Toxoplasma gondii antibodies in cancer patients

Seroprevalence of Toxoplasma gondii infection among patients of a tertiary hospital in Guangzhou, Guangdong province, PR China

PURPOSE

This study aimed to explore the prevalence of Toxoplasma gondii (T. gondii) among patients in Guangzhou city, South China, and to identify susceptible patient populations and analyze the causes of infection differences.

METHODS

From May 2020 to May 2022, a total of 637 sera were collected from patients, and 205 sera were collected from health participants as health control. All sera were examined by colloidal gold kits to detect the positivity of antibodies against T. gondii. And the positivity of antibodies in sera was confirmed with ARCHITECT i2000SR system.

RESULTS

The prevalence of T. gondii infection in patients was 7.06% (45/637), which was lower than the prevalence in health participants 4.88% (10/205). Among patients, 34 (5.34%) were positive only for IgG, 10 (1.57%) were only for IgM, and 1 (0.16%) was positive for both IgG and IgM. There was a significant difference in prevalence between male and female patients, but not among different age groups or diseases groups. The prevalence of T. gondii infection in diseases groups varied. The prevalence was relatively high in patients with the disorders of thyroid gland and the malignant neoplasms of digestive organs, which suggests that caution should be taken to avoid T. gondii infection in these patients. Surprisingly, the prevalence was quite low in diffuse Large B-cell Lymphoma (DLBC) patients. This may be due to the overexpression of TNF-α in tumor tissues of DLBC patients and the higher protein level of TNF-α in sera of DLBC patients.

CONCLUSION

This study provides a systematic exploration of the prevalence of T. gondii infection in patients in a tertiary hospital. Our data contributes to a better understanding of the epidemic investigation of T. gondii among patients in South China, which can help the prevention and treatment of the disease caused by T. gondii infection.

Toxoplasma gondii infection in patients with brain tumors in Southern Iran: a case-control study

Considerable evidence points to a dominant role of inflammation in tumor pathology. The biological response of the immune system can be triggered by Toxoplasma gondii as a common brain-tropic parasite. The aim of this study was to investigate an association between Toxoplasma infection and brain tumors. This case-control study was performed on sera of brain tumor patients (n = 124) and age- and sex-matched control subjects (n = 124) in Southern Iran. Data related to tumor site and type were collected during sample collection. Anti-Toxoplasma IgG was assessed by enzyme-linked immunosorbent assay (ELISA). Seroprevalence anti-Toxoplasma IgG was significantly higher in brain tumor patients 30.6% (38/124) compared with 12.1% (15/124) of the healthy controls (OR 3.211; 95% CI 1.658 to 6.219; p = 0.001). The highest seroprevalence was detected in patients with ependymoma (100%), followed by glioblastoma (83%), pituitary adenoma (47.3%), astrocytoma (27.2%), schwannoma (23%), and meningioma (22.6%). The parasite infection was correlated to brain tumor's location i.e., the patients with frontal lobe and sella region tumors had higher seropositivity compared with others (P < 0.05). The higher prevalence of Toxoplasma infection among patients with brain tumor compared with the control group indicates a probable association between the infection and brain tumors.

Onco-Pathogen Mediated Cancer Progression and Associated Signaling Pathways in Cancer Development

Infection with viruses, bacteria, and parasites are thought to be the underlying cause of about 8-17% of the world's cancer burden, i.e., approximately one in every five malignancies globally is caused by an infectious pathogen. Oncogenesis is thought to be aided by eleven major pathogens. It is crucial to identify microorganisms that potentially act as human carcinogens and to understand how exposure to such pathogens occur as well as the following carcinogenic pathways they induce. Gaining knowledge in this field will give important suggestions for effective pathogen-driven cancer care, control, and, ultimately, prevention. This review will mainly focus on the major onco-pathogens and the types of cancer caused by them. It will also discuss the major pathways which, when altered, lead to the progression of these cancers.

