Indirtct fluorescent antibody and immobilization tests on Eatamoeba histolytica have been carried out using the sera of 84 Cheju-islanders, a highly endemic area of amebiasis in Korea. The sera were divided into seven groups; 1) liver abscess (E. histolytica in liver), 2) liver abscess (E. histolytica in stool), 3) liver abscess (E. histolytica not demonstrated by examinations of abscess and stool), 4) hepatomegaly (E. histolytica in stool), 5)hepatomegaly (E. histolytica not found in stool), 6) cyst carrier, symptomless healthy individuals and 7) control group. 1. The indirect fluorescent antibody test, 100 per cent of cases with group 1 and group 2, 40 per cent with group 3 and group 4, 33.3 per cent with group 5, 50 per cent with group 6 and 5.9 per cent with control group were found positive at 1:16 or higher. Higher titers were manifested in proved liver abscess, but lower titres were in cyst carrier and control group. 2. The immobilization test, 100 per cent of sera in group 1, 2 and 3, 8O per cent in group 4, 90.5 per cent in group 5, 40 per cent in cyst carrier and 23.5per cent in control group showed positive. 3. Both tests were positive in all sera of group 1 and 2, six sera out of 15 in group 3, four out of 10 in group 4, seven out of 21 in group 5, two out of 10 in cyst carriers and one out of 17 in controls. 4. Indirect F-A titers were not correlated with the rate of immobilization. Therefors it is suggestive that the two methods will be preferable for the diagnosis of suspicious cases of amoebiasis.
Amebiasis/*diagnosis ; Entamoeba histolytica/*immunology ; Female ; Fluorescent Antibody Technique ; Human ; Korea ; Male ; Serologic Tests

Clinico-pathological, parasitological, microbiological and immunologic studies were made in 238 of islanders Cheju, a highly endemic area of amebiasis in Korea. Ameba immobilization test was carried out using immunized rabbit sera and several strains of Entamoeba histolytica. The results are summarized and concluded as follows; I. The number of males with liver abscess was markedly greater than female, and the largest group distribution was observed in ages 30-39. In liver abscess patients, an increase of white blood cells(W.B.C.) and a decrease of red blood cells'R.B.C.) was noted. The differential count of W.B.C. showed an increase of segmented neutrophils and a decrease of 1ymphocytes. The level of total cholesterol and its ester was also diminished, and urobilinogen in patients, urine was increased in comparison with healthy controls. 2. The detection rate for microorganisms in aspirated liver abscess was 42.1%. Most of the recovered microorganisms were Gram negative enteric bacilli; Escherichia coli, Alkaligenes fecalis, Aerobacder aerogenes and paracolon group. Fungi and cocci were not observed. 3. In the immobilization test using immune rabbit sera immunized with a 48-hour-culture of E. histolytica, the highest immobilization reaction occurred 45-105 minutes after the beginning of the test and remobilization of the parasite took place gradually. Immobilization of ameba continued for more hours and at higher rate in the inactivated rabbit sera group, and the differences among ameba strains were not remarkable. In human amebiasis sera, the highest peak of immobilization reaction occurred at 45-90 minutes after testing with the parasite. 4. Positive rates for the immobilization test according to clinical feature were 83.3-100% in liver abscess cases, 83.3-90.7% in hepatomegaly cases, 45.4% in asymptomatic cyst-passers and 31.5% in healthy controls. 5. For 56 patients who showed a high rate of immobilization, the follow-up positive rate after treatment for amebiasis was markedly reduced in 2-3 months.
Adolescent ; Adult ; Animals ; Child ; Entamoeba histolytica/isolation & purification ; Female ; Human ; Korea ; Liver Abscess/*microbiology ; Liver Abscess, Amebic/immunology/*microbiology ; Male ; Middle Aged ; Serologic Tests

Tyrosine kinases are one of the most important regulators for intracellular signal transduction related to inflammatory responses. However, there are no reports describing the effects of tyrosine kinases on neutrophil apoptosis induced by Entamoeba histolytica. In this study, isolated human neutrophils from peripheral blood were incubated with live trophozoites in the presence or absence of tyrosine kinase inhibitors. Entamoeba-induced receptor shedding of CD16 and PS externalization in neutrophils were inhibited by pre-incubation of neutrophils with the broad-spectrum tyrosine kinase inhibitor genistein or the Src family kinase inhibitor PP2. Entamoeba-induced ROS production was also inhibited by genistein or PP2. Moreover, genistein and PP2 blocked the phosphorylation of ERK and p38 MAPK in neutrophils induced by E. histolytica. These results suggest that Src tyrosine kinases may participate in the signaling event for ROS-dependent activation of MAPKs during neutrophil apoptosis induced by E. histolytica.
*Apoptosis ; Cells, Cultured ; Entamoeba histolytica/*immunology/*pathogenicity ; GPI-Linked Proteins/metabolism ; Genistein/metabolism ; Humans ; Neutrophils/*immunology ; Protein Kinase Inhibitors/metabolism ; Pyrimidines/metabolism ; Reactive Oxygen Species/metabolism ; Receptors, IgG/metabolism ; src-Family Kinases/antagonists & inhibitors/*metabolism

This study investigated the effect of breast-feeding in protection against protozoan infection in infants with persistent diarrhea. Infants were classified into 2 groups; 161 breast-fed infants and the same number of non-breast-fed infants. Microscopic examinations of stool were done for detection of parasites and measuring the intensity of infection. Moreover, serum levels of IgE and TNF-alpha were measured by ELISA. Cryptosporidium spp., Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Blastocystis sp. were demonstrated in infants with persistent diarrhea. The percentage of protozoan infections was significantly lower in breast-fed infants than that in the non-breast-fed infants. The levels of IgE and TNF-alpha were significantly lower in the breast-fed group than in the non-breast-fed group. There were significant positive associations between the serum levels of IgE and TNF-alpha and the intensity of parasite infection in the breast-fed group. It is suggested that breast-feeding has an attenuating effect on the rate and intensity of parasite infection.
Antigens, Protozoan/analysis/*immunology ; Diarrhea, Infantile/*diagnosis/parasitology ; Entamoeba ; Entamoeba histolytica/*isolation & purification ; Entamoebiasis/*diagnosis/parasitology ; Enzyme-Linked Immunosorbent Assay ; Feces/parasitology ; Female ; Giardia lamblia ; Giardiasis/*diagnosis/parasitology ; Humans ; Infant ; Intestines/parasitology ; Protozoan Infections/*diagnosis/parasitology ; Tumor Necrosis Factor-alpha/metabolism