Galactosamine [GaIN] inhibits luminol-dependent chemiluminescence of human polymorphonuclear leukocytes

The aim of the present study was to examine the effect of D- galactosamine HCl [GaIN] on the oxidative respiratory burst of isolated human polymorphonuclear leukocyte [PMNs]. GaIN added in vitro to PMNs caused a marked inhibitory effect on the luminol- dependent chemiluminescene [CL] induced by phorbol myristate acetate [PMA] on PMNs. The inhibitory effect produced by GaIN was both dose and time dependent when PMA was used to stimulate the oxidative burst of PMNs. The effect of GaIN on the isolated PMNs was partially irreversible, following washing of the GaIN-treated PMNs with phosphate buffered saline [PBS]. PMNs viability was not significantly altered by incubation with GaIN. Addition of lipopolysaccharide [endotoxin] to isolate PMNs in the presence or absence of GaIN did not alter the oxidative burst of PMNs. Addition of oxygen-free radical scavengers enhanced the inhibitory effect induced by GaIN on PMNs CL. In a cell free medium, GaIN has no inhibitory effect on CL induced by luminol, H2O2 and horse radish peroxidase. As a conclusion, results suggested that in vitro, GaIN has a remarkable inhibitory effect on the release of oxygen products from stimulated PMNs

Function of the polymorphonuclear leukocytes in patients with brucellosis

The aim of the present study was to examine the respiratory burst and phagocytosis of Polymorphonuclear leukocytes [PMNs] function in patients with brucellosis. The PMNs respiratory burst was studied by stimulation with phorbol myristate acetate [PMA] and the chemiluminescence [CL] peak response was measured. Phagocytic activity of PMNs was evaluated by opsonized yeast uptake. Results showed that CL peak response of PMNs was significantly enhanced in patients with non-complicated, and complicated brucellosis, and following treatment for brucellosis. In contrast, the phagocytic activity of PMN [phagocytosis] was markedly inhibited in all groups of patients with brucellosis. The results indicated that infection with Brucella causes alteration of the physiological function of PMNs

Schistosoma mansoni antigenic preparations interfere with normal human polymorphonuclear leukocyte function

The aim of this study was to examine the effects of various forms of Schistosoma mansoni antigens, namely, schistosomulae, soluble egg antigens [SEA] and soluble worm antigenic preparation [SWAP], on the oxidative burst and phagocytosis by normal human polymorphonuclear leukocytes [PMNs]. The PMNs were stimulated with phorbol myristate acetate [PMA] or opsonized yeast [OPY]. Incubation of schistosomulae [10-100] with whole blood or PMNs significantly depressed the oxidative burst of stimulated PMNs as measured by chemiluminescence [CL] technique. Addition of various concentrations of SEA to PMNs directly inhibited phagocytosis of yeast and PMNs-CL response in a time- and concentration-dependent manner. In contrast, SWAP failed to exert any significant inhibition. The inhibitory effect of SEA was shown to be reversible and heat sensitive. Furthermore, schistosoma antigens did not produce a cytotoxic effect on PMNs as determined by the trypan blue exclusion test. The incubation of oxygen scavengers such as superoxide dismutase [SOD] dimethyl sulphoxide [DMS] and catalase with SEA potentiated its inhibitory effect on PMNs-CL. In conclusion, there was a significant inhibition of oxidative burst and phagocytosis by SEA suggesting that a similar effect may occur on PMNs during S. mansoni infection in humans

Inhibition of human polymorphonuclear leukocyte function by lead

In an attempt to evaluate the direct effect of lead [Pb] on the physiological function of polymorphonuclear leukocytes [PMNL], isolated PMNLs were incubated with various concentrations of Pb [1-1000 micro M] for 0, 30, and 60min. The PMNL respiratory burst, phagocytosis and viability were examined in the presence and absence of Pb. The results show that Pb significantly inhibited the PMNL-chemiluminescence [CL] response stimulated with the soluble agent, phorbol myristate acetate [PMA] or a particulate agent, opsonized zymosan [OPZ]. The inhibitory effect of Pb on PMNL-CL responses is concentration, and time-dependent, and irreversible. Additionally, PMNL phagocytosis was significantly reduced when the cells were incubated with various concentrations of Pb. The PMNL viability was not altered when the cells were incubated with low concentrations of Pb [10-100 micro M]. It is concluded that Pb significantly depressed the physiological function of PMNL in vitro