Array. Validation of differential expression pattern of those was performed using TaqMan assays in these cell populations obtained from a larger cohort of patients and controls. RESULTS: According to the screening assays, three miRNAs were differentially expressed (p value <0.1) in cell populations from both patients and controls: hsa-miR-143, hsa-miR-224 and hsa-miR-576-5p for CD4+ cells, and hsa-miR-10a, hsa-miR-31 and hsa-miR-345 for CD19+ cells. After validation, significant differences (p value <0.05) were confirmed only for hsa-miR-143 and hsa-miR-224 in CD4+ cells and for hsa-miR-10a and hsa-miR-345 in CD19+ cells. In all cases, the miRNAs were over expressed in SLE patients compared with healthy donors. CONCLUSIONS: Our results support a different pattern of miRNA expression in SLE patients.

Influence of donor specific HLA antibodies detected by Luminex in kidney graft survival: a multivariate analysis.

Some studies have demonstrated the clinical relevance of a positive virtual crossmatch in graft survival; nevertheless, other donor and recipient variables influence the outcome of the transplant. The aim of this study was to investigate the relevance of a positive virtual crossmatch in the graft survival performing a multivariate analysis including other pretransplant variables. A total of 879 deceased kidney transplantations were included. Univariate and multivariate analyses were performed using Cox regression model. After performing the multivariate analysis, a positive virtual crossmatch against class I (adjusted HR 6.613; 95% CI 3.222-13.573), class II (adjusted HR 2.419; 95% CI 1.170-5.002) and class I+II (adjusted HR 5.717; 95% CI 1.925-16.975) detected by single antigen Luminex was the variable conferring the greatest relative risk of graft loss. A positive virtual crossmatch predicts a worse kidney graft survival even after correction by other variables and therefore, transplantation of patients with positive virtual crossmatches should be avoided.

Cellular immune responses and occult infection in seronegative heterosexual partners of chronic hepatitis C patients.

It is unknown whether hepatitis C virus (HCV)-specific cellular immune responses can develop in seronegative sexual partners of chronically HCV-infected patients and whether they have occult infection. Thirty-one heterosexual partners of patients with chronic HCV were studied, fifteen of them with HCV transmission risks. Ten healthy individuals and 17 anti-HCV seropositive patients, without viremia, were used as controls. Virus-specific CD4+ and CD8+ T-cell responses were measured by flow cytometry against six HCV peptides, situated within the nonstructural (NS) proteins NS3, NS4 and NS5, through intracellular detection of gamma interferon (IFN-γ) or interleukin 4 (IL-4) production and CD69 expression. Sexual partners had a higher production of IFN-γ and IL-4 by CD4+ cells against NS3-p124 (P = 0.003), NS5b-p257 (P = 0.005) and NS5b-p294 (P = 0.012), and CD8+ cells against NS3-p124 (P = 0.002), NS4b-p177 (P = 0.001) and NS3-p294 (P = 0.004) as compared with healthy controls. We observed elevated IFN-γ production by CD4+ T cells against NS5b-p257 (P = 0.042) and NS5b-p294 (P = 0.009) in the sexual partners with HCV transmission risks (sexual, professional and familial altogether) than in those without risks. RNA was extracted from peripheral blood mononuclear cells (PBMC), and detection of HCV-RNA positive and replicative (negative) strands was performed by strand-specific real-time PCR. In four sexual partners, the presence of positive and negative HCV- RNA strands in PBMC was confirmed. Hence, we found an HCV-specific cellular immune response as well as occult HCV infection in seronegative and aviremic sexual partners of chronically HCV-infected patients.

Association of Toll-like receptor 10 and susceptibility to Crohn's disease independent of NOD2.

