Mouse models of chronic toxoplasmosis and atopic dermatitis (AD) were combined to clarify the effect of opportunistic Toxoplasma gondii infection on the development of AD. AD was induced as a chronic contact hypersensitivity (CHS) with repeated challenge of 2,4,6-trinitro-1-chlorobenzene (TNCB) on the dorsal skin of mice. TNCB induced skin thickness increases in both normal and toxoplasmic mice. The changing patterns were different from the sigmoidal which saturated at 20 days in normal mice to the convex saturated at 12 days in toxoplasmic mice with the crossing at 18 days. Compared to normal mice, toxoplasmic mice presented CHS more severely in earlier times and then moderately in later times. These data suggest that host immune modification by T. gondii infection enhances CHS in early times of atopic stimulation but soothes the reaction of CHS in later times in mouse model.
Animals ; Dermatitis, Contact/*immunology/parasitology ; Disease Models, Animal ; Female ; Humans ; Mice ; Mice, Inbred BALB C ; Picryl Chloride/adverse effects ; Skin/immunology/parasitology ; Toxoplasmosis/*immunology/parasitology

Toxoplasmosis, caused by Toxoplasma gondii, is a parasitic zoonosis with worldwide distribution. The present study investigated the prevalence of T. gondii in dogs in Zhanjiang city, southern China, using both serological and molecular detection. A total of 364 serum samples and 432 liver tissue samples were collected from the slaughter house between December 2012 and January 2013 and were examined for T. gondii IgG antibody by ELISA and T. gondii DNA by semi-nested PCR based on B1 gene, respectively. The overall seroprevalence of T. gondii IgG antibody was 51.9%, and T. gondii DNA was detected in 37 of 432 (8.6%) liver tissue samples. These positive DNA samples were analyzed by PCR-RFLP at 3'- and 5'-SAG2. Only 8 samples gave the PCR-RFLP data, and they were all classified as type I, which may suggest that the T. gondii isolates from dogs in Zhanjiang city may represent type I or type I variant. This study revealed the high prevalence of T. gondii infection in dogs in Zhanjiang city, southern China. Integrated measures should be taken to prevent and control toxoplasmosis in dogs in this area for public health concern.
Animals ; Antibodies, Protozoan/blood ; China/epidemiology ; Dog Diseases/epidemiology/*parasitology ; Dogs ; Female ; Genotype ; Liver/parasitology ; Male ; Toxoplasma/classification/genetics/immunology/*isolation & purification ; Toxoplasmosis, Animal/blood/epidemiology/*parasitology

OBJECTIVETo explore the behavioral risk of toxoplasma infection in special population.

METHODSSerum samples from workers in slaughterhouse were collected and tested for the detection of cAg, toxo-IgG, toxo-IgM antibody to toxoplasma, using ELISA. Behavioral measurements were conducted through questionnaire, which was developed according to theory of reasoned action which consists of a measurement model that specifies the relation of measured to behavioral variables and a behavioral variable model to show the influence of behavior variables on each other. Factor analysis methods were used for estimating the parameter of the former and path analyses method for the latter.

RESULTSWith data from 302 research subjects, the responding rate was 95.87%. The overall infection rate was of 19.20% including 15.89% having cAg, 5.63% with toxo-IgG, 2.32% with toxo-IgM, 1.32% with the third of cAg, toxo-IgG and toxo-IgM, 2.65% with the both cAg and toxo-IgG, 1.99% with the both cAg and IgM respectively. There was significant association between toxoplasma infections and contact with dystocia or live pigs, body fluid or harslet. There was no relation between toxoplasma infections and abortion.

RESULTSfrom miscarriage factor analyses showed that except evaluation of behavioral outcomes and behavioral attitudes, internal consistence reliability of others behavioral variables was good (Cronbach's alpha > 0.7). These behavior variables could be explained by their measure items. Path analyses suggested that two components had provided significant independent contributions to those preventive behaviors which significantly correlated to toxoplama infections. Half of the contribution leading to toxoplasma infections had come from behavioral factors. Belief was relatively more important in predicting the preventive behavior than subjective norm.