Seroprevalence and Risk Factors of Toxoplasma gondii Infection Among High-Risk Populations in Jiangsu Province, Eastern China

Toxoplasma gondii, an opportunistic protozoan, infects one-third of people worldwide and could lead to serious outcomes in immunodeficient or immunocompromised populations. The present study aimed to investigate the prevalence and risk factors for T. gondii infection among high-risk populations in Jiangsu Province, eastern China. We conducted a cross-sectional survey among 4 categories of populations in 13 prefectures including HIV/AIDS patients, livestock breeding/processing (B/P) staff, pregnant women, and cancer patients. We detected specific immunoglobulin G and M (IgG and IgM) levels for each participant using enzyme-linked immunosorbent assay (ELISA) and asked to complete a questionnaire for each participant that covered sociodemographic information as well as the basic knowledge of attitudes toward and the practices for the prevention of toxoplasmosis. A total of 5231 participants distributed across 13 prefecture-level cities was surveyed, including 2455 males and 2776 females. Total seropositivity rate in each population category was as follows: 9.08% (HIV/AIDS patients), 11.65% (livestock B/P staff), 5.50% (pregnant women), and 12.89% (cancer patients). We detected IgM positivity in HIV/AIDS patients (0.47%, 6/1289), livestock B/P staff (0.08%, 1/1330), and cancer patients (0.46%, 6/1303) but not in pregnant women. Further, we detected IgM+IgG positivity only in cancer patients (0.31%, 4/1303). The seropositivity rate for pregnant women was significantly lower, while cancer patients were significantly higher. Higher educational levels were associated with lower seropositivity rates for T. gondii infection. High seropositivity rates were associated with long period of HIV infection among HIV/AIDS patients, frequent contact with livestock among livestock breeding/processing staff and male older patients among cancer patients, respectively. Analysis of practices across all participants showed that frequent contact with pets in everyday life or using the same cutting board for both raw and cooked foods leads to higher seropositivity rates. Therefore, we obtained the seroprevalence and risk factors of toxoplasmosis among high-risk populations in Jiangsu Province which could provide evidence for the implementation of control measures in the near future.

Latent toxoplasmosis and vitamin D concentration in humans: three observational studies

Numerous recent studies show that vitamin D deficiency potentiates various chronic physical and psychiatric disorders and diseases. It has been shown that a similar range of disorders is also associated with latent infection with Toxoplasma gondii (Nicolle et Manceaux, 1908). For instance, among cancer, diabetes and schizophrenia patients, we find a higher prevalence of both toxoplasmosis and vitamin D deficiency. Theoretically, therefore, vitamin D deficiency could be the missing link between toxoplasmosis and these disorders. We tested this hypothesis by searching for decreased vitamin D levels in the serum of subjects infected with T. gondii (furthermore called Toxoplasma-infected subjects) in two cross-sectional and one case-control study. Results of the first cross-sectional study (N = 72) suggest that Toxoplasma-infected neurasthenic patients have non-significantly lower levels of calcidiol than Toxoplasma-free patients (study A: P = 0.26 in women, P = 0.68 in men). However, two other studies (study B: N = 400; study C: N = 191) showed a non-significantly higher concentration of vitamin D in Toxoplasma-infected subjects than in Toxoplasma-free subjects both in men (study B: P = 0.70, study C: P = 0.55) and in women (study B: P = 0.64, study C: P = 0.12). Taken together, our preliminary results thus do not support the hypothesis that toxoplasmosis could be associated with vitamin D decrease.

