Profound peripheral T-lymphocyte depletion and activation in disseminated tuberculosis

Three HIV-1-seronegative patients with disseminated tuberculosis presented significant depletion of T-cell counts, in CD4+ and/or CD8+ cells, associated with increased expression of activation marker CD38 on CD8+ T-lymphocytes. This finding raises the question of potential mechanisms involved in the activation or loss of T-cells in disseminated tuberculosis.Federal University of São Paulo Infectious Diseases DivisionUNIFESP, Infectious Diseases DivisionSciEL

Human monocytes tolerant to LPS retain the ability to phagocytose bacteria and generate reactive oxygen species

Tolerance to lipopolysaccharide (LPS) occurs when animals or cells exposed to LPS become hyporesponsive to a subsequent challenge with LPS. This mechanism is believed to be involved in the down-regulation of cellular responses observed in septic patients. The aim of this investigation was to evaluate LPS-induced monocyte tolerance of healthy volunteers using whole blood. The detection of intracellular IL-6, bacterial phagocytosis and reactive oxygen species (ROS) was determined by flow cytometry, using anti-IL-6-PE, heat-killed Staphylococcus aureus stained with propidium iodide and 2',7'-dichlorofluorescein diacetate, respectively. Monocytes were gated in whole blood by combining FSC and SSC parameters and CD14-positive staining. The exposure to increasing LPS concentrations resulted in lower intracellular concentration of IL-6 in monocytes after challenge. A similar effect was observed with challenge with MALP-2 (a Toll-like receptor (TLR)2/6 agonist) and killed Pseudomonas aeruginosa and S. aureus, but not with flagellin (a TLR5 agonist). LPS conditioning with 15 ng/mL resulted in a 40% reduction of IL-6 in monocytes. In contrast, phagocytosis of P. aeruginosa and S. aureus and induced ROS generation were preserved or increased in tolerant cells. The phenomenon of tolerance involves a complex regulation in which the production of IL-6 was diminished, whereas the bacterial phagocytosis and production of ROS was preserved. Decreased production of proinflammatory cytokines and preserved or increased production of ROS may be an adaptation to control the deleterious effects of inflammation while preserving antimicrobial activity.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Divisão de Moléstias InfecciosasUNIFESP, EPM, Divisão de Moléstias InfecciosasFAPESP: 2006/58744-1SciEL

Lipopolysaccharide-induced expression of cell surface receptors and cell activation of neutrophils and monocytes in whole human blood

Lipopolysaccharide (LPS) activates neutrophils and monocytes, inducing a wide array of biological activities. LPS rough (R) and smooth (S) forms signal through Toll-like receptor 4 (TLR4), but differ in their requirement for CD14. Since the R-form LPS can interact with TLR4 independent of CD14 and the differential expression of CD14 on neutrophils and monocytes, we used the S-form LPS from Salmonella abortus equi and the R-form LPS from Salmonella minnesota mutants to evaluate LPS-induced activation of human neutrophils and monocytes in whole blood from healthy volunteers. Expression of cell surface receptors and reactive oxygen species (ROS) and nitric oxide (NO) generation were measured by flow cytometry in whole blood monocytes and neutrophils. The oxidative burst was quantified by measuring the oxidation of 2',7'-dichlorofluorescein diacetate and the NO production was quantified by measuring the oxidation of 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate. A small increase of TLR4 expression by monocytes was observed after 6 h of LPS stimulation. Monocyte CD14 modulation by LPS was biphasic, with an initial 30% increase followed by a 40% decrease in expression after 6 h of incubation. Expression of CD11b was rapidly up-regulated, doubling after 5 min on monocytes, while down-regulation of CXCR2 was observed on neutrophils, reaching a 50% reduction after 6 h. LPS induced low production of ROS and NO. This study shows a complex LPS-induced cell surface receptor modulation on human monocytes and neutrophils, with up- and down-regulation depending on the receptor. R- and S-form LPS activate human neutrophils similarly, despite the low CD14 expression, if the stimulation occurs in whole blood.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo (UNIFESP) Disciplina de InfectologiaMax-Planck-Institute for ImmunobiologyUNIFESP, Disciplina de InfectologiaFAPESP: 2006/58744-1SciEL

Bloodstream infections in late-stage acquired immunodeficiency syndrome patients evaluated by a lysis centrifugation system

