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J Alcocer-Varela

Publications and source records attributed to J Alcocer-Varela.

At least 19 recordsLinked to original sources
PubMed2005

IL-15 and IL-15R in leucocytes from patients with systemic lupus erythematosus.

OBJECTIVE: To assess the functional status of the IL-15/IL-15Ralpha cytokine system in different leucocyte subsets from patients with systemic lupus erythematosus (SLE). METHODS: Eighteen patients with SLE (10 with inactive and eight with active disease) and 14 healthy individuals were studied. Serum levels and in vitro production of IL-15 were determined. In addition, the expression of IL-15 receptor alpha (IL-15Ralpha) and membrane-bound IL-15 was assessed and the in vitro effects of IL-15 on CD69 and CD64 expression, interferon-gamma and TNF-alpha synthesis, respiratory burst induction and apoptosis were studied. RESULTS: Serum levels of IL-15 were significantly increased in inactive and active patients with SLE. Accordingly, the in vitro synthesis and release of IL-15 by monocytes in response to IFN-gamma+lipopolysaccharide was significantly enhanced in SLE patients with active disease, as was the percentage of membrane-bound IL-15+ monocytes. On the other hand, enhanced basal expression of IL-15Ralpha was detected in leucocytes from SLE patients, with defective induction upon stimulation with phytohaemagglutinin or phorbol myristate acetate/ionomycin. Furthermore, diminished induction of CD69 expression and interferon-gamma and TNF-alpha synthesis by recombinant human IL-15 was detected in peripheral blood mononuclear cells from SLE, and there was defective induction of CD64 and priming for respiratory burst in neutrophils. The anti-apoptotic effect of IL-15 was diminished in leucocytes from SLE patients. CONCLUSION: Our data indicate that there is enhanced synthesis of IL-15 by immune cells from SLE patients, with a poor response to this cytokine by different leucocyte subsets. This abnormal function of IL-15/IL-15Ralpha may contribute significantly to the pathogenesis of SLE.

Adolescent↗
PubMed2004

Is damage in central nervous system due to inflammation?

The aim of this work was to review the inflammatory factors involved in central nervous system (CNS) inflammation and the damage associated to their participation in an inflammatory disease of CNS, multiple sclerosis in humans and experimental allergic encephalomyelitis in the murine model. Inflammation has an important repairing function, nevertheless frequently in the CNS inflammation is the cause of damage and it does not fulfill this repairing function as it happens in other compartments of the body. The inflammatory response in the CNS involves the participation of different cellular types of the immune system (macrophages, mast cells, T and B lymphocytes, dendritic cells) and resident cells of the CNS (microglia, astrocytes, neurons), adhesion molecules, cytokines and chemokines among other proteic components. During neuroinflammation chemotaxis is an important event in the recruitment of cells to the CNS. The lymphocyte recruitment implies the presence of chemokines and chemokine receptors, the expression of adhesion molecules, the interaction between lymphocytes and the bloodbrain barrier (BBB) endothelium, and finally their passage through the BBB to arrive at the site of inflammation. If this process is not controlled, is prolonged, inflammation loses its repairing function and can be the cause of damage. Usually neuroinflammation has the tendency to decline to damage, which would explain most of the CNS pathologies.

Animals↗
PubMed2004

Neuroendocrine dopaminergic regulation of prolactin release in systemic lupus erythematosus: a possible role of lymphocyte-derived prolactin.

Prolactin (PRL) secretion by the pituitary is under the control of dopamine. Hyperprolactinemia has been found in patients with systemic lupus erythematosus (SLE) and seems to be associated with clinical activity. T-lymphocytes express PRL and those from SLE patients appear to secrete more PRL than controls. In this study, immuno-(RIA) and bio-(BIO) assayable PRL in both serum and culture media of peripheral blood mononuclear cells (PBMNC) from SLE and control subjects were evaluated in the basal state and in response to 10 mg oral administration of metoclopramide, a dopamine receptor antagonist. Prolactin size heterogeneity in serum and culture media and PRL gene transcription in PBMNC were also studied. Basal serum RIA-PRL, BIO-PRL and the BIO/RIA ratio were similar in both groups. The serum BIO-PRL response after metoclopramide was higher than RIA-PRL in SLE, and this increment was also greater than in control subjects. PBMNC from SLE subjects secreted and produced more BIO-PRL. After metoclopramide, secretion and production of PRL increased only in PBMNC from control women and not in those from SLE patients. Our results demonstrated an increased central dopaminergic tone in SLE and suggest that lymphocyte-derived PRL might contribute to alter the functional activity of the hypothalamic dopaminergic system in SLE attempting to maintain serum PRL within a physiological range.

