Differential Expression of SMAD Genes and S1PR1 on Circulating CD4+ T Cells in Multiple Sclerosis and Crohn's Disease

The Th17 immune response plays a key role in autoimmune diseases such as multiple sclerosis (MS) and inflammatory bowel disease (IBD). Expression of Th17-related genes in inflamed tissues has been reported in autoimmune diseases. However, values are frequently obtained using invasive methods. We aimed to identify biomarkers of MS in an accessible sample, such as blood, by quantifying the relative expression of 91 Th17-related genes in CD4+ T lymphocytes from patients with MS during a relapse or during a remitting phase. We also compared our findings with those of healthy controls. After confirmation in a validation cohort, expression of SMAD7 and S1PR1 mRNAs was decreased in remitting disease (-2.3-fold and -1.3-fold, respectively) and relapsing disease (-2.2-fold and -1.3-fold, respectively). No differential expression was observed for other SMAD7-related genes, namely, SMAD2, SMAD3, and SMAD4. Under-regulation of SMAD7 and S1PR1 was also observed in another autoimmune disease, Crohn's disease (CD) (-4.6-fold, -1.6-fold, respectively), suggesting the presence of common markers for autoimmune diseases. In addition, expression of TNF, SMAD2, SMAD3, and SMAD4 were also decreased in CD (-2.2-fold, -1.4-fold, -1.6-fold, and -1.6-fold, respectively). Our study suggests that expression of SMAD7 and S1PR1 mRNA in blood samples are markers for MS and CD, and TNF, SMAD2, SMAD3, and SMAD4 for CD. These genes could prove useful as markers of autoimmune diseases, thus obviating the need for invasive methods.

[Validation of genetic polymorphisms associated to the toxicity of chemotherapy in colorectal cancer patients]

OBJECTIVE

To validate the associations previously found in three cohorts of patients from the General University Hospital Gregorio Marañón, between the polymorphisms rs1128503, rs2032582 and rs1045642 of the ABCB1 gene and the hand-foot syndrome and diarrhea in colorectal cancer patients treated with chemotherapy regimes containing Capecitabine and 5-Fluorouracil, respectively, and between the polymorphisms rs2297595 of the DPYD gene and nausea/vomiting, rs11615 of ERCC1 and neutropenia, and rs28399433 CYP2A6 and neutropenia, in colorectal cancer patients treated with FOLFOX or XELOX as adjuvant therapy.

METHOD

Colorectal cancer patients treated with chemotherapy regimes, containing Capecitabine (n = 157), 5-Fluorouracil (n = 99) were included in the study, as well as patients treated with XELOX or FOLFOX (n = 83) as adjuvant therapy. The patients included were recruited from the Doce de Octubre University Hospital and from the Gregorio Marañón General University Hospital, and signed the informed consent form. DNA was obtained from blood samples. Genotyping was carried out with SNaPshot. Contingency tables were created for analyzing the associations between the genotypes and the adverse reactions.

RESULTS

None of the associations previously identified was replicated in the validation cohort.

CONCLUSIONS

Pharmacogenetic studies with a limited sample size must be validated with bigger cohorts, if possible by means of multicentre studies, reducing the variables to the maximum and should never be used in clinical practice without validation.

Pharmacogenomics in colorectal cancer: a genome-wide association study to predict toxicity after 5-fluorouracil or FOLFOX administration

The development of genotyping technologies has allowed for wider screening for inherited causes of variable outcomes following drug administration. We have performed a genome-wide association study (GWAS) on 221 colorectal cancer (CRC) patients that had been treated with 5-fluorouracil (5-FU), either alone or in combination with oxaliplatin (FOLFOX). A validation set of 791 patients was also studied. Seven SNPs (rs16857540, rs2465403, rs10876844, rs10784749, rs17626122, rs7325568 and rs4243761) showed evidence of association (pooled P-values 0.020, 9.426E-03, 0.010, 0.017, 0.042, 2.302E-04, 2.803E-03) with adverse drug reactions (ADRs). This is the first study to explore the genetic basis of inter-individual variation in toxicity responses to the administration of 5-FU or FOLFOX in CRC patients on a genome-wide scale.