Opportunistic infections, which affect acquired immunodeficiency syndrome (Aids) patients, are frequently disseminated and may cause bloodstream infections (BSI). The aim of this study was to evaluate the main causes of BSI in Aids patients with advanced stage of the disease, with special emphasis on the identification of fungemia. During a 21 months period, all patients with Aids (CD4 < 200) and febrile syndrome admitted to 3 university hospitals were systematically evaluated. For each patient presenting fever, a pair of blood cultures was collected and processed by using a commercial lysis-centrifugation system. One hundred and eleven patients (75 males) with a mean age of 36 years (median 33 years) and mean CD4 count of 64 cells/ml were included. Among the 111 patients evaluated we documented 54 episodes of BSI, including 46 patients with truly systemic infections and 8 episodes considered as contaminants. BSI were caused by gram-positive bacteria (43%), fungi (20%), gram-negative bacteria (15%), mycobacteria (15%), and mixed flora (7%). The crude mortality rate of our patients was 39%, being 50% for patients with BSI and 31% for the others. In conclusion, BSI are a common related to systemic infections on Aids patients with advanced stage of disease and is associated with a high rate of mortality.Universidade Federal de São Paulo (UNIFESP) Hospital São PauloHospital e Maternidade Santa MarcelinaHospital HeliópolisUNIFESP, Hospital São PauloSciEL

Response activity of alveolar macrophages in pulmonary dysfunction caused by Leptospira infection

Leptopspirosis is a syndrome with different clinical manifestations including the most severe and often fatal forms of pulmonary disease of unknown etiology. Pulmonary injury during the inflammatory process has been associated with the excessive number of alveolar macrophages (AMs) and polymorphonuclear leukocytes stimulated in the lungs and with the production of reactive oxygen and nitrogen intermediates and other inflammatory mediators. The aim of the present work was to evaluate the cellular immune response of AMs or inflammatory cells of hamsters during leptospirosis. The activity of AMs was determined by measuring nitric oxide (NO) and protein production as well as inflammatory cell infiltration in bronchoalveolar lavage (BAL) fluid. Pulmonary activity during infection was monitored by measuring pH, pressure of oxygen (PaO2), and pressure of carbon dioxide (PaCO2) in blood samples. Cellular immune response and its role in the genesis of leptospirosis have been incriminated as the main causes of tissue and pulmonary injuries, which consequently lead to the pulmonary dysfunction in severe cases of leptospirosis. The present results show a low production of NO in both supernatant of alveolar macrophage culture and BAL. In the latter, protein production was high and constant, especially during acute infection. Total and differential cell count values were 2.5X10(6) on day 4; 7.3X10(6) on day 21; and 2.3X10(6) on day 28 after infection, with lymphocytes (84.04%) predominating over neutrophils (11.88%) and monocytes (4.07%). Arterial blood gas analysis showed pulmonary compromising along with the infectious process, as observed in parameter values (mean±SD) evidenced in the infected versus control group: PaO2 (60.47mmHg±8.7 vs. 90.09mmHg±9.18), PaCO2 (57.01mmHg±7.87 vs. 47.39mmHg±4.5) and pH (7.39±0.03 vs. 6.8±1.3). Results indicated that Leptospira infection in hamsters is a good experimental model to study leptospirosis. However, some of the immune parameters showed variations which might be associated with the animal species.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)São Paulo State University FOA Microbiology LaboratoryFederal University of São Paulo Division of Geriatric and Gerontology Inflammatory Mediators LaboratoryUNESP FOA Department of Clinics, Surgery and Animal ReproductionUniversidade Federal de São Paulo (UNIFESP) Department of Parasitological and Infectious DiseasesUNIFESP, Division of Geriatric and Gerontology Inflammatory Mediators LaboratoryUNIFESP, Department of Parasitological and Infectious DiseasesSciEL

Efecto de la lidocaína venosa intraoperatoria sobre el dolor e interleucina-6 plasmática en pacientes sometidas a histerectomía

ResumenJustificación y objetivosLa interleucina-6 (IL-6) es predictora de intensidad en el trauma. El objetivo de este estudio fue evaluar el efecto de la lidocaína por vía venosa sobre la intensidad del dolor e IL-6 después de la histerectomía.MétodoEl estudio fue prospectivo, aleatorizado, comparativo y doble ciego en 40 pacientes, entre 18 y 60 años. Fue administrada lidocaína (2mg/kg–1.h–1) en el G1 o solución salina al 0,9% en el G2 durante la operación. La anestesia fue con O2/isoflurano. Se calculó la intensidad del dolor (T0: despertar y 6, 12, 18 y 24h), la primera solicitud de analgésico, y la dosis de morfina en las primeras 24h. La IL-6 se midió antes del inicio de la operación (T0), después de 5h del inicio (T5) y 24h después de finalizada (T24).ResultadosNo hubo diferencia en la intensidad del dolor entre los grupos. Hubo disminución de la intensidad del dolor entre T0 y los otros momentos evaluados en el G1. El tiempo para la primera complementación fue mayor en el G2 (76±104,4min) que en el G1 (26,7±23,3min). No hubo diferencia en las dosis de morfina complementaria entre G1 (23,5±12,6mg) y G2 (18,7±11,3mg). Hubo aumento en las concentraciones de IL-6 en los 2 grupos de T0 para T5 y T24. No hubo diferencia en la dosificación de IL-6 entre los grupos. La concentración de lidocaína fue 856,5±364,1ng/ml–1 en T5 y 30,1±14,2ng/ml–1 en T24.ConclusiónLa lidocaína (2mg/kg–1 /h–1) por vía venosa no generó reducción de la intensidad del dolor y de los niveles plasmáticos de IL-6 en pacientes sometidas a histerectomía abdominal.AbstractBackground and objectivesInterleukin-6 (IL-6) is a predictor of trauma severity. The purpose of this study was to evaluate the effect of intravenous lidocaine on pain severity and plasma IL-6 after hysterectomy.MethodA prospective, randomized, comparative, double-blind study with 40 patients, aged 18-60 years. G1 received lidocaine (2mg.kg−1.h−1) or G2 received 0.9% saline solution during the operation. Anesthesia was induced with O2/isoflurane. Pain severity (T0: awake and 6, 12, 18 and 24hours), first analgesic request, and dose of morphine in 24hours were evaluated. IL-6 was measured before starting surgery (T0), 5hours after the start (T5), and 24hours after the end of surgery (T24).ResultsThere was no difference in pain severity between groups. There was a decrease in pain severity between T0 and other measurement times in G1. Time to first supplementation was greater in G2 (76.0±104.4min) than in G1 (26.7±23.3min). There was no difference in supplemental dose of morphine between G1 (23.5±12.6mg) and G2 (18.7±11.3mg). There were increased concentrations of IL-6 in both groups from T0 to T5 and T24. There was no difference in IL-6 dosage between groups. Lidocaine concentration was 856.5±364.1ng.ml−1 in T5 and 30.1±14.2ng.ml−1 in T24.ConclusionIntravenous lidocaine (2mg.kg−1.h−1) did not reduce pain severity and plasma levels of IL-6 in patients undergoing abdominal hysterectomy

