RESUMO
This study investigated the association of tumor necrosis factor-α (TNF-α)-308, -238, and -863 polymorphisms with osteoarticular tuberculosis (OA-TB) prognosis in a Hebei population. Genomic DNA was extracted from venous blood samples of 120 OA-TB patients and 100 healthy volunteers. TNF-α-308, -238, and -863 were analyzed by PCR-restriction fragment length polymorphism; genotype and allele frequencies were calculated. Serum TNF-α level was significantly higher in OA-TB patients (283.16 ± 51.68 ng/L) than in control (122.54 ± 54.65 ng/L; P < 0.05). Higher frequency of TNF-α-308 GG genotype in healthy volunteers (91.0%) than in OA-TB patients (79.2%) indicated that it was a protective factor against OA-TB (OR = 0.405, 95%CI = 0.147-0.657, P = 0.007). Higher frequencies of TNF-α-308 GA genotype and TNF-α-308 allele (A) in OA-TB patients (20.8 and 10.4%, respectively) than in healthy volunteers (8.0 and 5.0%, respectively) indicated an association with increased risk of OA-TB (OR = 3.112, 95%CI = 1.520-6.343, P = 0.003; OR = 3.109, 95%CI = 1.676-6.538, P = 0.006; respectively). Haplotype association analysis of TNF-α polymorphisms (-308/-238/-863) showed a higher frequency of TNF-α AGA in OA-TB patients (12.1%) than in healthy volunteers (3.5%), indicating that it was a risk factor for OA-TB (OR = 4.201, 95%CI = 1.80-9.91, P = 0.010). TNF-α-308 G/A and TNF-α AGA (-308/-238/-863) were associated with a predisposition to OA-TB, which could aid clinical detection, prevention, and prognosis of OA-TB.
Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Tuberculose Osteoarticular/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Alelos , Feminino , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico , Fatores de Risco , Tuberculose Osteoarticular/patologiaRESUMO
To identify the linear epitope for Fc-binding to the mouse immunoglobulin G (IgG) Fc receptor (moFcγRI), peptides derived from the membrane-distal extracellular domain (EC2) of moFcγRI, corresponding to the homologous region of human FcγRI (huFcγRI) and huFcγRII, were synthesized. Using a dot-blot assay, six peptides were tested. The results showed that the moRI3 peptide (CVFYRNGKSFQFS) could combine with mouse IgG efficiently. A competitive enzyme-linked immunosorbent assay (ELISA) showed that the IC50 value of the moRI3 peptide was 38.03 mM. The moRI3 peptide could inhibit the combination of mouse IgG to the transfected COS 7 cells significantly with an IC50 value of 72.68 mM. The IgG-binding region of moFcγRI was also localized in the C'-E loop of the EC2 domain as predicted according to huFcγRI and huFcγRII. We predicted that the minimum effective IgG-binding region of moFcγRI may be the peptide 153SFQFSS158. The linear epitope for immunoglobulin-binding to mouse FcγR is also described. Thus, we generated a peptide that targets a fundamental aspect of ligand recognition by this receptor class.