A total of 377 pregnant women, 43 pelvic tumor patients and 80 of multiphysic health center persons as controls were examined by indirect latex agglutination test in order to evaluate Toxoplasma antibody titers at Kang-Nam St. Mary's Hospital in Seoul. Throughout this survey, 1:32 or more titers of diluted sera were regarded as positive. The 337 samples of test sera in pregnant women showed negatives in 319 cases (84.6 percent), 1:2 in 44 cases (11.7 percent), 1:4 in 9 cases (2.4 percent), 1:8 in 2 cases (0.5 percent), 1:16 in 1 case (0.3 percent) and 1:32 in 2 cases (0.5 percent) respectively. The 43 samples of test sera in pelvic tumor patients showed negatives in 29 cases (67.4 percent), 1:2 in 8 cases (18.6 percent), 1:4 in 1 case (2.3 percent), 1:16 in 2 cases (4.7 percent), 1:32 in 1 case (2.3 percent) and 1:128 in 2 cases (4.7 percent). The 80 samples of test sera in multiphysic health center persons as controls negatives in 56 cases (70.0 percent), 1:2 in 19 cases (23.8 percent), 1:4 in 3 cases (3.8 percent), 1:8 in 1 case (1.3 percent) and 1:128 in 1 case (1.3 percent). Among total 420 study cases, 5 cases (1.2 percent) showed positives , and they were 2 cases (0.5 percent) of pregnant women and 3 cases (7.0 percent) of pelvic tumor patients. One case (1.3 percent) out of 80 control sera showed positive result.
parasitology-protozoa ; Toxoplasma gondii ; diagnosis ; immunology

A total of 421 patients hospitalized in St. Mary's Hospital were examined by indirect latex agglutination test in order to evaluate the Toxoplasma antibody in Korean from June to August 1981. The test sera of the patients were obtained from each age group by random sampling. The 421 samples of test sera showed negative in 153, 1:2 in 157, 1:4 in 59, 1:8 in 27, 1:16 in 7, 1:32 in 9, 1:64 in 2, 1:128 in 4 and 1:256 in 3 cases, respectively. The positive rate of Toxoplasma antibody was 4.3 percent in this sample when indirect latex antibodies of 1:32 or higher were regarded as positive. The titers of positive Toxoplasma antibodies were increased by age.
parasitology-protozoa ; Toxoplasma gondii ; toxoplasmosis ; immunology ; diagnosis

Serological studies on toxoplasmosis were conducted with rabbits sera that were immunized with RH strain or infected with Beverley strain of Toxoplasma gondii. Complement fixation tests, agar-gel double diffusion tests and agar-gel immunoelectrophoresis were performed. Toxoplasma crude antigen was prepared from the organisms in mice peritoneal fluids, which were infected with RH strain of Toxoplasma gondii. The organisms were suspended in saline volume originally exudated and counted in hemocytometer for purity of the organisms over 99 per cent. These suspended organisms were prepared by sonication, and the solution was centrifuged for 30 min. at 10,000 rpm in 4C. These supernatant fluids were used as crude antigen. On the other hand, purified antigens were fractionated on Sephadex G-200 gel filtration. A Sephadex G-200 column, 80 by 4 cm, equilibrated with Tris-HCl-(0.1 M)-NaCl (1.0 M) buffer, pH 8.0 was used. The eluate fractions were collected in 3 ml per hour and the absorbance at 280 nm was measured with a Beckman Du-2 spectrophotometer. Each tube is pooled into 6 fractions by protein density graph. For immunization of rabbits, crude antigen of RH strain was emulsified with an equal amount of incomplete Freund's adjuvant and l ml of mixture was injected subcutaneously into them once a week for 5 successive weeks. Antisera were obtained at an interval of a week, beginning the first week after the last immunization, while several rabbits were infected with Beverley strain of Toxoplasma gondii by inoculating about 200 cysts and antisera were obtained from them serially at a week interval. The results were as follows: The sera from the rabbits immunized with the RH strain or infected with Beverley strain of Toxoplasma gondii againist the crude antigen showed the first positive reactions in 2 or 3 weeks after the administration or immunization in complement fixation tests. Maximum titers appeared in 4 or 5 weeks after immunization with RH strain and in 7 or 9 weeks after infection with Beverley strain respectively. Complement fixation tests showed the positive reactions in the rabbits sera immunized with RH strain against the purified antigens II, III, IV, V and VI: moreover, antigen IV fraction showed the highest titer. On the other hand in the rabbits sera infected with Beverley strain against the purifed antigens II, III and IV fractions showed the positive reaction; especially, antigen fraction IV showed the highest titer. In immuno-diffusion tests, the sera from the rabbits immunized with RH strain and infected with Beverley strain, against the crude antigen appeared the precipitin bands 2 weeks after the immunization or infection. And the former showed the 2 or 5 precipitin bands after 5-8 weeks and the latter showed the l or 2 precipitin bands after 6 weeks. The sera from the rabbits immunized with RH strain against the purified antigens II, III, IV,V and VI showed the precipitin bands, and the sera from the rabbits infected with Beverley strain against the purified antigens II, III and IV showed the precipitin bands in the immuno-diffusion tests. Especially antigen IV was the strongest reaction against the sera from RH strain and Beverley strain. In agar-gel immunoelectrophoresis, the immunized sera against the crude antigen showed 8 arcs. But the infected sera against the crude antigen showed 4 or 5 arcs. The immunized sera against the fractionated antigens II, III, IV, V, VI showed arcs, but against the fractionated antigen IV showed 6 arcs and in the antigens II, III, V, VI showed l or 2 arcs only. On the other hand, the infected sera against the fractionated antigens IV showed 4 arcs, II and III showed the l arcs, which was the most weak of all.
parasitology-protozoa-Toxoplasma gondii ; toxoplasmosis ; rabbit ; immunology ; electrophoresis

