Isabela Jubé Wastowski

HLA-G Expression in the Skin of Patients with Systemic Sclerosis

Objective. To determine HLA-G expression in skin biopsies from patients with systemic sclerosis (SSc), and its association with epidemiological, clinical, and laboratory variables and survival. Methods. Paraffin-embedded skin biopsies obtained from 21 SSc patients (14 limited SSc, 7 diffuse SSc) and from 28 healthy controls were studied. HLA-G expression was evaluated by immunohistochemistry. Results. HLA-G molecules were detected in 57% of skin biopsies from patients with SSc (9 from limited SSc, 3 from diffuse SSc), whereas no control sample expressed HLA-G (p = 0.000004). In patients, HLA-G molecules were consistently observed within epidermal and some dermal cells. HLA-G expression was associated with a lower frequency of vascular cutaneous ulcers (p = 0.0004), telangiectasias (p = 0.008), and inflammatory polyarthralgia (p = 0.02). After a 15-year followup, SSc patients who exhibited HLA-G survived longer than patients who did not. Conclusion. HLA-G is expressed in skin biopsies from patients with SSc, and this is associated with a better disease prognosis. This suggests a modulatory role of HLA-G in SSc, as observed in other skin disorders.

HLA polymorphisms as incidence factor in the progression to end-stage renal disease in Brazilian patients awaiting kidney transplant.

Chronic renal failure (CRF) leads in the majority of instances to end-stage renal disease (ESRD) requiring renal replacement therapy. Age, gender, genetics, race, hypertension, and smoking among others are factors associated with ESRD. Our interest was to evaluate the possible associations of class I and II HLA antigens with ESRD renal disease independent of other factors, among patients with CRF, having various diagnoses in the Brazilian population of the São Paulo state. So 21 HLA-A, 31 HLA-B, and 13 HLA-DR were detected in 105 patients who were compared with 160 healthy controls of both sexes who were not related to the patients evaluated until 2005. We calculated allelic frequencies, haplotypes frequencies, etiological fractions (EF), preventive fractions, and relative risks (RR). We compared demographic data of patients and controls. The antigens positively associated with ESRD were: HLA-A78 (RR = 30.31 and EF = 0.96) and HLA-DR11 (RR = 18.87 and EF = 0.65). The antigens HLAB14 (RR = 29.90 and EF = 0.75) was present at a significantly lower frequency among patients compared with controls. In contrast, no haplotype frequency showed statically significant associations. Further molecular studies may clarify types and subtypes of alleles involved with ESRD progression.

Analysis of HLA-G gene polymorphism and protein expression in invasive breast ductal carcinoma.

The human leukocyte antigen G (HLA-G) is a non-classical HLA class I molecule predominantly expressed in trophoblastic placental cells to protect the fetus during pregnancy. However, evidence has shown that this molecule may be implicated in the immune escape mechanism of tumor cells. Thus, the aim of this study was to evaluate the frequency of 14-bp insertion/deletion HLA-G polymorphism, as well as the expression of this molecule in patients with invasive breast ductal carcinoma (IDC). A significant association between the expression of HLA-G and the presence of metastasis in lymph nodes (p=0.01) was observed and the expression of HLA-G was significantly higher in patients with shorter survival time (p=0.03). The analysis suggests that the polymorphism observed in patients with IDC may be inducing a higher expression of the HLA-G molecule, which may possibly contribute to shorter survival time and a worse clinical prognosis for such patients.

Association between the HLA-G molecule and lymph node metastasis in papillary thyroid cancer

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer and can present as lymph node metastasis in 30 to 65% of cases when initially diagnosed. High frequency recurrence, distant metastasis and treatment resistance can be found in cases of PTC so early diagnosis and treatment are critical for improved prognosis and better survival rates. The characterization of new biomarkers has proved useful for the diagnosis and follow-up of these patients. HLA-G is a non-classical HLA class I molecule whose expression in cancer cells has been associated with tumor evasion of immune response. Therefore, the aim of this study was to investigate the HLA-G expression and its clinical significance in PTC. Paraffin-embedded thyroid biopsies of 70 PTC patients (40 of whom had presented with metastasis) were evaluated. HLA-G-staining was observed in tumor cells in PTC, and the HLA-G expression was significantly associated with an increased occurrence of lymph node metastasis (p=0.0006) and capsular invasion (p=0.02). This preliminary data shows the HLA-G expression in thyroid carcinoma specimens for the first time and suggests that this expression could impair efficient anti-tumor immunity in PTC. This would indicate that HLA-G could have an independent prognostic value in PTC, principally for tumor recurrence.

