Elevated postinjury thrombospondin 1-CD47 triggering aids differentiation of patients' defective inflammatory CD1a+dendritic cells.

A subset of Pts develops dysfunctional MO to inflammatory DC differentiation and immunosuppression. MDDC, a newly described DC subset, is pivotal in initiating antibacterial responses. Endogenous proteins are known to alter MO to MDDC differentiation.

Trauma-associated human neutrophil alterations revealed by comparative proteomics profiling.

Purpose: Polymorphonuclear neutrophils (PMNs) play an important role in mediating the innate immune response after severe traumatic injury; however, the cellular proteome response to traumatic condition is still largely unknown.

Experimental Design: We applied 2D-LC-MS/MS-based shotgun proteomics to perform comparative proteome profiling of human PMNs from severe trauma patients and healthy controls.

Results: A total of 197 out of ~2500 proteins (being identified with at least two peptides) were observed with significant abundance changes following the injury.

Trauma patients' elevated tumor necrosis related apoptosis inducing ligand (TRAIL) contributes to increased T cell apoptosis.

Immunosuppression resulting from excessive post-trauma apoptosis of hyperactivated T cells is controversial. TRAIL mediated T cell apoptosis decreases highly activated T cells' responses. Caspase-10, a particular TRAIL target, was increased in trauma patients' T cells with concomitantly elevated plasma TRAIL levels.

Heat shock protein 27 differentiates tolerogenic macrophages that may support human breast cancer progression.

Tumor cells release several factors that can help the progression of the tumor by directly supporting tumor growth and/or suppressing host antitumor immunity. Here, we report that human primary breast tumor cells not only express elevated levels of heat shock protein 27 (Hsp27) at the intracellular level but also release extremely high levels of Hsp27 compared with the same patients' serum Hsp27 levels, predicting an acutely increased concentration of soluble Hsp27 in the human breast tumor microenvironment (HBTM). We demonstrate that Hsp27 levels in the HBTM can be extremely elevated as evidenced by high soluble Hsp27 levels in patients' tumor interstitial fluid.

Identification and interpretation of longitudinal gene expression changes in trauma.

Rationale: The relationship between leukocyte gene expression and recovery of respiratory function after injury may provide information on the etiology of multiple organ dysfunction.

Objectives: To find a list of genes for which expression after injury predicts respiratory recovery, and to identify which networks and pathways characterize these genes.

Methods: Blood was sampled at 12 hours and at 1, 4, 7, 21 and 28 days from 147 patients who had been admitted to the hospital after blunt trauma.

Analysis of factorial time-course microarrays with application to a clinical study of burn injury.

Time-course microarray experiments are capable of capturing dynamic gene expression profiles. It is important to study how these dynamic profiles depend on the multiple factors that characterize the experimental condition under which the time course is observed. Analytic methods are needed to simultaneously handle the time course and factorial structure in the data.

Cytokine induced expression of programmed death ligands in human neutrophils.

Recent evidence indicates that human neutrophils can serve as non-professional antigen presenting cells (APC). Although expression of MHC class II and co-stimulatory molecules on human neutrophils is limited, these molecules can be significantly induced following in vitro exposure to the cytokines IFNgamma and GM-CSF. Since professional APCs such as dendritic cells express both co-stimulatory and co-inhibitory molecules for activation and regulation of adaptive immunity, we determined whether cytokines induce increased expression of specific co-signaling molecules on human neutrophils.

Acetaldehyde stimulates monocyte adhesion in a P-selectin- and TNFalpha-dependent manner.

Objective: The aim of this study was to determine the effects of acetaldehyde on various steps of the monocyte recruitment cascade.

Methods: Human umbilical venous endothelial cells (HUVEC), primary blood monocytes (PBM) and THP-1 monocytes, were treated with acetaldehyde (0.1-0 microM) for 6h.

HSP27: an anti-inflammatory and immunomodulatory stress protein acting to dampen immune function.

The effects of HSP27 on human monocytes (MO) are predominantly antiinflammatory through preferential interleukin (IL)10 induction and by alteration of MO to immature dendritic cells (iDCs) or MO to macrophage (Mac) differentiation. Initial HSP27 inclusion in IL4+GM-CSF MO to iDC induction cultures allows Mac differentiation (CD14++, CD16+), decreases iDC (CD1a+) differentiation, and depresses DC induction of allogeneic T lymphocyte proliferation (MLR). HSP27 increased MO IL10 and M-CSF production but subsequent increased Mac differentiation isn't responsible for depressed MO to iDC differentiation and function.

Selective activation of peripheral blood T cell subsets by endotoxin infusion in healthy human subjects corresponds to differential chemokine activation.

Although activation of human innate immunity after endotoxin administration is well established, in vivo endotoxin effects on human T cell responses are not well understood. Most naive human T cells do not express receptors for LPS, but can respond to endotoxin-induced mediators such as chemokines. In this study, we characterized the in vivo response of peripheral human T cell subsets to endotoxin infusion by assessing alterations in isolated T cells expressing different phenotypes, intracellular cytokines, and systemic chemokines concentration, which may influence these indirect T cell responses.

Development of a simple method for rapid isolation of polymorphonuclear leukocytes from human blood.

Polymorphonuclear leukocytes (PMNs; commonly known as neutrophils) play essential roles in innate immunity and inflammation. Although there are standardized methods for the isolation of human neutrophils, they are time consuming and demand considerable technical expertise, making them unfeasible for many clinical applications. Here, we describe a simple and time-efficient technique for the isolation of human neutrophils, which adapts a readily available commercial cell preparation tube (CPT) currently in use for isolation of peripheral blood mononuclear cells (PBMC) and plasma and is now adapted to also yield neutrophils.

Whole blood and leukocyte RNA isolation for gene expression analyses.

The analysis of gene expression data in clinical medicine has been plagued by the lack of a critical evaluation of accepted methodologies for the collection, processing, and labeling of RNA. In the present report, the reliability of two commonly used techniques to isolate RNA from whole blood or its leukocyte compartment was compared by examining their reproducibility, variance, and signal-to-noise ratios. Whole blood was obtained from healthy subjects and was either untreated or stimulated ex vivo with Staphylococcus enterotoxin B (SEB).

Failure of monocytes of trauma patients to convert to immature dendritic cells is related to preferential macrophage-colony-stimulating factor-driven macrophage differentiation.

Following trauma, increased inflammatory monokine activation and depressed APC function can occur simultaneously. These contradictory monocyte (Mphi) dysfunctions could result if postinjury Mphi differentiation preferentially favored inflammatory macrophage (Mac) differentiation over development into the most potent APC, dendritic cells (DC). In this report, Mphi of trauma patients with a depressed MLR induction capacity are, for the first time, shown to be unable to differentiate in vitro to immature CD1a(+) DC under the influence of GM-CSF and IL-4.