Adult↗
PubMed2004

Antinucleosome antibodies may help predict development of systemic lupus erythematosus in patients with primary antiphospholipid syndrome.

Patients with primary antiphospholipid syndrome (PAPS) may evolve to systemic lupus erythematosus (SLE), even many years later. This makes differentiation between primary and secondary antiphospholipid syndrome a difficult task. Studies in murine models of lupus have shown that the development of antinucleosome (anti-NCS) antibodies may occur from the early stages of life. We therefore hypothesize that anti-NCS antibodies could help predict development of SLE in patients with PAPS. We studied anti-NCS antibodies in 18 PAPS patients (15 female, three male), followed for a mean of 11 years to evaluate the potential development of SLE. When PAPS was diagnosed, nine patients were positive for anti-NCS antibodies. Six of them developed clinical manifestations of SLE. In contrast, none of the patients who were negative to anti-NCS antibodies developed it. These findings suggest that anti-NCS antibodies could help predict which patients with PAPS may eventually develop SLE.

Adolescent↗
PubMed2003

Anti-nucleosome antibodies in patients with systemic lupus erythematosus of recent onset. Potential utility as a diagnostic tool and disease activity marker.

OBJECTIVE: To compare the utility of anti-chromatin antibodies for the diagnosis of systemic lupus erythematosus (SLE) and as markers of disease activity. METHODS: We included 73 consecutive patients (62 female) with SLE (four or more ACR criteria) of recent onset (<1 yr since diagnosis). As control groups we included 130 healthy blood donors and 261 patients with 11 systemic autoimmune diseases (SAD). Disease activity was assessed using the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). A venous blood sample was drawn to measure three anti-chromatin antibodies [anti-nucleosome (anti-NCS), anti-double-stranded DNA (anti-dsDNA) and anti-histones (anti-HST)] by enzyme-linked immunosorbent assay. RESULTS: The prevalence of anti-chromatin antibodies in SLE patients and healthy controls was 100 and 3% respectively for anti-NCS, 63 and 5% for anti-dsDNA, and 15 and 3% for anti-HST. Anti-NCS had a sensitivity of 100% and specificity of 97% for SLE diagnosis. When SLE and SAD patients were compared [excluding mixed connective tissue disease (MCTD)], the sensitivity of anti-NCS, anti-dsDNA and anti-HST antibodies for SLE diagnosis was 93, 71 and 40% respectively and the specificity was 97, 98 and 98%. Anti-chromatin antibodies were not useful in differentiating between SLE and MCTD patients. Anti-NCS antibodies showed the highest correlation with disease activity (r = 0.45, P < 0.0001), especially in patients negative for anti-dsDNA antibodies (r = 0.58, P = 0.001). Anti-NCS antibodies also showed strong association with renal damage (odds ratio 4.1, 95% confidence interval 1.2-13.6, P = 0.01). CONCLUSION: Anti-NCS antibodies could be a useful tool in the diagnosis and assessment of disease activity in SLE patients, especially in patients who are negative for anti-dsDNA antibodies.

Adolescent↗
PubMed2003

Prevalence of antineutrophil cytoplasmic autoantibodies in patients with tuberculosis.