Field rodents involved in ecological food chains and which are the prey of carnivores in the natural environment may serve as reservoir hosts for Toxoplasma gondii infection in humans, however, no data has been published to date in Korea. A total of 1,008 Apodemus agrarius, a dominant species of field rodents in Korea, were trapped at various locations around the country, and their serum antibody (IgG) levels to T. gondii were examined by ELISA. The mean absorbance was 0.11, and fifteen samples (1.49%) showed positive titers from 0.18 to 0.59. The seropositive samples were analyzed by immunoblot. Five of them showed reactive bands to T. gondii water soluble antigens of 30, 35, and 43 kDa. This immunoblot analysis showed very similar patterns to that obtained using sera of experimentally infected mice with T. gondii. The present study presents indirect evidence of the existence of T. gondii in field rodents in Korea.
Animal ; Antibodies, Protozoan/blood* ; Antigens, Protozoan/immunology ; Enzyme-Linked Immunosorbent Assay ; Immunoblotting ; Molecular Weight ; Muridae/parasitology* ; Seroepidemiologic Studies ; Toxoplasma/isolation & purification* ; Toxoplasma/immunology

IL-23 and IL-12 are structurally similar and critical for the generation of efficient cellular immune responses. Toxoplasma gondii induces a strong cell-mediated immune response. However, little is known about IL-23 secretion profiles in T. gondii-infected immune cells in connection with IL-12. We compared the patterns of IL-23 and IL-12 production by THP-1 human monocytic cells in response to stimulation with live or heat-killed T. gondii tachyzoites, or with equivalent quantities of either T. gondii excretory/secretory proteins (ESP) or soluble tachyzoite antigen (STAg). IL-23 and IL-12 were significantly increased from 6 hr after stimulation with T. gondii antigens, and their secretions were increased with parasite dose-dependent manner. IL-23 concentrations were significantly higher than those of IL-12 at the same multiplicity of infection. IL-23 secretion induced by live parasites was significantly higher than that by heat-killed parasites, ESP, or STAg, whereas IL-12 secretion by live parasite was similar to those of ESP or STAg. However, the lowest levels of both cytokines were at stimulation with heat-killed parasites. These data indicate that IL-23 secretion patterns by stimulation with various kinds of T. gondii antigens at THP-1 monocytic cells are similar to those of IL-12, even though the levels of IL-23 induction were significantly higher than those of IL-12. The detailed kinetics induced by each T. gondii antigen were different from each other.
Antigens, Protozoan/*immunology ; Cell Line ; Humans ; Interleukin-12/*secretion ; Interleukin-23/*secretion ; Monocytes/*immunology/*parasitology ; Time Factors ; Toxoplasma/*immunology

OBJECTIVETo prepare and characterize rabbit polyclonal antibodies against Toxoplasma gondii vacuolar proton pyrophosphatase type I (TgVP1).

METHODS AND RESULTSTwo synthesized peptides TgVP1-1 and TgVP1-2 as the haptens were conjugated with KLH to immunize rabbits. Indirect ELISA showed that the titers of rabbit anti-TgVP1-1 polyclonal antibody and rabbit anti-TgVP1-2 polyclonal antibody reached 1:128 000. Western blotting results revealed that both purified polyclonal antibodies could specifically bind to a purified 85 kD T. gondii protein predicted as TgVP1. The protein detected by these two polyclonal antibodies was distributed in the cytoplasm of T. gondii tachyzoite, and this distribution pattern was consistent with that of acidocalcisome.

CONCLUSIONThe peptide-based method of antibody generation is efficient and the obtained TgVP1 polyclonal antibodies possess a high specificity to facilitate further study of T. gondii acidocalcisome and the diagnosis of toxoplasmosis.