CONCLUSIONOur findings supported the application of reasoned action theory in understanding the role of behavioral factors in toxoplasma infection.

Abattoirs ; Animals ; Antibodies, Protozoan ; blood ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Male ; Models, Biological ; Occupational Diseases ; blood ; etiology ; parasitology ; Occupational Exposure ; adverse effects ; statistics & numerical data ; Risk Factors ; Toxoplasma ; immunology ; Toxoplasmosis ; parasitology ; transmission ; Toxoplasmosis, Animal ; parasitology ; transmission

In recent years, worldwide surveys of Toxoplasma gondii infection in dogs have been reported. However, only limited surveys of T. gondii infection in police dogs have been available, including China. In the present study, we report the seroprevalence of T. gondii in police dogs in Shenyang, northeastern China. Sera from 291 police dogs were examined for T. gondii antibodies with the modified agglutination test (MAT), and 30.9% animals were tested seropositive. The results of the present study indicated a relatively high prevalence of T. gondii infection in police dogs in Shenyang, China.
Agglutination Tests/veterinary ; Animals ; Antibodies, Protozoan/*blood ; China/epidemiology ; Dog Diseases/*epidemiology/parasitology ; Dogs ; Female ; Male ; Seroepidemiologic Studies ; Toxoplasma/*immunology/isolation & purification ; Toxoplasmosis, Animal/*epidemiology/parasitology

The principal objective of this study was to investigate the prevalence of toxoplasmosis in household and stray cats in Seoul, Republic of Korea. We collected blood samples from 72 stray and 80 household cats, and all samples were examined by ELISA and nested PCR. The overall positive rates of Toxoplasma gondii in stray cats were 38.9% (28/72), with 15.3% (11/72) in ELISA and 30.6% (22/72) in PCR. The positive rate in male stray cats was slightly higher than that of female stray cats. The highest positive rate of T. gondii infection was noted in Gangnam and Songpa populations in ELISA and in Gwangjin population in PCR. In household cats, however, we could not detect any specific antibodies or DNA for T. gondii. In conclusion, we recognized that the infection rate of toxoplasmosis in stray cats in Seoul was considerably high but household cats were free from infection.
Animals ; Animals, Domestic/parasitology ; Antibodies, Protozoan/blood ; Cat Diseases/*epidemiology/immunology/parasitology ; Cats ; Female ; Male ; Prevalence ; Republic of Korea/epidemiology ; Toxoplasma/genetics/immunology/*isolation & purification ; Toxoplasmosis, Animal/*epidemiology/immunology/parasitology

The breeding of domestic rabbits (Oryctolagus cuniculus) for human consumption has a long tradition in China. Infections that can affect the production of meat or even be transmitted from animals to humans are important to monitor, especially for public health reasons as well as for their impact on animal health. Thus, a total of 1,132 domestic rabbit sera from 4 regions in China were collected for serological screening for Encephalitozoon cuniculi and for Toxoplasma gondii by ELISA and modified agglutination test (MAT), respectively. Antibodies to E. cuniculi were detected in 248/1,132 (21.9%) sera tested while antibodies against T. gondii revealed a seroprevalence of 51/1,132 (4.5%). We believe that the present results are of epidemiological implications and public health importance due to the acknowledged susceptibility of humans to E. cuniculi and T. gondii infections. Therefore, routine screening tests of domestic rabbits are proposed considering the zoonotic potential of these parasites.
Animals ; Animals, Domestic/blood/microbiology/parasitology ; Antibodies, Fungal/*blood ; Antibodies, Protozoan/*blood ; China/epidemiology ; Encephalitozoon cuniculi/*immunology/isolation & purification ; Encephalitozoonosis/blood/microbiology/*veterinary ; Female ; Male ; Rabbits/blood/microbiology/parasitology ; Seroepidemiologic Studies ; Toxoplasma/*immunology/isolation & purification ; Toxoplasmosis, Animal/*blood/parasitology

