BACKGROUND Diabetes mellitus is a systemic condition that has long been associated with an increased risk and severity of periodontal disease. Polymorphonuclear leukocytes (PMNs) play a key role in the maintenance of gingival and periodontal health. Reduced PMN function has been found in patients with diabetes. AIM The objective of this study was to evaluate PMN functions in 15 diabetic patie...

Phagocytosis of microbes coated with opsonins such as the complement component C3bi is the key activity of neutrophils. However, the mechanism by which opsonins enhance the rate of phagocytosis by these cells is unknown and has been difficult to study, partly because of the problem of observing and quantifying the events associated with phagocytosis. In this study, C3bi-opsonized particles were...

This report examined the effect of corticosteroids in vitro on human peripheral blood monocytes, essential cells in both immune and nonimmune cellular defense mechanisms. Monocyte chemotaxis in response to sera, Escherichia coli filtrate, and lymphokine chemotactic factor was markedly reduced (P < 0.01) by hydrocortisone succinate (HCS) at 16 mug/ml. Methylprednisolone succinate and unesterifie...

The formyl peptide receptor 1 (FPR1) is mainly expressed by mammalian phagocytic leukocytes and plays a role in chemotaxis, killing of microorganisms through phagocytosis, and the generation of reactive oxygen species. A large number of ligands have been identified triggering FPR1 including formylated and non-formylated peptides of microbial and endogenous origin. While the expression of FPR1 i...

The hyperglycemic patient remains persistently at risk for infectious complications. Whether ascribable to diabetes mellitus, to the administration of glucocorticoids, or to the infusion of hyperalimentation fluids, hyperglycemia may impair several mechanisms of humoral host defense, including such varied neutrophil functions as adhesion, chemotaxis, and phagocytosis. In addition, binding of gl...

Plasmalemmal phosphatidylinositol (PI) 4,5-bisphosphate (PI4,5P(2)) synthesized by PI 4-phosphate (PI4P) 5-kinase (PIP5K) is key to the polymerization of actin that drives chemotaxis and phagocytosis. We investigated the means whereby PIP5K is targeted to the membrane and its fate during phagosome formation. Homology modeling revealed that all PIP5K isoforms feature a positively charged face. T...

Quantitative leucocyte mobilisation in vivo and the in-vitro random migration, chemotaxis, phagocytosis, and oxidative metabolic activity were studied in 15 patients with rheumatoid arthritis (RA). Patients mobilised leucocytes to chambers covering skin windows to the same degree as control subjects, and the mobilisation correlated with the blood leucocyte numbers and serum concentration of alp...

Vitamin E is the main biological lipid-soluble antioxidant and plays a crucial role in the maintenance of the immune system. In the present work, twenty-one guinea-pigs (3-weeks-old) were distributed into three groups, which during 5 weeks ingested different amounts of vitamin E (/kg diet): 15 mg (low vitamin E diet), 150 mg (medium vitamin E diet; control) or 1500 mg (high vitamin E diet). The...

Surfactant proteins (SP)-A and SP-D have been shown to affect the functions of a variety of innate immune cells and to interact with various immune proteins such as complement and immunoglobulins. The goal of the current study is to test the hypothesis that SP-A regulates IgG-mediated phagocytosis by neutrophils, which are major effector cells of the innate immune response that remove invading ...