Activity of Ertapenem and Ceftriaxone in the eradication of Salmonella in a model of experimental peritonitis in mice

Since the beginning of the 1990s, the prevalence of isolates of non-typhoidal Salmonella species resistant to antimicrobial agents, including those commonly used for the treatment of Salmonella infections such as fluoroquinolones, trimethoprim-sulfamethoxazole or beta-lactams, has increased substantially. Infections caused by multidrug-resistant strains of non-typhoidal Salmonella are now frequently encountered. In order to consider an appropriate role of Ertapenem in Salmonella-due intraabdominal infections, in the present study we compare the efficacy of Ertapenem versus that of Ceftriaxone in a mouse peritonitis model. Bacteriological eradication from blood, liver and mesenteric lymph nodes was observed after 5 and 7 days of treatment in all infected mice receiving ceftriaxone. Although both antimicrobial agents -Ertapenem and Ceftriaxone- were observed to be effective in reducing mortality in inoculated mice, our data suggests a reduced efficacy of Ertapenem in the bacteriological eradication of Salmonella enterica serotype Typhimurium in a mouse peritonitis model.

Antibodies and PMBC from EIAV infected carrier horses recognize gp45 and p26 synthetic peptides

Equine infectious anemia virus (EIAV) is a lentivirus causing a persistent infection in horses characterized by recurrent febrile episodes and high levels of viremia associated with a novel antigenic strain of the virus. The virus contains two envelope glycoproteins, gp90 and gp45, and four internal proteins, p26, p15, p11 and p9. Considering that the most infected horses are able to restrict EIAV replication to very low levels and that gp45 and p26 contain highly conserved epitopes among lentiviruses, it would be necessary to identify those conserved epitopes stimulating cellular and humoral responses. The aims of this study were to determine if the synthetic peptides identified as gp45 (aa 523-547) and p26 (aa 318-346) representing two highly conserved and immunodominant regions of EIA virus are recognized by PBMC and antibodies to EIAV adult mixed-breed naturally infected carrier horses, and if these peptides are able to induce immune responses in mice. Antibodies from 100% of carrier horses, evaluated by ELISA, recognized both peptides; PBMC from 80% of carrier horses, evaluated by lymphoproliferation assay, recognized, at least, one peptide. Furthermore, immunization with 100 microg of each peptide elicited humoral and cellular responses in BALB/c mice, antibodies appeared at 48 or 63 days of immunization with gp45 or p26, respectively. Although the kinetics of gp45- and p26-specific antibody responses were similar, percentage of positivity was higher for gp45. The lymphoproliferation assay, evaluated by BrdU uptake, was higher in mice immunized with gp45 or p26 than in the control group (P<0.05). Based on our findings, we consider that both peptides could be included in an effective vaccine design to induce long-term immunological memory.

Participation of RANTES and T-Cell Apoptosis in Human Renal Allograft

The aim of this study was to evaluate the serum RANTES (Regulated upon Activation of Normal T cell Expressed and Secreted) levels and the expression of CCR5, as well as the percentage of apoptotic cells, in peripheral T lymphocytes from renal transplanted patients with acute rejection (AR), chronic rejection (CR) or stable evolution (SE). RANTES serum levels were determined by enzyme-linked immunoadsorbent assay and CCR5 expression, as well as the percentage of apoptotic lymphocytes, on a FACScan flow cytometer. After staining with different antibodies, the cells were subjected to three-colour flow cytometric analysis. Data analysis was performed using winmdi 2.5 software. The serum RANTES level and percentages of CCR5/CD4 and CCR5/CD8 T lymphocytes in CR, AR and SE were lower than that in the control group (P <0.05). The level of CD4 and CD8 T lymphocytes in early apoptosis was higher in AR patients than in CR, SE or C groups (P <0.05). In the case of late apoptosis, the percentage of apoptotic/necrotic cells was higher in the CR than AR, SE or C groups (P <0.05). The RANTES serum levels and the percentage of peripheral CCR5 T lymphocytes would not indicate the renal allograft state. The increase of early apoptotic T lymphocytes could be a marker of AR process and could also indicate the initial step in reducing the cytotoxic T lymphocytes, thus favouring the graft evolution.

CXCR3 chemokine receptor distribution in normal and inflamed tissues: expression on activated lymphocytes, endothelial cells, and dendritic cells

Using new human CXCR3 chemokine receptor-specific monoclonal antibodies, we studied human CXCR3 tissue distribution in lymphoid and nonlymphoid organs, as well as in inflammatory conditions, including rheumatoid arthritis, Hashimoto's thyroiditis, and dermal vasculitis. CXCR3 was expressed by certain dendritic cell subsets, specifically myeloid-derived CD11c positive cells, not only in those present in normal lymphoid organs, but also in germinal centers generated in inflammatory conditions. CXCR3 expression was also detected in some lymphocyte subsets such as intraepithelial lymphocytes of secondary lymphoid organs and infiltrating lymphocytes in inflammatory conditions. In addition, CXCR3 was constitutively expressed by endothelial cells (EC) of vessels of medium and large caliber but not in small vessels from different organs. Finally, enhanced CXCR3 expression was found in EC and in infiltrating lymphocytes with an activated phenotype in inflammatory diseases. The CXCR3 chemokine receptor may play a role in the regulation of leukocyte migration to inflammatory sites.