OBJECTIVE: To determine the prevalence of antineutrophil cytoplasmic autoantibodies (ANCA) in sera of patients with tuberculosis compared with healthy control subjects and a group of patients with atopic asthma. METHODS: The presence of ANCA was examined in patients with tuberculosis, and in asthmatic patients and healthy subjects as control groups, by means of indirect immunofluorescence (IIF) and enzyme-linked immunosorbent assay (ELISA) to detect anti-proteinase 3 (PR3-ANCA) and antimyeloperoxidase (MPO-ANCA) antibodies. RESULTS: ANCA were present in 20 (44.4%) of 45 tuberculosis patients by IIF (16 c-ANCA, four p-ANCA) and in 18 (40%) patients by ELISA (15 PR3-ANCA, three MPO-ANCA). High odds ratios for ANCA positivity were observed for tuberculosis patients when compared with both control groups. ANCA results were not related to the category of tuberculosis, stage of disease, presence of concomitant diseases or pharmacotherapy. CONCLUSIONS: As many clinical similarities between tuberculosis and Wegener's granulomatosis exist, we propose that a positive ANCA test in patients living in countries with a high prevalence of tuberculosis must be carefully interpreted as indicative of systemic vasculitis, especially when no signs of extrapulmonary involvement occur.

Adult↗
PubMed2003

Immunoregulatory defects in patients with systemic lupus erythematosus in clinical remission.

Little is known about the immune system of patients with systemic lupus erythematosus (SLE) during periods of silent disease. To address this issue we analysed lymphoid populations andcytokine production of mononuclear cells obtained from SLE patients in remission. We studied 43 patients with inactive disease, 10 with active disease and 30 controls. Remission was defined as at least 1 year during which lack of clinical disease activity permitted withdrawal of all treatment. Remission length ranged from 1 to 30 years. Flow cytometry and ELISA were used to study lymphoid populations (CD4, CD8 and CD19) and cytokine production (IL-2, 4, 10, 12 and 18). Patients with short remission periods (up to 15 years) exhibited an increased percentage of B cells; production of IL-2, IL-10 and IL-12 was decreased; production of IL-18 was increased. Interestingly, patients from groups with long time of inactive disease had corrected most alterations, but had an impaired IL-18 expression. IL-12 production correlated strongly with the length of the remission period (r = 0.7565). The immune system of patients with inactive lupus has partially corrected the disturbances present during disease activity. This is accomplished gradually, sometimes until counter-regulatory alterations are developed. This may allow patients to remain without disease activity.

Adolescent↗
PubMed2002

Mediators of inflammation are down-regulated while apoptosis is up-regulated in rheumatoid arthritis synovial tissue by polymerized collagen.

The aim of the study was to determine whether collagen-polyvinylpyrrolidone (collagen-PVP) modifies some proinflammatory responses in synovium cultures from rheumatoid arthritis (RA) patients. Synovium from 10 RA patients were cultured with or without 1% collagen-PVP. Tissues on the 3rd, 5th and 7th culture day were sectioned and stained by the Herovici technique. Total collagen and type I/III collagen ratios were evaluated by the Woessner micromethod and by interrupted gel electrophoresis, respectively. Collagenolytic activity was assessed by degradation of [3H]-collagen in supernatants. TIMP-1, IL-1beta and TNF-alpha were determined in supernatants by ELISA, and the results were normalized by DNA concentration. IL-1beta, TNF-alpha, IL-6, IL-8, MMP-1, TIMP-1, Cox-1, VCAM-1, ICAM-1 and Fas/APO95 expression was evaluated by immunohistochemistry. Apoptosis was detected by TUNEL technique. The histological analysis and electrophoresis revealed a 1.7-fold increase of type III collagen in a time-dependent fashion in collagen-PVP-treated cultures. Proinflammatory cytokines (IL-1beta: 58 +/- 9 versus 22 +/- 10; TNF-alpha: 41 +/- 6 versus 11 +/- 3; IL-8: 59 +/- 12 versus 29 +/- 9; treated versus untreated), adhesion molecule (ICAM-1: 57 +/- 11 versus 29 +/- 15; VCAM-1: 49 +/- 7 versus 21 +/- 13; treated versus untreated) as well as Cox-1 (59 +/- 10 versus 20 +/- 3) expression was down-regulated in RA synovium treated. Meanwhile, TIMP-1 (36 +/- 7 versus 57 +/- 11) and Fas expression (20 +/- 10 versus 55 +/- 13) and apoptosis (14 +/- 3 versus 55 +/- 5) were up-regulated in treated cultures compared with controls. In supernatants, the collagenolytic activity, as well as IL-1beta and TNF-alpha, levels were all down-regulated in treated cultures (two, three, fourfold, respectively). The addition of collagen-PVP to synovium-induced down-modulation of some inflammatory parameters and an increase in apoptosis of synovial cells. Perhaps this mechanism could contribute to inhibit outgrowth of pannus formation and to down-regulate inflammation of joints in patients with RA.

