Chemotaxis of mononuclear leukocytes from humans, mink, and cattle was evaluated in vitro using a morphologic Boyden chamber technique and a new labeled mononuclear radioassay with a double micropore filter system. Significantly decreased mononuclear leukocyte chemotactic responses were noted when human, mink, or cattle Chediak-Higashi cells were tested using autologous serum or endotoxin-activ...

We have isolated a UV-induced temperature-sensitive mutant of Mycobacterium smegmatis that fails to grow at 42 degrees C and exhibits a filamentous phenotype following incubation at the nonpermissive temperature, reminiscent of a defect in cell division. Complementation of this mutant with an M. smegmatis genomic library and subsequent subcloning reveal that the defect lies within the M. smegma...

Chemotaxis of mononuclear leukocytes from humans, mink, and cattle was evaluated in vitro using a morphologic Boyden chamber technique and a new 51-Cr-labeled mononuclear radioassay with a double micropore filter system. Significantly decreased mononuclear leukocyte chemotactic response were noted when human, mink, or cattle Chediak-Higashi cells were tested using autologous serum or endotoxin-...

Early events in the human airways determining whether exposure to Mycobacterium tuberculosis (Mtb) results in acquisition of infection are poorly understood. Epithelial cells are the dominant cell type in the lungs, but little is known about their role in tuberculosis. We hypothesised that human primary airway epithelial cells are part of the first line of defense against Mtb-infection and cont...

We describe a case of idiopathic myelofibrosis with total neutrophil myeloperoxidase deficiency. The combination of this enzymatic defect with myelofibrotic changes in the nuclear shape of neutrophils confers a peculiar appearance on leukograms produced by a Technicon H*1. The clinical course of the disease was shortened by recurrent infections that may be ascribed, at least in part, to reduced...

Neutrophil serine proteases, such as cathepsin G (CG) and neutrophil elastase (NE), have been implicated in the protective response against infections, including experimental mycobacterial infections. The goal of this study was to explore the role of CG in immunocompetent mice challenged aerogenically with Mycobacterium tuberculosis. We used genetically CG- or CG/NE-deficient mice to define the...

The physiologic role of L-selectin shedding is unknown. Here, we investigate the effect of L-selectin shedding on firm adhesion and transmigration. In a tumor necrosis factor alpha-induced model of inflammation, inhibition of L-selectin shedding significantly increased firm adhesion and transmigration by a lymphocyte function-associated antigen (LFA)-1 and intercellular adhesion molecule (ICAM)...

Leukocyte recruitment during inflammation is achieved through a multistep paradigm that includes margination, selectin-mediated rolling, beta 2 integrin-mediated firm adhesion, emigration, and migration into the site of inflammation. We have used the mouse cremaster muscle as a model of trauma- and cytokine-induced inflammation to study the possible role of intercellular adhesion molecule (ICAM...

ICAM-2 has been implicated in leukocyte transmigration in vitro, but there is little in vivo evidence to support this. To address this, neutrophil migration was investigated in ICAM-2-deficient mice (KO) and in wild-type (WT) mice treated with an anti-ICAM-2 blocking monoclonal antibody (mAb) (3C4). In a peritonitis model, IL-1beta-induced accumulation of neutrophils was significantly reduced i...

The anti-helminthic drug levamisole hydrochloride has been reported to stimulate immune responses in humans and experimental animals. We have investigated levamisole effects on human leukocyte locomotion in vitro in studies of neutrophils and mononuclear cells from normal adults, from patients with Chediak-Higashi disease and from patients with the syndrome of hyperimmunoglobulin E, recurrent p...