Gene Expression Profiles Stratified according to Type 1 Diabetes Mellitus Susceptibility Regions

The MHC region (6p21) aggregates the major genes that contribute to susceptibility to type 1 diabetes (T1D). Three additional relevant susceptibility regions mapped on chromosomes 1p13 (PTPN22), 2q33 (CTLA‐4), and 11p15 (insulin) have also been described by linkage studies. To evaluate the contribution of these susceptibility regions and the chromosomes that house these regions, we performed a large‐scale differential gene expression on lymphomononuclear cells of recently diagnosed T1D patients, pinpointing relevant modulated genes clustered in these regions and their respective chromosomes. A total of 4608 cDNAs from the IMAGE library were spotted onto glass slides using robotic technology. Statistical analysis was carried out using the SAM program, and data regarding gene location and biological function were obtained at the SOURCE, NCBI, and FATIGO programs. Three induced genes were observed spanning around the MHC region (6p21–6p23), and seven modulated genes (5 repressed and 2 repressed) were seen spanning around the 6q21–24 region. Additional modulated genes were observed in and around the 1p13, 2q33, and 11p15 regions. Overall, modulated genes in these regions were primarily associated with cellular metabolism, transcription factors and signaling transduction. The differential gene expression characterization may identify new genes potentially involved with diabetes pathogenesis.

Predicting outcomes of balloon laryngoplasty in children with subglottic stenosis

UNLABELLED The treatment of subglottic stenosis in children remains a challenge for the otolaryngologist and may involve procedures such as endoscopy, open surgery, and often both. In the recent past, high-pressure balloons have been used in endoscopic treatment due to their relative facility and high success rates. OBJECTIVE To report success rates in the treatment of acquired subglottic stenosis with balloon laryngoplasty in children and identify predictive factors for the success of the technique and its complications. METHODS Descriptive, prospective study of children who were diagnosed with acquired subglottic stenosis and underwent balloon laryngoplasty as the primary treatment. RESULTS Balloon laryngoplasty was performed in 48 children with an average age of 20.7 months: 31 presented with chronic subglottic stenosis and 17 with acute stenosis. Success rate was 100% for acute and 39% for chronic subglottic stenosis. Success was significantly associated with several factors, including recently acquired stenosis, initial grade of stenosis, younger patient age, and the absence of tracheotomy. Complications were transitory dysphagia observed in three children and a submucosal cyst in one of the patients. CONCLUSIONS Balloon laryngoplasty may be considered as a first line of treatment for acquired subglottic stenosis. In acute cases, the success rate was 100%, and even though results are less promising in chronic cases, complications were not significant and the patients can undergo open surgery without contraindications. Predictive factors of success were acute stenosis, less severe grades of stenosis, younger patient age, and the absence of tracheotomy.

Relevance of HLA-G, HLA-E and IL-10 expression in lip carcinogenesis

HLA-G, HLA-E and IL-10 are molecules which can provide tumor immunosuppression as well as the capacity of evasion to the immune system host. This study set out to evaluate HLA-G, HLA-E and IL-10 expression in lip squamous cell carcinoma (LSCC) and in a potentially malignant disorder (actinic cheilitis - AC), correlating the expression of these proteins with the degree of epithelial dysplasia. Immunohistochemistry was undertaken to identify HLA-G, HLA-E and IL-10 in samples from patients with LSCC (n=20), AC (n=30) and healthy lip mucosa (control) (n=10). A semiquantitative scoring system was used for analysis. Differences between the groups were evaluated using the Pearson Chi-Squared test. The percentage of LSCC samples showing high immunoreactivity (IRS>2) for HLA-G, HLA-E and IL-10 (neoplastic/epithelial cells) and HLA-E (stroma/connective tissue) was significantly higher that of the control (P<0.05). A tendency for a progressive increase in the proteins analyzed was observed from the control to AC and to LSCC. The degree of dysplasia in the AC samples was not significantly associated with the proteins evaluated (P>0.05). The high expression of HLA-G, HLA-E and IL-10 in AC and LSCC reflects the capacity that these pathologies have for evasion and progression.