Adult↗
PubMed2002

Purified protein derivative reaction in systemic lupus erythematosus patients. Indirect study of cellular immunity.

Cutaneous anergy in SLE patients results from disease activity and/or immunosuppressive treatment (IT). The aim of this study was to evaluate purified protein derivative (PPD) reaction in SLE patients. A total of 145 patients and 20 controls were studied. Five units of PPD were applied on day 0, and skin reaction was measured after 3 (PPD1) and 6 (PPD2) days. A booster was applied (day 14), and the reaction was measured after 3 (PPD3) and 6 (PPD4) days. Non-parametric ANOVA test and unpaired Student's t-test were performed. Forty patients (group I) were inactive (MexSLEDAI < 3), receiving no IT (at least 3 months previous to the PPD test); 39 (group II) were inactive receiving IT; 24 (group III) were active without IT, and 42 (group IV) were active with IT. Active patients had lower PPD1 (group III, 1.4 +/- 0.9; group IV, 0.6 +/- 0.5) than inactive patients (group I, 8.4 +/- 2.3; group II, 5.1 +/- 1.9) and than controls (9.4 +/- 3; P < or = 0.001). Group IV had lower delayed response (PPD2 = 0.3 +/- 0.3) than inactive groups (group I, 2.6 +/- 0.9; group II, 3.1 +/- 0.8) and than controls (7.9 +/- 2.5; P < or = 0.001). Group III had lower delayed reaction (PPD2 = 1.2 +/- 0.8) than controls (P < or = 0.001). Active SLE patients, receiving or not receiving IT, had lower skin response to PPD than inactive patients and controls.

Adult↗
PubMed2001

Class II allele and haplotype frequencies in Mexican systemic lupus erythematosus patients: the relevance of considering homologous chromosomes in determining susceptibility.

The aim of the present study was to determine the relevant major histocompatibility complex (MHC) class II alleles in the genetic susceptibility to systemic lupus erythematosus (SLE) in Mexican Mestizo patients. We examined the gene and haplotype frequencies of the HLA-DRB1, DQA1 and DQB1 alleles by polymerase chain reaction-sequence-specific oligonucleotide probes in 81 Mexican SLE Mestizo patients and 99 ethnically matched controls. We found a significantly increased frequency of the HLA-DRB1*0301 (p(c) = 0.031, odds ratio = 2.63) allele and significantly decreased frequencies of the DRB1*0802 (p(c) = 0.035) and DRB1*1101 (p(c) = 0.037) alleles in the SLE group. Haplotype analysis showed increased frequencies of DRB1*0301-DQA1*0501-DQB1*0201 (p(c) = 0.017, odds ratio = 2.97), and decreased frequency of DRB1*0802-DQA1*0401-DQB1*0402 (p(c) = 0.034) in SLE patients. The most frequently detected haplotypes in SLE patients showed different haplotypic combinations in the homologous chromosome from those found in controls. Thus, the combinations detected in SLE patients were either not detected in the control group or infrequently found. The results suggest that the DRB1*0301 is the principal class II allele associated with the genetic susceptibility to SLE in Mexican patients and that the presence of a specific haplotype of the homologous chromosome in patients with DRB1*0407-DQA1*03-DQB1*0302 and DRB1*1501-DQA1*0102-DQB1*0602 haplotypes could have an additive effect on the susceptibility to the disease. Finally, the low frequency of the DRB1*0301 and DRB1*1501 alleles in the control population suggests that the genetic admixture between Mexican Indians and Caucasian populations was an event that could have increased the risk of Mexicans to develop SLE.

Alleles↗
PubMed2000

Fine mapping of the SLEB2 locus involved in susceptibility to systemic lupus erythematosus.