Impaired innate inflammatory response has a key role in the Crohn's disease (CD) pathogenesis. The aim of this study was to investigate the possible role of the TLR10-TLR1-TLR6 gene cluster in CD susceptibility. A total of 508 CD patients (284, cohort 1 and 224, cohort 2) and 576 controls were included. TLR10-TLR1-TLR6 cluster single-nucleotide polymorphisms genotyping, NOD2 mutations and TLR10 mRNA quantification were performed using TaqMan assays. Nucleotide-binding oligomerization domain containing 2 (NOD2) and Toll-like receptor (TLR) loci interaction was analyzed by logistic regression and multifactor-dimensionality reduction (MDR). Entropy-based analysis was used to interpret combination effects. One TLR10 haplotype (TLR10(GGGG)) was found associated with CD susceptibility in both cohorts, individuals with two copies had approximately twofold more risk of CD susceptibility than individuals having no copies (odds ratio=1.89, P-value=0.0002). No differences in the mRNA levels were observed among the genotypes. The strongest model for predicting CD risk according to the MDR analysis was a two-locus model including NOD2 mutations and TLR10(GGGG) haplotype (P(c)<0.0001). The interaction gain attributed to the combination of both genes was negative (IG=-2.36%), indicating redundancy or independent effects. Our results support association of the TLR10 gene with CD susceptibility. The effect of TLR10 would be independent of NOD2, suggesting different signaling pathways for both genes.

Donor-specific antibody detection: comparison of single antigen assay and Luminex crossmatches.

Luminex bead-based assays are routinely used in the study of anti-human leukocyte antigen (HLA) donor-specific antibodies (DSA). Single antigen (SA) assays use beads coated with recombinant antigens whereas Luminex crossmatch (Xm-DSA) tests consist of beads coated with isolated donor-specific HLA molecules. The aim of this study was to compare these techniques used to detect DSA. A total of 24 sera recognizing different HLA class I (seven anti-HLA-A and seven anti-HLA-B) as well as class II (seven anti-HLA-DR and three anti-HLA DQ) specificities by complement dependent cytotoxicity were included in the study. These sera were used undiluted and in serial dilutions to perform both class I and II SA and Xm-DSA assays. In the case of Xm-DSA the same serum was checked with different lysates. A total of 42 lysates were used to perform a total of 61 crossmatches: 42 to detect anti-class I and 19 to detect anti-class II antibodies. The maximum positive dilution was higher for SA in 76% of the class I and in 90% of the class II crossmatches. Those cases with a higher sensitivity of the Xm-DSA could not be explained by a larger number of antigen targets.

C7 deficiency and meningococcal infection susceptibility in two spanish families.

In this work, we report the genetic basis of C7 deficiency in two different Spanish families. In family 1, by using exon-specific polymerase chain reaction and sequencing, a recently described mutation was found in homozygosity in the patient; a single base change in exon 15 (C2107T) leading to a stop codon that causes truncation of the C-terminal portion of C7 (Q681X). Patient's father, mother and sister were heterozygous for this mutation. Interestingly, patient's parents were not related. In family 2, a new single base mutation in exon 2 (G90A), leading to a stop codon that causes the premature truncation of C7 (W8X), was found in the patient, mother and sister 1. Additionally, patient 2, her father and sisters, displayed a missense mutation in exon 9 (G1135C) resulting in a change of aminoacid (G357R). Although sister 1 bore the same mutations in the C7 gene that patient 2, she remains asymptomatic. Because both mutations were found in the patient and her sister, we analyse other defence mechanisms such as FcgammaR polymorphisms as well as mannose-binding lectin alleles (MBL2 gene) and MBL levels. Results showed that both siblings bore identical combinations of FcgammaR allotypes and different MBL2 alleles, exhibiting patient 2 a MBL-insufficient genotype. Normal MBL levels were found in patient 1 and in two previously studied C7-deficient siblings, suggesting the involvement of other mechanisms of immunity distinct of FcgammaR variants and the MBL pathway, for the absence of meningococcal recurrent infections in certain C7-deficient individuals.

Clinical relevance and prevalence of polymorphisms in CYP3A5 and MDR1 genes that encode tacrolimus biotransformation enzymes in liver transplant recipients.

