Xylella fastidiosa gene expression analysis by DNA microarrays

Xylella fastidiosa genome sequencing has generated valuable data by identifying genes acting either on metabolic pathways or in associated pathogenicity and virulence. Based on available information on these genes, new strategies for studying their expression patterns, such as microarray technology, were employed. A total of 2,600 primer pairs were synthesized and then used to generate fragments using the PCR technique. The arrays were hybridized against cDNAs labeled during reverse transcription reactions and which were obtained from bacteria grown under two different conditions (liquid XDM2 and liquid BCYE). All data were statistically analyzed to verify which genes were differentially expressed. In addition to exploring conditions for X. fastidiosa genome-wide transcriptome analysis, the present work observed the differential expression of several classes of genes (energy, protein, amino acid and nucleotide metabolism, transport, degradation of substances, toxins and hypothetical proteins, among others). The understanding of expressed genes in these two different media will be useful in comprehending the metabolic characteristics of X. fastidiosa, and in evaluating how important certain genes are for the functioning and survival of these bacteria in plants

Perfil de citocinas e tipificação de HLA em pacientes com polipose nasossinusal tolerantes e intolerantes a aspirina Cytokines profile and HLA typing in tolerant and non-tolerant patients to aspirin with nasossinusal polyposis

A infiltração eosinofílica do pólipo nasossinusal (PNS) associado à intolerância aspirínica (IA) é característica relevante. Diversos mediadores participam da migração dos eosinófilos para os tecidos. A IA decorre do aumento da síntese de leucotrienos em indivíduos geneticamente susceptíveis. OBJETIVO: Analisar o perfil de citocinas e a tipificação de HLA-A, B e DR em pacientes com PNS tolerantes e intolerantes à aspirina. FORMA DE ESTUDO: Estudo de coorte transversal. MATERIAL E MÉTODO: selecionando-se 45 pacientes: 15 portadores de PNS eosinofílica tolerantes à aspirina (grupo TA); 15 de PNS eosinofílica associada à intolerância aspirínica, manifestada por broncoespasmo (grupo IA) e 15 sem PNS, que apresentavam desvio de septo nasal (grupo controle). O perfil de citocinas (IL-2; IL-4; IL-5; IL-6; IL-8; IL-10; IFN-gama e TNF-alfa) foi pesquisado nos fragmentos de pólipo nasal ou de mucosa de concha média (grupo controle) através da reação reversa da cadeia de polimerase (RT-PCR). A tipificação de HLA-A, B e DR foi realizada através de teste sorológico de microcitotoxicidade ou por amplificação de DNA pela reação em cadeia da polimerase (PCR). RESULTADOS: A expressão de RNAm para as interleucinas 4, 5, 6, 8, 10, IFN-gama e TNF-alfa foi semelhante nos três grupos. A expressão de RNAm para IL-2 associou-se com a IA. Os pacientes portadores dos antígenos A11, B49, DR15 e DR13 apresentaram uma maior probabilidade de desenvolver polipose nasossinusal não relacionada à IA, enquanto os portadores de DR17 apresentaram uma maior probabilidade de desenvolver polipose nasossinusal associada à intolerância aspirínica (Tríade Aspirínica). CONCLUSÃO: A polipose nasossinusal associada à intolerância aspirínica (Tríade Aspirínica) mostrou associação significante com HLA- DR17 e IL-2, sugerindo um perfil de citocinas TH1.<br>The eosinophilic infiltration in the nasosinusal polyp associated with intolerance to aspirin is predominant feature. Several mediators play a role in the migration of the eosinophils to the tissues. The IA may be due to overexpression of leukotrienes in genetically susceptible subjects. AIM: The purpose of this study was to evaluate the cytokine pattern and HLA-A, B and DR typing in subjects with PNS tolerant and intolerants to aspirin. STUDY DESIGN: A transverse cohort study. MATERIAL AND METHOD: was conducted on 45 patients: 15 patients suffering from eosinophilic PNS and aspirin tolerance (group TA); 15 from eosinophilic PNS associated with aspirin intolerance, the latter manifested by bronchospasm (group IA), and 15 without PNS who had nasal septum deviation (control group). Cytokine pattern (IL-2; IL-4; IL-5; IL-6; IL-8; IL-10; IFN-gamma and TNF-alpha) was evaluated in samples from the nasal polyp or midlle turbinate mucosa (control group) of the patients using reverse transcription-polymerase chain reaction (RT-PCR). HLA-A, B and DR typing was performed using the serum microcytotoxicity test or by DNA amplification using polymerase chain reaction (PCR). RESULTS: mRNA expression for interleukines 4, 5, 6, 8, 10, IFN-gamma and TNF-alpha was similar in the three groups. mRNA expression for IL-2 was associated with IA. Patients with antigens A11, B49, DR15 and DR13 had a higher likelihood of developing PNS not-related to intolerance to Aspirin, whereas patients with DR17 had a higher likelihood of developing PNS associated with intolerance to Aspirin (Aspirin Triad). CONCLUSION: PNS associated with intolerance to Aspirin (Aspirin Triad) shows a significant association with HLA- DR17 and IL-2, suggesting a TH1-lymphocyte-activation pattern