Toxoplasma gondii Korean isolate (KI-1) tachyzoites were inoculated intraduodenally to BALB/c mice using a silicon tube, and the course of infection and immune responses of mice were studied. Whereas control mice, that were infected intraperitoneally, died within day 7 post-infection (PI), the intraduodenally infected mice survived until day 9 PI (infection with 1x10(5) tachyzoites) or day 11 PI (with 1x10(6) tachyzoites). Based on histopathologic (Giemsa stain) and PCR (B1 gene) studies, it was suggested that tachyzoites, after entering the small intestine, invaded into endothelial cells, divided there, and propagated to other organs. PCR appeared to be more sensitive than histopathology to detect infected organs and tissues. The organisms spread over multiple organs by day 6 PI. However, proliferative responses of splenocytes and mesenteric lymph node (MLN) cells in response to con A or Toxoplasma lysate antigen decreased significantly, suggesting immunosuppression. Splenic CD4+ and CD8+ T-lymphocytes showed decreases in number until day 9 PI, whereas IFN-gamma and IL-10 decreased slightly at day 6 PI and returned to normal levels by day 9 PI. No TNF-alpha was detected throughout the experimental period. The results showed that intraduodenal infection with KI-1 tachyzoites was successful but did not elicit significant mucosal immunity in mice and allowed dissemination of T. gondii organisms to systemic organs. The immunosuppression of mice included reduced lymphoproliferative responses to splenocytes and MLN cells to mitogen and low production of cytokines, such as IFN-gamma, TNF-alpha, and IL-10, in response to T. gondii infection.
Animals ; Cell Proliferation ; Cytokines/secretion ; Disease Models, Animal ; Duodenum/immunology/parasitology/pathology ; Endothelial Cells/parasitology ; Histocytochemistry ; Immune Tolerance ; Lymph Nodes/immunology ; Mice ; Mice, Inbred BALB C ; Polymerase Chain Reaction ; Rodent Diseases/immunology/parasitology/pathology ; T-Lymphocyte Subsets/immunology ; Toxoplasma/*immunology/pathogenicity ; Toxoplasmosis, Animal/*immunology/parasitology/pathology

In this experiment, the correlation between antigenemia and specific antibody responses in Toxoplasma gondii-infected rabbits was assessed. We injected 1,000 T. gondii tachyzoites (RH) subcutaneously into 5 rabbits. Parasitemia, circulating antigens, and IgM and IgG antibody titers in blood were tested by ELISA and immunoblot. For detection of parasitemia, mice were injected with blood from rabbits infected with T. gondii and mice died between days 2 and 10 post-infection (PI). Circulating antigens were detected early on day 2 PI, and the titers increased from day 4 PI and peaked on day 12 PI. Anti-Toxoplasma IgM antibody titers increased on day 6 PI and peaked on days 14-16 PI. IgG was detected from day 10 PI, and the titers increased continuously during the experiment. The antigenic protein patterns differed during the infection period, and the number of bands increased with ongoing infection by the immunoblot analysis. These result indicated that Toxoplasma circulating antigens during acute toxoplasmosis are closely related to the presence of parasites in blood. Also, the circulating antigen levels were closely correlated with IgM titers, but not with IgG titers. Therefore, co-detection of circulating antigens with IgM antibodies may improve the reliability of the diagnosis of acute toxoplasmosis.
Animals ; Antibodies, Protozoan/*blood ; Antigens, Protozoan/*blood ; Enzyme-Linked Immunosorbent Assay/methods ; Immunoblotting/methods ; Immunoglobulin G/*blood ; Immunoglobulin M/*blood ; Mice ; Parasitemia ; Rabbits ; Time Factors ; Toxoplasma/*immunology ; Toxoplasmosis, Animal/*immunology/parasitology