BACKGROUND The words 'infection' and 'inflammation' lack specific definitions. Here, such words are not defined. Instead, the ability to visualize host-microbial interactions was explored. METHODS Leukocyte differential counts and four bacterial species (Staphylococcus aureus, Streptococcus dysgalactiae, Staphylococcus chromogenes, and Escherichia coli) were determined or isolated in a cross-...

Monocytes from 19 of 30 patients with the classic phenotype of chronic granulomatous disease of childhood (CGD) responded to 3 days of treatment in culture with recombinant human interferon-gamma (rHuIFN-gamma) at 100 units/ml by producing superoxide after stimulation with phorbol 12-myristate 13-acetate. Cells from 15 of 16 patients with cytochrome b-positive CGD (15 with autosomal and 1 with ...

Mononuclear-phagocyte system plays an important role in natural immunity and nonspecific resistance reactions of the organism against infection. The experimental studies using conventional laboratory animals with uncontrolled microflora have certain limitations to fully appreciate the role of autoflora (microbiota) in both development and functional activity of mononuclear-phagocyte system. In ...

Dendritic cells (DC) are mononuclear phagocytes which exhibit a branching (dendritic) morphology and excel at naïve T cell activation. DC encompass several subsets initially identified by their expression of cell surface molecules and later shown to possess distinct functions. DC subset differentiation is orchestrated by transcription factors, growth factors and cytokines. Identifying DC subset...

INTRODUCTION Phagocytosis is the critical first step in the Mycobacterium (M.) tuberculosis-phagocyte interaction. The process involves microbial ligands and phagocyte surface receptors. It is known that serum mannose-binding lectin (MBL), an innate immune system component, may enhance the uptake of microbes by phagocytic cells and activate the complement system. Since phagocytes are the replic...

Pseudomonas aeruginosa is an opportunistic human pathogen that can cause serious infection in those with deficient or impaired phagocytes. We have developed the optically transparent and genetically tractable zebrafish embryo as a model for systemic P. aeruginosa infection. Despite lacking adaptive immunity at this developmental stage, zebrafish embryos were highly resistant to P. aeruginosa in...

Many brain diseases involve activation of resident and peripheral immune cells to clear damaged and dying neurons. Which immune cells respond in what way to cues related to brain disease, however, remains poorly understood. To elucidate these in vivo immunological events in response to brain cell death we used genetically targeted cell ablation in zebrafish. Using intravital microscopy and larg...

Phagocyte-derived reactive oxygen species have been implicated in the clearance of malaria infections. We investigated the progression of five different strains of murine malaria in gp91(phox-/-) mice, which lack a functional NADPH oxidase and thus the ability to produce phagocyte-derived reactive oxygen species. We found that the absence of functional NADPH oxidase in the gene knockout mice ha...

Schistosoma blood flukes, which infect over 200 million people globally, co-opt CD4+ T cell-dependent mechanisms to facilitate parasite development and egg excretion. The latter requires Th2 responses, while the mechanism underpinning the former has remained obscure. Using mice that are either defective in T cell receptor (TCR) signaling or that lack TCRs that can respond to schistosomes, we sh...