OBJECTIVES: To study the prevalence and clinical significance of polymorphisms in the CYP3A5 and MDR1 genes in liver transplant patients and their donors; to determine the relative importance of genes from the donor and the recipient; to assess the relationship of polymorphisms with the variability of concentration/dose of tacrolimus for optimization and individualization regimens. MATERIALS AND METHODS: This prospective study included 53 liver transplant recipients who received tacrolimus de novo. CYP3A5 and MDR1 gene polymorphisms were identified in the donors and recipients using polymerase chain reaction. We collected indicator variables of graft function and the patient for 3 months after the transplantation: days 0, 1, 3, 7, 14, 30, 60, and 90. RESULTS: The frequencies of CYP3A5 polymorphisms were: 90.6% (G/G), 9.4% (G/A) and 0% (A/C) in donors and 88.7% (G/G), 11.3% (G/A), and 0% (A/A) in recipients. For the MDR1 gene, they were: 26.4% (C/C), 50.9% (C/T), and 22.6% (T/T) in donors and 17.0% (C/C), 71.7% (C/T), and 11.3% (T/T) in recipients. In the early days after transplant, G/A recipients from G/A donors did not reach the minimum drug levels. Between days 30 and 60, G/G recipients from G/A donors required higher tacrolimus doses. G/G recipients (CYP3A5) from C/T donors (MDR1) had a lower frequency of renal dysfunction, the same rejection rate, and a higher rate of diabetes than the other groups. CONCLUSIONS: For CYP3A5, the presence of the A allele appeared to be related to greater requirements for tacrolimus in the early days after transplantation. Pharmacogenetics combined with pharmacodynamics may be a useful tool to adjust the concentration of tacrolimus depending on the absorption by the individual patient.

Evaluation of third generation anti-CCP antibodies in the diagnosis of rheumatoid arthritis from undifferentiated polyarthritis after 4 years of follow-up.

OBJECTIVES: Rheumatoid arthritis (RA) is a complex pathology to identify at an early stage. A large number of patients with recent onset polyarthritis (ROP) do not usually fulfil the ACR criteria for diagnosis of the disease and are classified as having undifferentiated polyarthritis. The aim of this study is to verify with certainty the diagnosis of patients whose illness has not been classified after four years of follow-up, and correlate their actual status with the levels of anti-cyclic citrullinated peptide (anti-CCP) antibodies and rheumatoid factor (RF) found. METHODS: After one year of follow-up, 56 patients from a total of 322, included from January 2002 in the ROP Unit, did not meet ACR criteria for any rheumatic disease. The anti-CCP antibodies and RF levels were determined in the initial clinical assessment. RESULTS: After four years of follow-up, 12 new diagnoses were made in the 56 patients with undifferentiated polyarthritis: 3 seronegative RA, 8 seropositive RA and 1 psoriatic arthritis. The anti-CCP antibodies levels were positive for 5 of these 12 patients (median anti-CCP 228.6 U/mL), and all were RF positive. Six of the 7 anti-CCP antibodies negative patients were diagnosed of RA (3 seropositive and 3 seronegative for RF) and 1 was diagnosed of psoriatic arthritis (anti-CCP antibodies negative and RF positive). Forty-four patients still displayed undifferentiated polyarthritis and were RF negative. CONCLUSION: A positive result for RF and anti-CCP antibodies in patients who do not meet the ACR diagnostic criteria could be a useful indicator of the presence of future RA.

PTPN22 C1858T polymorphism and the outcome of hepatitis C virus infection.

The outcome of chronic hepatitis C virus infection varies, depending on viral and host factors. Those mechanisms involved in the control of the innate and adaptive response could have an influence on the outcome of infection. The PTPN22 gene encodes an intracellular lymphoid-specific phosphatase (Lyp) with a lymphocyte activating downregulatory effect. A single-nucleotide polymorphism (SNP) C1858T located on this gene has been associated with autoimmune diseases and bacterial infections. The aim of this study was to assess whether the PTPN22 C1858T polymorphism is related to the outcome of hepatitis C viral infection. A total of 69 patients with spontaneous viral clearance (SVC), 281 patients with chronic hepatitis C (CHC), and 1036 individuals not infected with hepatitis C (NIC) were included in this study. Patients with CHC were stratified according to Scheuer score of hepatic fibrosis from F0-F2 (n = 200) and F3-F4 (n = 81), and according to their response to therapy in patients with sustained responses (SR; n = 103) and non-sustained response (NSR; n = 104). Genotyping of the C1858T polymorphism was performed using TaqMan probes. No statistically significant differences in the distribution of PTPN22 C1858T polymorphism were observed upon comparison of patient group with the NIC group. Also, when the different patient groups were compared to one another, no statistically significant differences were detected: the SVC with the CHC group (10.2% versus 12.5%; p = 0.6), the F0-F2 with the F3-F4 group (11.5% versus 14.8%; p = 0.5), and the NSR with the SR group (11.5% versus 14.6%; p = 0.4). Our results do not support a major role of this polymorphism of the PTPN22 gene in the outcome of chronic hepatitis C virus infection in the Spanish population.

