Prognostic value of phagocytic activity of neutrophils and monocytes in sepsis. Correlation to CD64 and CD14 antigen expression.

The role of the phagocytic function of monocytes and neutrophils in sepsis has been poorly investigated. The present study evaluated the impact of the phagocytic activity of neutrophils and monocytes on the outcome of patients with severe sepsis. Thirty-one patients and 30 healthy individuals were enrolled in the study. The phagocytic activity of monocytes and neutrophils was evaluated during 24 h after admission and the results were correlated to the expression of CD64 on neutrophils and monocytes, CD14 antigen on monocytes, the Simplified Acute Physiology Score II and the patients' survival. A reduced phagocytic activity of neutrophils during the first 24 h after admission was a negative predictor for survival. Increased expression of CD64 antigen on polymorphonuclear cells (PMNs) and monocytes was favourably correlated to the patients' survival. In multivariate analysis the phagocytic activity of PMNs was the only independent predictor factor for survival. Patients with PMN phagocytic activity <37% had lower expression of CD64 on monocytes and PMNs and worse outcome, while those with phagocytic activity >37% had higher expression of CD64 on monocytes and PMNs and better outcome. Reduced phagocytic activity of neutrophils may represent a state of neutrophil inactivation similar to that previously described for monocytes during the compensatory anti-inflammatory response.

T helper 1 (Th1)/Th2 cytokine expression shift of peripheral blood CD4+ and CD8+ T cells in patients at the post-acute phase of stroke.

Local humoral and cellular immune responses modulate the inflammatory processes involved in the development of atherosclerotic lesions, as well as in the evolution of brain infarcts in stroke patients. The role of systemic adaptive immunity on the progression of such disease manifestations is less clear. In the current study, we evaluated the percentages of T helper 1 (Th1) [interleukin (IL)-2, interferon (IFN)-gamma] and Th2 (IL-4, IL-10) cytokine-producing peripheral blood CD4+ and CD8+ T cells in 23 patients with a history of ischaemic stroke (IS) at the chronic stable phase of the disease (median post-stroke time 34.5 months). Seven stroke-free individuals matched for age and vascular risk factors (matched controls, MC) were collected for comparison. To measure cytokine values at baseline and after stimulation, we used a flow cytometry method of intracellular cytokine staining. Intrinsic Th1 and Th2 cytokine production in unstimulated T cells was negligible in all study participants. Following mitogenic stimulation with phorbol 12-myristate13-acetate/ionomycin, both the IS and the MC groups exhibited a similarly strong Th1 response; IL-2 production predominated in the CD4+ T cells and IFN-gamma in the CD8+ T cells. However, when measuring the Th2 cytokine-production capacity post-stimulation, a significant increase in the percentage of IL-4-producing T cells was observed in the IS groups, compared with the MC group, resulting in a significantly lower ratio of IFN-gamma-/IL-4-producing T cells. No such Th2 enhancement could be confirmed for the case of IL-10. We propose that in IS patients there is a systemic shift of the immune system towards Th2 responses at the late post-acute phase of stroke.

Procleix Ultrio transcription-mediated amplification vs. serological blood screening in south-western Greece.

We present here our overall experience after 27 months of performance of the Procleix Ultrio [HIV-1, hepatitis C virus (HCV), hepatitis B virus (HBV)] transcription-mediated amplification (TMA) assay. The aim of this report is to assess the impact of nucleic acid testing (NAT) implementation in blood screening of south-western Greek blood donors. We processed 38,264 units of blood as neat samples with the Procleix Ultrio TMA assay (Chiron/GenProbe, Emeryville/San Diego, CA, USA) between 1 January 2005 and 31 March 2007. NAT results were compared to those obtained from routine serology tests and quantitative polymerase chain reaction (PCR) assays. Overall, 52 units of blood tested positive for HBV (1.4 per thousand), 8 for HCV (0.2 per thousand) and none for HIV or multiple infections. The yield of TMA was 0.183 per thousand for HBV (7/38 264) and 0 for HCV. The TMA HBV-positive donations were tested for HBV DNA by a quantitative PCR assay and were found negative (below the detection limit of the method, 200 copies/mL). Follow-up testing showed that the TMA HBV-positive donations were positive for anti-hepatitis B core antigen immunoglobulin G antibodies. Implementation of the TMA assay in the individual donation configuration increased HBV detection compared to serological screening or a commonly used quantitative PCR assay. Follow-up studies will determine the impact of NAT implementation in HBV transmission in countries with an intermediate HBV incidence.

Effect of non-operative management (NOM) of splenic rupture versus splenectomy on the distribution of peripheral blood lymphocyte populations and cytokine production by T cells.

Post-traumatic splenectomy is associated with increased postoperative morbidity and mortality and long-term impairment of humoral and cellular immunity. Alternatives to surgery have been developed to minimize or avoid the immediate and/or long-term complications of splenectomy. Herein we investigated the long-term effect of non-operative management (NOM) of the traumatic rupture of the spleen on the distribution of peripheral blood (PB) lymphocyte populations and cytokine production by T cells. PB samples were drawn from six NOM patients, 13 age-matched adults who had undergone splenectomy after trauma (SP patients) and 31 age-matched controls. Cellular phenotypes and the intracellular production of interferon (IFN)-gamma, interleukin (IL)-2, IL-4 and IL-10 cytokines in T cells were determined in whole blood +/- mitogens by flow cytometry. NOM patients did not show any changes in the absolute numbers of lymphocytes or the distribution of their subsets, compared to the controls. In contrast, SP patients showed a sustained increase in the percentage and/or absolute numbers of lymphocytes, CD8 T cells, activated CD8 T cells, natural killer (NK) T cells, NK cells and gammadelta T cells, and a reduction in naive CD4 T cells. The constitutive or induced cytokine production by T cells of the NOM group was similar to the control group, whereas SP patients had increased percentages of constitutive IL-2- and IFN-gamma-producing CD8 T cells and IFN-gamma-producing CD4 T cells. Our findings indicate collectively that the healing process in NOM does not affect the architecture of the spleen to such an extent that it would lead to long-term alterations of the proportions of PB lymphocytes or the T cell cytokine profiles.

In vitro study of the long-term effects of post-traumatic splenectomy on cellular immunity.

The purpose of this study was to investigate the effect of splenectomy on cellular immunity. We studied the cellular phenotype and type 1 [interferon-gamma, interleukin-2 (IL-2)] and type 2 (IL-4 and IL-10) cytokine-producing peripheral blood CD4+ and CD8+ T lymphocytes in 22 healthy adults who had undergone post-traumatic splenectomy about 1 to 35 years ago. Splenectomy resulted in a long-term reduction of the percentage of CD4+CD45RA+ cells and a late increase of the percentage and absolute numbers of T-cell receptor gamma/delta cells. Stimulation with Staphylococcal enterotoxin B resulted in normal IL-2 production by CD4+ T cells, indicating that the naïve cells were not anergic. Splenectomy also resulted in long-term priming of both CD4+ and CD8+ T cells. During the first 8 years, both type 1 and type 2 CD4+ T cells were primed to varying degrees. About 8 years later, the percentage of primed type 2 CD4+ T cells subsided, but that of type 1 CD4+ T cells, although decreased, remained detectable over a longer period. Priming of CD8+ T cells persisted throughout the study period. The long-term priming of type 1 CD4+ and CD8+ T cells, which may result in partial impairment of T-cell functions, may explain reported defects of immune responses to recall antigens in splenectomized individuals. In addition, changes in the profile of primed CD4+ T cells with time may be clinically relevant to relapses in autoimmune thrombocytopenia after splenectomy.