Effect of Entamoeba histolytica toxins on isolated human polymorphonuclear leukocytes' phagocytic function.
This study was undertaken to investigate the effect of Entamoeba histolytica toxin (Ehp/t) obtained from HM1:IMSS strain on human polymorphonuclear leukocytes (PMNs) phagocytic function. A less virulent strain, i.e., NIH:200 was also used in this study for comparison. The results revealed that the toxin obtained from the strain HM1:IMSS inhibited the phagocytic activity of PMNs as measured by yeast uptake or chemiluminescence response while the toxin of strain NIH:200 did not show any significant effect. On the other hand, washing of PMNs that had been pre-exposed to the toxin of strain HM1:IMSS failed to reverse the effect of toxin on PMNs. Heat inactivation of the toxin failed to alter its effect on PMNs. Addition of N-acetyl-D-galactosamine (Ga1NAc) to the PMNs did not alter to activity of Ehp/t toxin. These fingdings suggested that Ehp/t toxin might induce similar effect on PMNs of patients infected with ameba.
Al-Tuwaijri
A S
AS
Department of Physiology, College of Medicine, King Saud University, Riyadh, Saudi Arabia.