Patients with systemic sclerosis present increased DNA damage differentially associated with DNA repair gene polymorphisms.

Objective. Patients with systemic sclerosis (SSc) exhibit increased toxicity when exposed to genotoxic agents. In our study, we evaluated DNA damage and polymorphic sites in 2 DNA repair genes (XRCC1 Arg399Gln and XRCC4 Ile401Thr) in patients with SSc. Methods. A total of 177 patients were studied for DNA repair gene polymorphisms. Fifty-six of them were also evaluated for DNA damage in peripheral blood cells using the comet assay. Results. Compared to controls, the patients as a whole or stratified into major clinical variants (limited or diffuse skin involvement), irrespective of the underlying treatment schedule, exhibited increased DNA damage. XRCC1 (rs: 25487) and XRCC4 (rs: 28360135) allele and genotype frequencies observed in patients with SSc were not significantly different from those observed in controls; however, the XRCC1 Arg399Gln allele was associated with increased DNA damage only in healthy controls and the XRCC4 Ile401Thr allele was associated with increased DNA damage in both patients and controls. Further, the XRCC1 Arg399Gln allele was associated with the presence of antinuclear antibody and anticentromere antibody. No association was observed between these DNA repair gene polymorphic sites and clinical features of patients with SSc. Conclusion. These results corroborate the presence of genomic instability in SSc peripheral blood cells, as evaluated by increased DNA damage, and show that polymorphic sites of the XRCC1 and XRCC4 DNA repair genes may differentially influence DNA damage and the development of autoantibodies.

Association of Interferon-Gamma Gene Polymorphism (+874 T/A) with Systemic Sclerosis

Isabela J. Wastowskia,c,∗, Percival D. Sampaio-Barrosb,d, Gustavo Martelli-Palominoa, Joao Francisco Marques-Neto b, Janaina C.O. Crispim a, Diane M. Rassi a and Eduardo A. Donadi a Program of Basic and Applied Immunology, Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, Brazil Unit of Rheumatology, Department of Internal Medicine, Faculty of Medical Sciences, State University of Campinas, Campinas, Brazil Master’s Program in Genetics, Pontifical Catholic University of Goias, Goiânia, Brazil Division of Rheumatology, University of Sao Paulo, Sao Paulo, Brazil

Interleukin-17A expression in patients presenting with nasal polyposis

UNLABELLED Sinonasal polyposis (SNP) is a chronic inflammatory pathology of the nasal/paranasal cavities which affects from 1%-4% of the population. Although polyps seem to be a manifestation of chronic inflammation of nasal/paranasal sinus mucosa in both allergic and non-allergic subjects, the pathogenesis of nasal polyposis remains unknown. Interleukin-17A (IL-17A) is a key inflammatory cytokine in many disorders. Little attention has been paid to the role of IL-17A in chronic inflammatory disorders. OBJECTIVE To investigate the expression of IL-17A in the SNP and verify if this expression is a marker of good or bad prognosis. METHOD Prospective study with 25 patients presenting with SNP were subjected to the immunohistochemistry technique. After a skin prick test, all patients were divided into atopic and nonatopic groups, and asthmatic or non-asthmatic. RESULTS The IL-17A expression was observed in both atopic and nonatopic patients. The numbers of IL-17A positive cells were greater in nasal polyps of atopic patients than nonatopic (p = 0.0128). CONCLUSION These results indicate that IL-17A may play an important role in the pathology of SNP. Considering the inflammatory properties of IL-17A, this study suggests that it could increase susceptibility to atopy and asthma.