Increased risk of Toxoplasma gondii infection in cancer patients: A meta-analysis of current evidence based on case-control study

Toxoplasma gondii (T. gondii) is an intracellular protozoan parasite that often infects warm-blooded animals or causes opportunistic infections if exists a suppressed immunity. This study aims to investigate the seroprevalence of T. gondii and its odds ratio (OR) in patients with cancer in compared with healthy individuals, and to find the possible factors. Related literatures reported the seroprevalence of T. gondii in cancer/tumor patients and controls (health individuals) were retrieved from electronic databases PubMed, EMBASE, Chinese Web of Knowledge and The Cochrane Library from inception until Aug 31 2018. The non-weighted prevalence of T. gondii, pooled estimates of OR and its 95% confidence intervals (CI) were calculated through random-effect model. Between-study heterogeneity was tested with Cochrane Q, and statistic I² was to quantify the results. Funnel plot depiction and Egger's linear regression test were combined to evaluate the potential of publication bias. The literature identified a total of 2216 potential studies; the final 18 studies were incorporated, with 6001 cancer/tumor patients and 6067 controls. Our results demonstrated that, the cancer/tumor patients had an elevated seroprevalence of T. gondii (18.43% vs 8.19%), and an increased risk of T. gondii infection (OR = 3.18, 95% CI: 2.65-3.82) when compared with the controls. Subgroup analyses suggested that publication year, study sample size and diagnostic options are closely associated with the seroprevalence of T. gondii. Overall, our study indicates that there is an increased risk of T. gondii infection in cancer/tumor patients, suggesting a precautionary monitoring of T. gondii and related risk factors in patients with cancer/tumor.

Seroprevalence of Toxoplasma gondii infection in cancer patients: A systematic review and meta-analysis

Toxoplasmosis, caused by Toxoplasma gondii, is a great public health concern in cancer patients, which can induce serious pathological effects. This systematic review and meta-analysis was performed to evaluate the worldwide seroprevalence rate of T. gondii infection among cancer patients. A search was conducted on five electronic databases that reported data on T. gondii seroprevalence in cancer patients. The searching process resulted in the inclusion of 57 studies. The results showed that T. gondii had the pooled prevalence of 30.8% in cancer patients using a random-effect model (95% CI: 26.3-35.6). Cancer patients had a higher overall prevalence of T. gondii infection, compared to those without cancer. Furthermore, the odds ratio of toxoplasmosis in cancer patients was 3.1 times, compared to that of controls (95% CI: 2.5-3.8, P < 0.0001). Toxoplasmosis had a higher prevalence in females (40%) than in males (33%). Furthermore, the age group of upper 40 years had the highest prevalence infection rate (30%). In addition, a significant association was also observed between toxoplasmosis infection and year (P < 0.001), type of cancer (P < 0.001), country (P < 0.001), gender (P < 0.001), age (P = 0.006) and diagnostic method (P < 0.001) in cancer patients. Considering the high prevalence of T. gondii infection in cancer patients and its serious outcomes, the researchers are suggested to carry out further studies to prevent and control toxoplasmosis among this population.

Toxoplasmosis an Overlooked Disease: Seroprevalence in Cancer Patients

Background

Toxoplasmosis is one of the most important cosmopolitan life-threatening diseases in immune-compromised patients. It is caused by an intracellular protozoon: Toxoplasma gondii (T. gondii). The parasite can cause pneumonia, encephalitis or disseminated disease in immune-deficient patients and dangerous congenital anomalies in infants born to mothers infected during early pregnancies. The present study aims to evaluate the prevalence of toxoplasmosis in Egyptian cancer patients and to correlate the prevalence with type of malignancy and the different cancer treatment modalities.

Materials and Methods

Blood samples from 150 cancer patients and 50 control subjects have been examined for presence of anti-toxoplasma antibodies using a lateral flow chromatographic immunoassay.

Results

Among cancer patients included in this study, the prevalence of anti- T.gondii antibodies was 20% for IgG and 4% for IgM, while in the control group it was 8% and 2% in the same order. This difference was statistically significant for IgG (P =0.003) but not for IgM (P = 0.44). Patients with solid organ tumors treated with chemotherapy had the highest prevalence rate of toxoplasmosis (28%). It was also found higher in males (26%) than females (10%) and higher among urban (18%) than rural dwellers (16%).