Efeito da lidocaína venosa intraoperatória sobre dor e interleucina‐6 plasmática em pacientes submetidas a histerectomia

ResumoJustificativa e objetivosA interleucina‐6 (IL‐6) é preditora de intensidade no trauma. O objetivo deste estudo foi avaliar o efeito da lidocaína por via venosa sobre a intensidade da dor e IL‐6 após histerectomia.MétodoO estudo foi prospectivo, randomizado, comparativo e duplo‐encoberto em 40 pacientes, entre 18 e 60 anos. Foi administrada lidocaína (2mg.kg–1.h–1) no G1 ou solução salina a 0,9% no G2 durante a operação. A anestesia foi com O2/isoflurano. Foi avaliada a intensidade da dor (T0: despertar e seis, 12, 18 e 24 horas), a primeira solicitação de analgésico, a dose de morfina nas 24 horas. A IL‐6 foi medida antes do início da operação (T0), após cinco horas do início (T5) e 24 horas após o término (T24).ResultadosNão houve diferença na intensidade da dor entre os grupos. Ocorreu diminuição da intensidade da dor entre T0 e os outros momentos avaliados no G1. O tempo para primeira complementação foi maior no G2 (76,0±104,4min) do que no G1 (26,7±23,3min). Não houve diferença na dose de morfina complementar entre G1 (23,5±12,6mg) e G2 (18,7±11,3mg). Houve aumento das concentrações de IL‐6 em ambos os grupos de T0 para T5 e T24. Não houve diferença na dosagem de IL‐6 entre os grupos. A concentração de lidocaína foi 856,5±364,1 ng.mL–1 em T5 e 30,1±14,2 ng.mL–1 em T24.ConclusãoA lidocaína (2mg.kg‐1.h–1) por via venosa não promoveu redução da intensidade da dor e dos níveis plasmáticos de IL‐6 em pacientes submetidas a histerectomia abdominal.AbstractBackground and objectivesInterleukin‐6 (IL‐6) is a predictor of trauma severity. The purpose of this study was to evaluate the effect of intravenous lidocaine on pain severity and plasma IL‐6 after hysterectomy.MethodA prospective, randomized, comparative, double‐blind study with 40 patients, aged 18‐60 years. G1 received lidocaine (2mg.kg−1.h−1) or G2 received 0.9% saline solution during the operation. Anesthesia was induced with O2/isoflurane. Pain severity (T0: awake and 6, 12, 18 and 24hours), first analgesic request, and dose of morphine in 24hours were evaluated. IL‐6 was measured before starting surgery (T0), five hours after the start (T5), and 24hours after the end of surgery (T24).ResultsThere was no difference in pain severity between groups. There was a decrease in pain severity between T0 and other measurement times in G1. Time to first supplementation was greater in G2 (76.0±104.4min) than in G1 (26.7±23.3min). There was no difference in supplemental dose of morphine between G1 (23.5±12.6mg) and G2 (18.7±11.3mg). There were increased concentrations of IL‐6 in both groups from T0 to T5 and T24. There was no difference in IL‐6 dosage between groups. Lidocaine concentration was 856.5±364.1 ng.mL−1 in T5 and 30.1±14.2 ng.mL−1 in T24.ConclusionIntravenous lidocaine (2mg.kg−1.h−1) did not reduce pain severity and plasma levels of IL‐6 in patients undergoing abdominal hysterectomy