The cell cycle inhibitor p21 controls T-cell proliferation and sex-linked lupus development

Here we show that the cell-cycle regulator p21 is involved in immune system function. T lymphocytes from p21-/- mice exhibit significant proliferative advantage over wild-type cells following prolonged stimulation, but not after primary activation. Consistent with this, p21-deficient mice accumulate abnormal amounts of CD4+ memory cells, and develop loss of tolerance towards nuclear antigens. Similar to human lupus, female p21-deficient mice develop antibodies against dsDNA, lymphadenopathy, and glomerulonephritis, leading to decreased viability. These data demonstrate a specialized role for p21 in the control of T-cell proliferation, tolerance to nuclear antigens, and female-prone lupus. These findings could be the basis for new therapeutic approaches to lupus.

Activity of trimethoprim/sulfamethoxazole plus polymyxin B against multiresistant Stenotrophomonas maltophilia

The inhibitory activity of eight antibiotics and the inhibitory and bactericidal activities of combinations of trimethoprim/sulfamethoxazole (TMP/SMX) plus three fixed concentrations of polymyxin B (0.01 microgram/ml, 0.1 microgram/ml and 0.5 microgram/ml) against 30 multi-resistant strains of Stenotrophomonas maltophilia were tested. Polymyxin B at 0.01 microgram/ml modified the inhibitory activity of TMP/SMX against only 40% of strains. At 0.1 microgram/ml and 0.5 microgram/ml, polymyxin B enhanced the inhibitory activity of TMP/SMX activity against all strains. Polymyxin B enhanced the bactericidal activity of TMP/SMX only at concentrations near the minimum inhibitory concentration of polymyxin B alone.

Multicenter Spanish study of ciprofloxacin susceptibility in gram-negative bacteria. The Spanish Study Group on Quinolone Resistance

The susceptibility of 2,426 gram-negative bacteria obtained from 18 Spanish hospitals to ciprofloxacin was evaluated. Among different medical centers, susceptibility to ciprofloxacin ranged from 83 to 100% for Enterobacteriaceae, from 35 to 100% for Pseudomonas aeruginosa, from 0 to 100% for Xanthomonas maltophilia, Acinetobacter spp. and other gram-negative non-fermenting bacilli, and from 33 to 100% for Campylobacter spp. All clinical isolates of Haemophilus influenzae, Moraxella catarrhalis and Neisseria gonorrhoeae were susceptible to ciprofloxacin.

Nonspecific immunity in Down syndrome: a study of chemotaxis, phagocytosis, oxidative metabolism, and cell surface marker expression of polymorphonuclear cells

We have investigated several aspects of nonspecific immunity in Down syndrome (DS), utilizing peripheral polymorphonuclear leukocytes (PMNL), obtained from 12 children aged 8-16, diagnosed as trisomy 21, and their healthy matched controls. We used the under agarose method for chemotaxis assays, and flow cytometry for the determination of phagocytosis of monodispersed fluorescent beads, metabolic burst activity, and neutrophil surface marker expression on these cells. Our results indicate that a chemotactic defect exists in PMNL of DS children. However, no statistically significant differences were found between PMNL from DS children and those from controls in phagocytosis, oxidative burst, and expression of the markers CD11a, CD11b, CD16, and CD 18. Furthermore, no overexpression of CD11a and CD18 was present as a consequence of gene overdosage in PMNL from DS children. On the other hand, 3 different neutrophil subpopulations could be observed according to the CD16 staining pattern in DS children and controls; this might be a consequence of genetic variation or may represent different states of activation of these cells. Other factors such as T-cell involvement, and the role of cytokines, cyclic nucleotides, and zinc serum levels in DS patients should be further investigated in order to define the causes of the immunological derangement present in this condition.

[Endoscopic sclerotherapy of esophageal varices in pediatric patients]

Endoscopic sclerotherapy was performed for esophageal variceal sclerosis in 7 children, aged 18 months to 11 years. Five of them had cavernomatous portal degeneration and the other two hepatic cirrhosis. The technique used was intra- and perivariceal with ethanolamine oleate in order to get the decrease or disappearance of the variceal veins. Two of the patients showed retrosternal pain and fever after the sclerosis procedure. This preliminary report shows that endoscopic sclerosis of esophageal varices is a good procedure to control acute bleeding and to prevent its onset in children.