Conclusion

Cancer patients showed a significantly higher rate of infection with T. gondii than their cross-matched control. For that reason, we recommend the inclusion of a screening test for toxoplasmosis in their routine workup.

Detection of anti-Toxoplasma gondii antibodies in chronic myeloid leukemia and acute myeloid leukemia patients

IN:

Background and Aim: Infection of Toxoplasma gondii is a worldwide distribution. Toxoplasmosis in patients who are immunocompromised by virtue of underlying leukemia disease has received relatively little attention. This study was aimed to evaluate IgG and IgM antibodies of T. gondii and to minimize the role of T. gondii and opportunistic infection complication at the early stage of infection in leukemia patients.

Materials and Methods:

The purpose of this assay was to measure anti-T. gondii IgG and IgM antibodies by enzyme-linked immunosorbent assay (ELISA) technique in leukemia patients.

Results:

IgG antibodies against T. gondii were detected by ELISA in 96 (56.4%) leukemia patients and 72 (42.4%) control group. IgM antibodies were found in 10 patients (5.9%) with leukemia and 3 (1.8%) in the corresponding.

Conclusion:

Our finding indicated that leukemia patients under immunosuppressive condition should not be neglected. Toxoplasmosis in leukemia patients as a main risk factor is considered, meanwhile in some patients, due to possibility of the presence of secondary infection that leads to severe toxoplasmosis.

Seroprevalence and molecular evaluation of toxoplasmosis in children with cancer in Khuzestan province, Southwest of Iran

Toxoplasma gondii is an intracellular parasite with global distribution. Toxoplasmosis in individuals with normal immune system is usually asymptomatic, but in immunocompromised patients may lead to death if not cured. In this study, the prevalence rate of acute and chronic toxoplasmosis in children with cancer was investigated using serological and molecular methods. Blood samples were taken from 372 children with cancer in Shafa hospital in Ahvaz, southwest of Iran. Anti-T. gondii IgG and IgM antibodies were investigated by ELISA. The presence of Toxoplasma in the blood samples was evaluated by Nested PCR. Among 372 children with cancer, 155 (41.7%) were positive for anti-T. gondii IgG antibodies and 24 (6.4%) were positive for anti-T. gondii IgM antibodies, as well. In IgG avidity test, 34 (22%) had antibodies indicating acute phase and 121 (78%) had antibodies indicating chronic phase. The Nested PCR results were showed T. gondii parasite in 34 (100%) patients among 34 IgG antibody-positive patients with acute infection, among 16 IgG antibody-positive patients with chronic infection, 10 patients were indicative of T. gondii and 6 patients were not indicative of T. gondii. A total of 50 cases, 44 (88%) were T. gondii-positive and 6 (12%) were T. gondii-negative in Nested PCR. This study showed high prevalence of toxoplasmosis in children with cancer. Results of serological techniques (ELISA and IgG avidity) had a higher overlap with Nested PCR in identifying T. gondii of seropositive patients.

Toxoplasma gondii Infection in Immunocompromised Patients: A Systematic Review and Meta-Analysis

Toxoplasma gondii has been suggested as an important opportunistic pathogen in immunocompromised patients. We conducted a global meta-analysis to assess the prevalence and odds ratios (ORs) of T. gondii infection in immunocompromised individuals. Electronic databases were reviewed for T. gondii infection in HIV/AIDS patients, cancer patients, and transplant recipients, and meta-analyses were conducted to calculate overall estimated prevalence and ORs using random or fixed-effects models. Totally, 72 eligible studies were included. The estimated pooled prevalence of T. gondii infection in immunocompromised patients and the control was 35.9 and 24.7% (p < 0.001), with an OR of 2.24, i.e., 42.1 and 32.0% for HIV/AIDS patients and the control (p < 0.05), 26.0 and 12.1% for cancer patients and the control (p < 0.001), and 42.1 and 34.5% for transplant recipients and the control (p > 0.05), whose estimated pooled ORs were 1.92 (95% CI, 1.44-2.55), 2.89 (95% CI, 2.36-3.55), and 1.51 (95% CI, 1.16-1.95), respectively. This study is the first to demonstrate that the immunocompromised patients are associated with higher odds of T. gondii infection, and appropriate prevention and control measures are highly recommended for these susceptible populations.

