Evaluation of Toll-like, chemokine, and integrin receptors on monocytes and neutrophils from peripheral blood of septic patients and their correlation with clinical outcomes

Recognition of pathogens is performed by specific receptors in cells of the innate immune system, which may undergo modulation during the continuum of clinical manifestations of sepsis. Monocytes and neutrophils play a key role in host defense by sensing and destroying microorganisms. This study aimed to evaluate the expression of CD14 receptors on monocytes; CD66b and CXCR2 receptors on neutrophils; and TLR2, TLR4, TLR5, TLR9, and CD11b receptors on both cell types of septic patients. Seventy-seven septic patients (SP) and 40 healthy volunteers (HV) were included in the study, and blood samples were collected on day zero (D0) and after 7 days of therapy (D7). Evaluation of the cellular receptors was carried out by flow cytometry. Expression of CD14 on monocytes and of CD11b and CXCR2 on neutrophils from SP was lower than that from HV. Conversely, expression of TLR5 on monocytes and neutrophils was higher in SP compared with HV. Expression of TLR2 on the surface of neutrophils and that of TLR5 on monocytes and neutrophils of SP was lower at D7 than at D0. In addition, SP who survived showed reduced expression of TLR2 and TLR4 on the surface of neutrophils at D7 compared to D0. Expression of CXCR2 for surviving patients was higher at follow-up compared to baseline. We conclude that expression of recognition and cell signaling receptors is differentially regulated between SP and HV depending on the receptor being evaluated.

Induction of interleukin-10 by HIV antigens in peripheral mononuclear cells of health care workers after occupational exposure to HIV-1-positive blood

Evaluation of HIV-induced IL-2 production by peripheral blood mononuclear cells (PBMC) and HIV-specific T helper and cytotoxic T lymphocyte (CTL) responses in health care workers (HCW) occupationally exposed to HIV reveals a high rate of response to HIV among non-seroconverters. IL-10 is also known to interfere with HIV infection in vitro. To evaluate the induction of IL-10 by HIV antigens in HCW occupationally exposed to HIV, 18 HCW with percutaneous injury were enrolled in this study, 9 of them exposed to HIV-contaminated blood, and 9 exposed to HIV-negative blood. PBMC were incubated on plates coated with HIV-1 antigens, and IL-10 was measured in supernatants by ELISA. Five of nine HCW exposed to HIV-contaminated blood presented HIV-induced IL-10. Two of nine HCW exposed to HIV-negative source patients also had detectable levels of HIV-induced IL-10, one of them in the sample obtained on the day of accidental exposure. There was a relationship between the type of device involved in injury and IL-10 production. Individuals exposed to hollow needles or scalpels presented HIV-induced IL-10, whereas those exposed to solid needles and to digital puncture did not, suggesting a relationship between infectious load and IL-10. Although occupational exposure to HIV leads to a low rate of seroconversion, these individuals can develop an antigen-specific immune response characterized in our study by induction of IL-10 in PBMC in vitro

Estudo caso-controle da infecçäo pelo HIV em pacientes em programa de hemodiálises / Control case study of HIV infection in dialysis patients

O Brasil é o quarto país no mundo em número de casos de AIDS, apresentando elevada proporçäo da doença adquirida através de transfusäo de sangue. Uma vez que os pacientes com insuficiência renal crônica em programa de hemodiálise säo freqüentemente submetidos a transfusöes sanguíneas, constituem-se em grupo com risco potencial de exposiçäo ao HIV. Estudou-se a prevalência de infecçäo pelo HIV em 117 pacientes em programa de hemodiálise na Casa de Saúde Santa Marcelina, identificando-se nove (7,7%) pacientes soropositivos pelos métodos ELISA e Western Blot. Nenhum paciente tinha outro fator de risco para infecçäo, além das transfusöes. Cada pacientes soropositivo foi comparado com três controles soronegativos, pareados por sexo. O número médio de transfusöes foi de 29,3 unidades para os casos e 26,7 unidades para os controles. O tempo médio de diálise foi de 28,2 e 27,2 meses para casos e controles, respectivamente. O risco de infecçäo pelo HIV näo foi associado ao número de transfusöes ou ao tempo de diálise. A relaçäo OKT/OKT foi menor ou igual a um em todos os pacientes infectados