A recent onset inflammatory polyarthritis register in Spain: factors that predict remission.

OBJECTIVE: To identify baseline variables that predict remission at 1 year in patients with recent onset inflammatory polyarthritis (IP). METHODS: We prospectively studied 167 patients aged >or=16 years with a 4-week to 12-month history of swelling of >or=2 joints. At baseline, no patient had previously received corticosteroids or disease-modifying anti-rheumatic drugs (DMARDs). To adjust for differences in baseline variables associated with the type of treatment given (a surrogate marker of disease severity), we used regression analysis. The classification probability of treatment thus obtained was entered, along with other significant baseline variables, in a second separate regression analysis to identify variables that predicted remission (no swollen joints). RESULTS: Frequency of remission was 50.9% at 1 year. In the first regression analysis, variables associated with treatment with DMARDs or DMARDs and corticosteroids versus corticosteroids alone included age, morning stiffness, swollen joint count (SJC), disease severity according to the patient, and rheumatoid factor (RF) level; the strongest association was for higher SJC. In the second regression analysis, the model that best predicted remission (correct in 70.1% of cases) included age, tender joint count (TJC), erythrocyte sedimentation rate (ESR), RF, total Sharp score, disease severity according to the physician, and the 1987 American Rheumatism Association (ARA) criteria for rheumatoid arthritis (RA); the strongest association was for failure to meet these criteria. The model's sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve were 70.6%, 70.9%, and 75.4%, respectively. CONCLUSION: Although we identified some predictors of remission, no model accurately predicted remission at 1 year in this cohort.

Caspase 7 influences susceptibility to rheumatoid arthritis.

OBJECTIVE: The aim of this study was to investigate the possible role of the caspase 7 (CASP7) in susceptibility to rheumatoid arthritis (RA). METHODS: Genotyping of three single nucleotide polymorphisms (SNPs) of the CASP7 gene: rs11593766 (G/ T), rs2227310 (C/G) and rs2227309 (G/A) was performed in a total of 906 RA patients and 528 matched healthy controls using TaqMan assays. All the subjects were of Spanish Caucasian origin. A relative quantification of mRNA encoding the non-functional variant of procaspase 7 (isoform beta) vs functional isoforms was performed in total RNA from 32 healthy individuals using real-time PCR. RESULTS: Only the rs2227309 SNP was found to be associated with susceptibility to RA. Frequency of the G allele was significantly higher among RA patients [overall frequency of the G allele 74.0% in cases vs 68.4% in controls, P = 0.001, Odds ratio (OR) = 1.32, 95% Confidence intervals (95% CI) 1.11-1.56] and a higher frequency of GG homozygous individuals was found in the RA patient group (overall frequency of GG genotype 56.0% in cases and 46.4% in controls, P = 0.0005, OR = 1.47, 95%CI 1.18-1.83). A statistically significant deviation was observed to compare the relative expression of the procaspase 7 isoform beta in samples from individuals stratified according their rs2227309 genotypes (AA + AG: 1.36 +/- 0.55, n = 19, vs GG: 2.35 +/- 0.74, n = 13; P = 0.0002). CONCLUSION: Our results support involvement of the CASP7 gene in the susceptibility to RA. The higher production of the no functional variant of CASP7 by individuals with a particular genotype could be the basis of this association.

CCL2-2518 A/G and CCR2 190 A/G do not influence the outcome of hepatitis C virus infection in the Spanish population.