High Toxoplasma gondii Seropositivity among Brain Tumor Patients in Korea

Toxoplasma gondii is an intracellular protozoan that can modulate the environment of the infected host. An unfavorable environment modulated by T. gondii in the brain includes tumor microenvironment. Literature has suggested that T. gondii infection is associated with development of brain tumors. However, in Korea, epidemiological data regarding this correlation have been scarce. In this study, in order to investigate the relationship between T. gondii infection and brain tumor development, we investigated the seroprevalence of T. gondii among 93 confirmed brain tumor patients (various histological types, including meningioma and astrocytoma) in Korea using ELISA. The results revealed that T. gondii seropositivity among brain tumor patients (18.3%) was significantly (P<0.05) higher compared with that of healthy controls (8.6%). The seropositivity of brain tumor patients showed a significant age-tendency, i.e., higher in younger age group, compared with age-matched healthy controls (P<0.05). In conclusion, this study supports the close relationship between T. gondii infection and incidence of brain tumors.

The Seroprevalence of Toxoplasma gondii in Chinese Population With Cancer: A Systematic Review and Meta-analysis

Toxoplasmosis is fatal in the immunocompromised individuals such as cancer patients with chemotherapy. Clinical toxoplasmosis in cancer patients is a great public health concern in China. We performed this meta-analysis to assess the seroprevalence and odds ratios (ORs) of Toxoplasma gondii in Chinese population with cancer compared with those without. A methodical literature search was conducted with the help of the PubMed, Web of Knowledge, Embase, Chinese Web of Knowledge, Wanfang, and Chongqing VIP database. Case-control studies published from their inception until April 2015, reporting the seroprevalence of T. gondii in Chinese population with cancer, were covered as well. The nonweighted prevalence, pooled random-effects estimates of ORs, and 95% confidence intervals (CIs) were all calculated. Nineteen studies including 4493 cases and 6797 controls were incorporated in the meta-analysis. The overall seroprevalence of T. gondii was higher in population with cancer compared with those without ((20.59% vs 6.31%, P < 0.001; OR 3.90, 95% CI 3.00-5.07). The OR of T. gondii in cancer patients is further subgrouped according to publication year, sample size, and diagnostic methods. The pooled OR estimates were 4.80 (95% CI 2.57-8.99) from 1991 to 1999, 4.96 (95% CI 3.03-8.12) during 2000 to 2005, and 2.94 (95% CI 2.46-3.50) during 2006 to 2015. The pooled OR estimates were 6.16 (95% CI 3.87-9.78) when the sample size was below 400, 5.37 (95% CI 3.84-7.53) when the sample size was between 400 and 500, and 2.58 (95% CI 2.17-3.07) when the sample size was above 500. The pooled OR estimates were 5.50 (95% CI 3.98-7.62) by using indirect hemagglutination assay method, and 3.15 (95% CI 2.67-3.72) by using enzyme-linked immunosorbent assay method. The meta-analysis study found Chinese population with cancer had higher seroprevalence rates of T. gondii compared with those without.

Immunodiagnosis and molecular validation of Toxoplasma gondii-recombinant dense granular (GRA) 7 protein for the detection of toxoplasmosis in patients with cancer

