RESUMO
BACKGROUND: We investigated the roles of Toll-like receptors (TLRs) in naturally occurring influenza. METHODS: A prospective, case - control study was conducted. Adults hospitalized with virologically confirmed influenza A infections (onset <48 hours, before treatment) were compared with age-/gender-matched controls. TLRs (2, 3, 4, 7, 8, 9) expression in monocytes and dendritic cells (DCs - total, myeloid, plasmacytoid) was quantitated using flow cytometry. Gene expression of RLRs (RIG-1, MDA-5) was evaluated using real-time PCR. Concomitant signaling molecules expression, plasma cytokine/chemokine concentrations, and respiratory tract viral loads were measured. PBMCs were cultured and stimulated ex vivo with TLR-specific ligands for cytokine responses. RESULTS: Forty two patients with influenza (24 A/H3N2, 18 A/H1N1pdm09) and 20 controls were studied. Patients' mean age was 68 ± 16 years; 81% had respiratory/cardiovascular complications. There were increased cellular expressions of TLR9, TLR8, TLR3, and TLR7 during influenza; TLR2 and TLR4 were suppressed. Results were similar for both virus strains. Higher TLR expression levels at presentation significantly correlated with lower viral loads (Spearman's rho: -0.46 to -0.69 for TLR9, TLR8, and TLR3; P-values <0.05). Multivariate regression models (adjusted for age, comorbidity, disease severity, time from onset) confirmed their independent associations. Increased signaling molecules (phospho-MAPKs, IκB) and inflammatory cytokines (IL-6, sTNFR-1, CCL2/MCP-1; CXCL10/IP-10, IFN-γ) correlated with increased TLR expression. RLRs were upregulated simultaneously. PBMCs of patients with influenza showed significant, dynamic changes in their cytokine responses upon TLR stimulation, compared with controls. CONCLUSIONS: Our results suggest that TLRs play an important role in early, innate viral inhibition in naturally occurring influenza. Inflammatory cytokine responses are concomitantly induced. These findings support investigation of TLR targeting as a novel intervention approach for prophylaxis against influenza.
Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/imunologia , Receptores Toll-Like/imunologia , Adulto , Idoso , Estudos de Casos e Controles , Citocinas/genética , Citocinas/imunologia , Células Dendríticas/imunologia , Feminino , Hospitalização , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/genética , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Receptores Toll-Like/genéticaRESUMO
Co-stimulatory molecules together with leukocyte adhesion molecules are important for T lymphocyte and leukocyte-mediated inflammatory responses. We investigated the soluble costimulatory molecules CD80, CD86, CD28, and CTLA-4 and soluble adhesion molecules in plasma of 94 type 2 diabetic patients with or without nephropathy (DN and NDN) and 20 healthy controls. Plasma concentration of sCTLA-4 was significantly lower, whereas sCD28 was significantly higher in DN patients than that in control subjects (all P < 0.05). sCD28 and sCD80 were found to be positively correlated with fasting urine albumin: creatinine ratio in DN patients but not in NDN patients. Elevated soluble adhesion molecule vascular cell adhesion molecule-1 and P-selectin could be related with the disease severity of DN (all P < 0.05). Therefore, the aberrant expression of soluble co-stimulatory molecules and adhesion molecules can be related to the activation of T cells and leukocytes in the progression of inflammation in diabetic nephropathy.
