Neutrophils are important effector cells against protozoan extracellular parasite Entamoeba histolytica, which causes amoebic colitis and liver abscess in human beings. Apoptotic cell death of neutrophils is an important event in the resolution of inflammation and parasite's survival in vivo. This study was undertaken to investigate the ultrastructural aspects of apoptotic cells during neutrophil death triggered by Entamoeba histolytica. Isolated human neutrophils from the peripheral blood were incubated with or without live trophozoites of E. histolytica and examined by transmission electron microscopy (TEM). Neutrophils incubated with E. histolytica were observed to show apoptotic characteristics, such as compaction of the nuclear chromatin and swelling of the nuclear envelop. In contrast, neutrophils incubated in the absence of the amoeba had many protrusions of irregular cell surfaces and heterogenous nuclear chromatin. Therefore, it is suggested that Entamoeba-induced neutrophil apoptosis contribute to prevent unwanted tissue inflammation and damage in the amoeba-invaded lesions in vivo.
Animals ; Apoptosis/*physiology ; Entamoeba histolytica/*physiology ; Host-Parasite Relations/physiology ; Humans ; In Vitro ; Neutrophils/physiology/*ultrastructure ; Research Support, Non-U.S. Gov't

Primary ciliary dyskinesia is characterized by chronic upper and lower respiratory infections which are caused by the grossly impaired ciliary transport. Since the cilia and neutrophils both utilize microtubular system for their movement, it has been speculated that neutrophil motility such as chemotaxis might be impaired in patients with primary ciliary dyskinesia. Neutrophils were purified from whole blood from 16 patients with primary ciliary dyskinesia and from 15 healthy controls. Chemotactic responses of neutrophils to leukotriene B4 (LTB4), complement 5a (C5a), and formylmethion-ylleucylphenylalanine (fMLP) were examined using the under agarose method. The chemotactic differentials in response to LTB4, C5a, and fMLP in neutrophils from the patient group were significantly lower than the corresponding values in neutrophils from the control group (p<0.05 for all comparisons). The difference in chemotactic index between the two groups was statistically significant for LTB4 and fMLP (p<0.05 for both comparisons), but not for C5a (p=0.20). Neutrophils from patients with primary ciliary dyskinesia showed a decreased chemotactic response as compared with those from normal subjects. It is concluded that the increased frequency of respiratory tract infection in patients with primary ciliary dyskinesia is possibly due to the defective directional migration of neutrophils, as well as to the defective mucociliary clearance of the airways.
Adolescent ; Chemotactic Factors/pharmacology ; Chemotaxis* ; Child ; Cilia/ultrastructure ; Comparative Study ; Complement 5a/pharmacology ; Dose-Response Relationship, Drug ; Dynein ATPase/chemistry ; Human ; Kartagener Syndrome/blood* ; Kartagener Syndrome/classification ; Leukotriene B4/pharmacology ; Male ; N-Formylmethionine Leucyl-Phenylalanine/pharmacology ; Neutrophils/physiology* ; Neutrophils/ultrastructure

OBJECTIVETo investigate whether the impairment of grafted liver after transplantation was induced by the same inflammatory cells in cold and warm ischemia.

METHODSMale SD rats were divided into two groups randomly, 24 grafted livers in each group were stored for 120 or 240 min at 4 degrees Centigrade Ringer's solution. Also male SD rats were divided into three groups, in which 24 grafted livers in each group were experienced warm ischemia ranged from 90, 120 to 150 min from non-heart-beating donor. The recipients were killed after 1, 3, 6, and 24 hours of transplantation for sample collection.

RESULTSAlong with the prolongation of cold and warm ischemia time, the serum ALT and AST levels were increased gradually after transplantation. Light microscopy showed some necroses in hepatocytes after 3 and 6 hours of transplantation in cold ischemia, and some neutrophilic infiltration in sinusoids. There were a large number of hepatocytes necroses after 3, 6 hours of transplantation in warm ischemia from non-heart-beating donor and a lot of lymphocytic infiltration in sinusoids. The findings in electron microscopy were as the same as those found in light microscopy, and the lymphocytes which infiltrated in sinusoids in warm ischemia were identified as T lymphocytes in electron microscopy.

CONCLUSIONSThe impairment of grafted livers after transplantation seems to be induced by two different inflammatory cells in cold and warm ischemia, that is, neutrophils mediate the cold ischemia-reperfusion, and T lymphocytes mediate the warm ischemia-reperfusion from non-heart-beating donor.

Alanine Transaminase ; blood ; Animals ; Aspartate Aminotransferases ; blood ; Graft Survival ; physiology ; Hepatocytes ; pathology ; ultrastructure ; Liver ; blood supply ; physiopathology ; ultrastructure ; Liver Transplantation ; physiology ; Male ; Neutrophils ; physiology ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; physiopathology ; T-Lymphocytes ; physiology ; Temperature ; Time Factors