Serological assays for the diagnosis of toxoplasmosis mostly rely on the tachyzoite specific antigens of Toxoplasma gondii, which are difficult to produce by conventional methods. The aim of this study was to clone and express of GRA7 protein of T. gondii and evaluate its potential for immunodiagnosis of toxoplasmosis in cancer patients. As well as validate the results using a new molecular assay, LAMP technique. The GRA7 gene was successfully cloned, expressed and purified by affinity chromatography and the production was evaluated by SDS PAGE, dot blot and western blot analyses. The rGRA7 was used for developing an ELISA based on the rGRA7 using sera from patients with toxoplasmosis and healthy controls. Furthermore, 50 serum samples from leukemic children infected with toxoplasmosis and 50 seronegative controls were included to evaluate the sensitivity and specificity of rGRA7 based ELISA. Finally, the LAMP technique was used to assess the accuracy and validity of the results obtained by rGRA7 based ELISA. The consistency of the results of two tests was determined by using the Kappa coefficient of agreement. The rGRA7 showed higher and optimum immunoreactivity with 1:100 dilution of serum from Toxoplasma infected patients. The sensitivity and specificity of test were calculated as 92 and 94%, respectively. According to the Kappa coefficient of agreement, there was a significant conformance between the results obtained by ELISA based on the rGRA7 and the results of LAMP technique (≈96%, P<0.001). Findings of the present study showed that rGRA7 can be used as a potential immunogenic antigen for developing immunodiagnostic tools for immunodiagnosis of toxoplasmosis in patients including patients with cancer.

Seroprevalence and genetic characterization of Toxoplasma gondii in cancer patients in Anhui Province, Eastern China

Background

Recent studies have indicated the predominance of Toxoplasma gondii genotype Chinese 1 in animals in China. However, little is known of the genetic features of the parasite in humans. This study aims to determine the prevalence of anti-T. gondii antibodies based on which the genetic character of the parasite was identified in cancer patients in China.

Methods

A total of 1014 serum samples with malignant neoplasms were collected from six tertiary-care hospitals (HAUCM, APH, HAMU, XAH, FHH and HBMC) from January, 2012 to August, 2013. Antibodies against T. gondii were examined by enzyme-linked immunosorbent assay (ELISA). Blood samples were subsequently used for PCR assay to detect T. gondii DNA (gra6). The DNA positive samples were subjected to genotyping using a multiplex multilocus nested PCR-RFLP at 10 loci, including sag1, sag2, sag3, btub, gra6, l358, c22-8, c29-2, pk1 and apico. Samples from the patients were anonymous and only data with regard to age and gender was available at sample collection.

Results

Overall, 8.38% (85/1014) of the examined patients showed positive antibodies against T. gondii. Among them, 61 (6.02%) were seropositive only for IgG, 16 (1.58%) were only for IgM, and 8 (0.79%) were found to be positive for both IgG and IgM. The seroprevalence of antibodies to Toxoplasma ranged from 5.8% to 11.0%, without regional difference (χ² = 4.764, P = 0.445). No significant differences of the positive rates of T. gondii infection were noted in genders (male, 8.96%; female, 7.45%) (χ² = 0.707, P = 0.400) and in ages (χ² = 1.172, P = 0.947). Of 1014 DNA samples, 36 (3.55%) were positive for T. gondii by nested PCR at gra6 locus and nine gave rise to complete genotyping results. All samples with achieved PCR-RFLP genotyping showed a common genetic character of type Chinese 1 (ToxoDB#9).

Conclusion

Seroprevalence of toxoplasmosis in immunosuppressed individuals is rarely reported in China and we presented a positive rate of 8.38% in cancer patients. Toxoplasma genomic DNA genotyping demonstrated a common genetic character of Chinese 1, indicating a possible pathogenic origin of animals in human infection.