Animals ; Antibodies ; immunology ; Blotting, Western ; Enzyme-Linked Immunosorbent Assay ; Protozoan Proteins ; immunology ; Pyrophosphatases ; immunology ; Rabbits ; Toxoplasma ; enzymology

A total of 573 patients hospitalized in National Seoul Mental Hospital and 76 of healthy persons as control were examined by indirect latex agglutination test in order to evaluate Toxoplasma antibody titers in mental patients. Throughout this survey, 1:32 or more titers of diluted sera were regarded as positive. The 573 samples of test sera showed negative in 386 cases (67.4 percent), 1:2 in 93 cases (16.2 percent), 1:4 in 57 cases (9.9 percent), 1:8 in 14 cases (2.4 percent), 1:16 in 12 cases (2.1 percent), 1:32 in 5 cases (0.9 percent), 1:64 in 1 case (0.2 percent), 1:128 in 3 cases (0.5 percent) and 1:256 in 2 cases (0.3 percent) respectively. Among total 573 mental patients, 11 cases (19 percent) showed positive, and they were 9 cases (1.8 percent) of schizophrenia and 2 cases (7.4 percent) of manic depression. One case (1.3 percent) out of 76 control sera showed positive result.
parasitology-protozoa ; Toxoplasma gondii ; immunology ; indirect latex agglutination test ; schizophrenia ; manic depression

The development of antibody titers and cross reation between Sarcocystis and Toxoplasma were investigated by means of IFA test and ELISA in pigs experimentally infected with 1.5 x 10(6) S. suicanis sporocysts and 10,000 T. gondii oocysts, respectively. The intact and soluble Sarcocystis antigens were prepared from the bradyzoites harvested by peptic digestion of infected pork. The intact and soluble Toxoplasma, antigens were prepared from the tachyzoites in mouse peritoneal cavity. IgG antibodies in pigs infeded with Sarcocystis and Toxoplasma, respectively were detected first at 2 weeks post infection on both IFA test and ELISA. The antibody titer to Toxoplasma reached its maximum at 6 weeks post infection and decreased thereafter. The antibody titer to Sarcocystis reached its maximum terminally. The cross-reaction titer in pigs infected with Toxoplasma against Sarcocystis antigen was up to 1:16 in IFA test and up to 1:32 in ELISA. The titer in control group was below 1:4 in both reactions.
parasitology-protozoa ; Toxoplasma gondii ; Sarcocystis suicanis ; immunology ; diagnosis ; immunofluorescence ; enzyme-linked immunosorbent assay

Toxoplasmosis is an opportunistic infection caused by the protozoan parasite Toxoplasma gondii. T. gondii is widespread globally and causes severe diseases in individuals with impaired immune defences as well as congenitally infected infants. The high prevalence rate in some parts of the world such as South America and Africa, coupled with the current drug treatments that trigger hypersensitivity reactions, makes the development of immunotherapeutics intervention a highly important research priority. Immunotherapeutics strategies could either be a vaccine which would confer a pre-emptive immunity to infection, or passive immunization in cases of disease recrudescence or recurrent clinical diseases. As the severity of clinical manifestations is often greater in developing nations, the development of well-tolerated and safe immunotherapeutics becomes not only a scientific pursuit, but a humanitarian enterprise. In the last few years, much progress has been made in vaccine research with new antigens, novel adjuvants, and innovative vaccine delivery such as nanoparticles and antigen encapsulations. A literature search over the past 5 years showed that most experimental studies were focused on DNA vaccination at 52%, followed by protein vaccination which formed 36% of the studies, live attenuated vaccinations at 9%, and heterologous vaccination at 3%; while there were few on passive immunization. Recent progress in studies on vaccination, passive immunization, as well as insights gained from these immunotherapeutics is highlighted in this review.
Drug Discovery/trends ; Global Health ; Humans ; Immunization/*methods ; Immunotherapy/*methods/trends ; Protozoan Vaccines/immunology/isolation & purification ; Toxoplasma/*immunology ; Toxoplasmosis/*therapy

Toxoplasma gondii provokes rapid and sustained nuclear translocation of the signal transducer and activator of transcription 6 (STAT6) in HeLa cells. We observed activation of STAT6 as early as 2 hr after infection with T. gondii by the nuclear translocation of fluorescence expressed from exogenously transfected pDsRed2-STAT6 plasmid and by the detection of phosphotyrosine-STAT6 in Western blot. STAT6 activation occurred only by infection with live tachyzoites but not by co-culture with killed tachyzoites or soluble T. gondii extracts. STAT6 phosphorylation was inhibited by small interfering RNA of STAT6 (siSTAT6). In view of the fact that STAT6 is a central mediator of IL-4 induced gene expression, activation of STAT6 by T. gondii infection resembles that infected host cells has been stimulated by IL-4 treatment. STAT1 was affected to increase the transcription and expression by the treatment of siSTAT6. STAT6 activation was not affected by any excess SOCS's whereas that with IL-4 was inhibited by SOCS-1 and SOCS-3. T. gondii infection induced Eotaxin-3 gene expression which was reduced by IFN-gamma. These results demonstrate that T. gondii exploits host STAT6 to take away various harmful reactions by IFN-gamma. This shows, for the first time, IL-4-like action by T. gondii infection modulates microbicidal action by IFN-gamma in infected cells.
Active Transport, Cell Nucleus ; Animals ; Chemokines, CC/biosynthesis ; Hela Cells ; Humans ; Interleukin-4/*immunology ; Mice ; Mice, Inbred BALB C ; STAT6 Transcription Factor/*immunology/*metabolism ; Toxoplasma/*immunology