AIM: To assess whether CCL2 or interactions between this chemokine and its receptor (CCR2) are associated with outcomes of chronic hepatitis C and with responses to antiviral therapy. METHODS: Two hundred and eighty-four patients with chronic hepatitis C and 193 non-infected matched controls were included in this study. Patients were categorized according to their Scheuer score of hepatic fibrosis as F0-F2 (n = 202) or F3-F4 (n = 82) and according to their response to anti-Hepatitis C virus (HCV) therapy as sustained response (SR, n = 101) or non-sustained response (NSR, n = 98). Genotyping of the -2518 (A/G) CCL2 was performed using PCR-RFLP, genotyping of the 190 (A/G) CCR2 using a PCR-ARMS system, and genotyping of the rs3138042 (G/A) CCR2 using Taqman probes. RESULTS: Univariate analyses identified 4 parameters (infection duration time, viral genotype, gender and AST levels) that tended to influence fibrosis and 7 parameters (CCL2G, CCL2ACCR2A, viremia levels, fibrosis stage, viral genotype, infection duration time and AST levels) that significantly influenced or tended to influence response to treatment. Multivariate analysis identified gender and AST levels as parameters that independently influenced fibrosis stage and viral genotype and infection duration time were the two parameters that independently influenced response to treatment. CONCLUSION: Our results indicate that the mutations studied in the gene pair CCL2/CCR2 do not play a major role in the outcome and response to treatment for HCV infection in the Spanish population.

Asporin repeat polymorphism in rheumatoid arthritis.

BACKGROUND: Asporin belongs to a family of proteins associated with the cartilage matrix. OBJECTIVE: To investigate the role of the functional polymorphism consisting of an aspartic acid (D) repeat polymorphism located in the ASPN gene in the susceptibility to and clinical outcome of rheumatoid arthritis. METHODS: A total of 803 Spanish Caucasian patients with rheumatoid arthritis and 904 controls of the same ethnic origin and matched for age and sex were included in the study. The asporin D repeat polymorphism was genotyped using polymerase chain reaction with a fluorescent primer. RESULTS: No significant differences were detected in the distribution of the 10 alleles found in our population on comparing patients with rheumatoid arthritis with control groups. Nevertheless, individuals bearing D14 produced rheumatoid factor more often than the rest (85.7% v 72.1%, p = 0.006, odds ratio (OR) = 2.35, 95% confidence interval 1.21 to 4.50), and the mean (SD) onset age was higher in the group of individuals bearing D13 (50.09 (13.94)) compared with the rest (47.21 (14.31)), although the difference did not reach significance (p = 0.06). CONCLUSION: The results do not support a major role for asporin D repeat polymorphism in the susceptibility to rheumatoid arthritis. Nevertheless, they support the influence of this gene on the outcome of the disease.

Anti-centromere antibodies in patients with systemic lupus erythematosus.

BACKGROUND: Anti-centromere autoantibodies (ACA) are frequently detected in systemic sclerosis (SScl), especially in the calcinosis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly, telangiectasia (CREST) syndrome, in which a prevalence of 55% has been reported. The presence of ACA in systemic lupus erythematosus (SLE) is so rare that its detection can raise serious doubts about the validity of the diagnosis. OBJECTIVE: To determine the frequency of ACA positive subjects from a wide monocentric cohort of SLE patients and analyse the clinical and biological characteristics of this group. METHODS: Five hundred and sixty consecutive SLE patients were systematically analysed for the presence of ACA and other autoantibodies using indirect immunofluorescence, counter-immunoelectrophoresis, double immunodiffusion, enzyme-linked immunosorbent assay (ELISA), and Western-blot. RESULTS: ACA were detected in 11 SLE patients (1.9%); all of them were women. The CENP-B-specific ELISA was positive in all patients. The main clinical features of scleroderma (cutaneous sclerosis, sclerodactylia, digital ulcers, or pulmonary fibrosis) were not present in these patients, who did not differ clinically from the whole SLE group. CONCLUSIONS: ACA can be detected in patients with genuine SLE without concurrent scleroderma. Therefore, the presence of this antibody does not preclude the possibility of the diagnosis of SLE. In addition, SLE patients with ACA do not represent a different clinical subgroup.