We have previously reported linkage of systemic lupus erythematosus to chromosome 2q37 in multicase families from Iceland and Sweden. This locus (SLEB2) was identified by linkage to the markers D2S125 and D2S140. In the present study we have analyzed additional microsatellite markers and SNPs covering a region of 30 cM around D2S125 in an extended set of Nordic families (Icelandic, Swedish, and Norwegian). Two-point linkage analysis in these families gave a maximum lod score at the position of markers D2S2585 and D2S2985 (Z = 4.51, PIC = 0.65), by applying a "model-free" pseudo-marker linkage analysis. Based on multipoint linkage analysis in the Nordic families, the most likely location of the SLEB2 locus is estimated to be in the interval between D2S125 and the position of markers D2S2585 and D2S2985, with a peak multipoint lod score of Z = 6.03, assuming a dominant pseudo-marker model. Linkage disequilibrium (LD) analysis was performed using the data from the multicase families and 89 single-case families of Swedish origin, using the same set of markers. The LD analysis showed evidence for association in the single-case and multicase families with locus GAAT3C11 (P < 0.0003), and weak evidence for association was obtained for several markers located telomeric to D2S125 in the multicase families. Thirteen Mexican families were analyzed separately and found not to have linkage to this region. Our results support the presence of the SLEB2 locus at 2q37.

Base Sequence↗
PubMed2000

Clinical and biologic effects of anti-interleukin-10 monoclonal antibody administration in systemic lupus erythematosus.

OBJECTIVE: To evaluate the safety and clinical efficacy of administering an anti-interleukin-10 (anti-IL-10) monoclonal antibody (mAb) to systemic lupus erythematosus (SLE) patients with active and steroid-dependent disease. In addition, we sought to assess the effects of in vivo IL-10 neutralization on biologic markers of SLE. METHODS: Treatment consisted of 20 mg/day intravenous administration of an anti-IL-10 murine mAb (B-N10) for 21 consecutive days, with a followup period of 6 months. Six patients were studied. RESULTS: Treatment was safe and well tolerated. All patients developed antibodies against B-N10. Cutaneous lesions and joint symptoms improved in all patients beginning during B-N10 administration and continuing to month 6. The SLE Disease Activity Index decreased from a mean +/- SEM of 8.83+/-0.91 on day 1 to 3.67+/-0.67 on day 21 (P = 0.001), 1.50+/-0.84 at month 2, and 1.33+/-0.80 at month 6 (P<0.001). At the end of followup, the disease was clinically inactive in 5 of the 6 patients. Prednisone administration was decreased from a mean +/- SEM of 27.9+/-5.7 mg/day on day 1 to 9.6+/-2.0 mg/day at month 6 (P<0.005). Activity of immune and endothelial cells rapidly decreased, as assessed by the early evolution of several biologic markers. CONCLUSION: This is the first report of IL-10 antagonist administration to humans. The study shows the involvement of IL-10 in the pathogenesis of SLE, and indicates that the use of IL-10 antagonists may be beneficial in the management of refractory SLE.

Adolescent↗
PubMed2000

Association analysis with microsatellite and SNP markers does not support the involvement of BCL-2 in systemic lupus erythematosus in Mexican and Swedish patients and their families.

We have described suggestive linkage between microsatellite markers within the cytogenetic region 18q21-23 and SLE, a region where linkage with other autoimmune diseases has also been detected. The Bcl-2 gene located within this region, is a candidate gene because of its role in apoptosis, a physiological mechanism that could be deregulated in autoimmune disease. Furthermore, several studies have found abnormalities of Bcl-2 expression in SLE patients. We therefore sought to determine if the Bcl-2 gene is involved in SLE by studying members of a large cohort of Mexican SLE patients (n = 378) and 112 Swedish simplex families. Using a microsatellite marker and two single nucleotide polymorphisms located within the gene, we were unable to detect association between Bcl-2 and SLE in either population. We also tested whether combinations of alleles of the Bcl-2 and IL-10.G microsatellites would increase the risk for SLE. Our results do not support such hypothesis. Our findings suggest that linkage between SLE and the 18q21-23 region is due to a gene other than Bcl-2.

Alleles↗
PubMed2000

Lack of association between the polymorphism at the heat-shock protein (HSP70-2) gene and systemic lupus erythematosus (SLE) in the Mexican mestizo population.

Major histocompatibility complex (MHC) alleles have been recognized as genetic factors for developing systemic lupus erythematosus (SLE). In the present study we analyzed whether a heat-shock protein gene (HSP70-2) is involved in determining susceptibility to develop SLE in a Mexican Mestizo population. A HSP70-2 Pst I polymorphism was detected by a restriction fragment length polymorphism analysis of polymerase chain reaction (PCR-RFLP) in 107 SLE patients and 158 healthy controls. No statistically significant differences were observed in the HSP70-2 allele distribution between patients and healthy controls. HLA-DR analysis showed an increased frequency of HLA-DR3 allele in the patients group (P < 0.05, OR = 2.26, EF = 6.0%). On the other hand, when we analyzed HSP70-2 polymorphism in relation to HLA-DR3 allele, we could only detect an increased frequency of AB genotype in the DR3 negative patients (pC < 0.05, RR = 2.6, EF = 11.3%). Linkage disequilibrium was observed for three haplotypes: HLA-DR3-HSP70-2A (D = 0.03, D' = 0.67, P < 0.01); HLA-DR1-HSP70-2A (D = 0.03, D' = 0.86, P < 0.01) and HLA-DR8-HSP70-2B (D = 0.02, D' = 0.46, P = 0.02). Our data indicate that HSP70-2 gene polymorphism as opposed to the other ethnic groups does not appear to be relevant in SLE susceptibility in Mexican patients and that the distribution of the different alleles depend on the frequency of HLA alleles associated with them.

Alleles↗
PubMed1999

A comparison of genome-scans performed in multicase families with systemic lupus erythematosus from different population groups.

Systemic lupus erythematosus is a disease of unknown etiology. Multiple genetic factors are believed to be involved in its pathogenesis. In addition, and due to genetic heterogeneity, these factors and/or their combinations may be different in different ethnic groups, while some might be shared between populations. We have performed genome scans in multicase families from three different population groups, two from Northern Europe, with a high degree of homogeneity, and the third from a recently admixed population of Mexican Mestizos. Although our family material is relatively small, the results presented here show that using family sets from well defined populations are sufficient to detect susceptibility loci for SLE. Our results also reveal the chromosomal regions most likely to contain susceptibility genes for SLE.

Ethnicity↗
PubMed1999

Interleukin-8, interleukin-10, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 expression levels are higher in synovial tissue from patients with rheumatoid arthritis than in osteoarthritis.

The aim of this work was to determine differences in pro- and anti-inflammatory cytokine and adhesion molecule expression in synovial tissue from patients with rheumatoid arthritis (RA) or osteoarthritis (OA). Synovial tissue samples were obtained from patients with RA and OA, and from healthy individuals. The expression of mRNA of interleukin (IL)-1beta, IL-4, IL-6, IL-8, IL-10, IL-13, tumour necrosis factor-alpha (TNF-alpha) and transforming growth-factor-beta1 (TGF-beta1) was evaluated by the polymerase chain reaction (PCR). In addition, IL-8 and IL-10 transcripts were measured by quantitative PCR. The expression of IL-8 and IL-10 proteins was determined by immunoperoxidase staining. To evaluate the inflammatory stage of synovial tissue, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) protein expression was also determined. RA patients were found to display higher levels of adhesion molecules than patients with OA. PCR analysis showed a similar profile of cytokine transcripts between the OA and RA groups. Gene expression of IL-4 and IL-13 in synovium was undetectable. In contrast, IL-1beta, IL-6, IL-8, IL-10, TNF-alpha and TGF-beta1 transcripts were expressed by both groups. Increased levels of IL-8 and IL-10 transcripts and their proteins were observed in synovium from RA patients when compared to patients with OA and healthy controls. Thus, our data show that IL-8, IL-10, ICAM-1 and VCAM-1 expression levels are higher in synovial tissue from patients with RA than in similar tissue from patients with OA.

Adult↗