Diphenyl diselenide and sodium selenite associated with chemotherapy in experimental toxoplasmosis: influence on oxidant/antioxidant biomarkers and cytokine modulation

SUMMARY The aim of this study was to assess the effect of sulfamethoxazole/trimethoprim (ST) supplemented with diphenyl diselenide and sodium selenite in experimental toxoplasmosis, on oxidant/antioxidant biomarkers and cytokine levels. Eighty-four BALB/c mice were divided in seven groups: group A (negative control), and groups B to G (infected). Blood and liver samples were collected on days 4 and 20 post infection (p.i.). Levels of thiobarbituric acid (TBA) reactive substances and advanced oxidation protein products (AOPP) were assessed in liver samples. Both biomarkers were significantly increased in infected groups on day 4 p.i., while they were reduced on day 20 p.i., compared with group A. Glutathione reductase (GR) activity significantly (P<0·01) increased on day 4 p.i., in group G, compared with group A. INF-γ was significantly increased (P<0·001) in both periods, day 4 (groups B, C, F and G) and 20 p.i. (groups C, F and G). IL-10 significantly reduced (P<0·001) on day 4 p.i. in group B; however, in the same period, it was increased (P<0·001) in groups C and G, compared with group A. On day 20 p.i., IL-10 increased (P<0·001) in groups F and G. Therefore, our results highlighted that these forms of selenium, associated with the chemotherapy, were able to reduce lipid peroxidation and protein oxidation, providing a beneficial immunological balance between the production of pro- and anti-inflammatory cytokines.

Major emerging and re-emerging zoonoses in China: a matter of global health and socioeconomic development for 1.3 billion

Emerging and re-emerging zoonoses are a significant public health concern and cause considerable socioeconomic problems globally. The emergence of severe acute respiratory syndrome (SARS), highly pathogenic avian influenza (HPAI) H5N1, avian influenza H7N9, and severe fever with thrombocytopenia syndrome (SFTS), and the re-emergence of rabies, brucellosis, and other zoonoses have had a significant effect on the national economy and public health in China, and have affected other countries. Contributing factors that continue to affect emerging and re-emerging zoonoses in China include social and environmental factors and microbial evolution, such as population growth, urbanization, deforestation, livestock production, food safety, climate change, and pathogen mutation. The Chinese government has devised new strategies and has taken measures to deal with the challenges of these diseases, including the issuing of laws and regulations, establishment of disease reporting systems, implementation of special projects for major infectious diseases, interdisciplinary and international cooperation, exotic disease surveillance, and health education. These strategies and measures can serve as models for the surveillance and response to continuing threats from emerging and re-emerging zoonoses in other countries.

A comparative study between excretory/secretory and autoclaved vaccines against RH strain of Toxoplasma gondii in murine models

Toxoplasma gondii is an obligate intracellular protozoan that has a major importance in public health, in addition to veterinary medicine. Therefore, the development of an effective vaccine for controlling toxoplasmosis is an important goal. Excretory/secretory antigens (ESA), were previously identified as potential vaccine candidates, proved to play important roles in the pathogenesis and immune escape of the parasite. In addition, autoclaved Toxoplasma vaccine (ATV) is a special type of killed vaccine, recently characterized. The aim of the present work was, to compare between excretory/secretory and ATV against RH strain of T. gondii in mice based on; parasitological and histopathological levels. Tachyzoites were harvested from peritoneal exudates of infected mice and were used for challenge infection and vaccine preparation. BCG was used as an adjuvant. Mice were allocated equally into five groups; they were vaccinated intradermally over the sternum. The results of this study showed that the survival time after challenge, extended up to 16 days in ESA vaccinated group and up to 15 days in autoclaved Toxoplasma vaccinated group. ESA vaccinated group exhibited a profound decrease in parasite load following parasite challenge with a higher percentage of reduction in parasite count in all examined organs than the autoclaved Toxoplasma vaccinated group. The histopathological picture of the liver in both immunized groups, revealed marked reduction in the pathological changes observed as compared to controls, especially in ESA vaccinated group. It was concluded that vaccination with ESA showed more promising results versus ATV, as demonstrated by the survival rate of vaccinated mice, tachyzoites count and histopathological examination.

Seroprevalence of Toxoplasma gondii in slaughtered horses and donkeys in Liaoning province, northeastern China

Background

Toxoplasma gondii is an important zoonotic pathogen infecting humans and almost all warm-blooded animals. The most common sources of human infection are ingestion of tissue cysts in raw or undercooked meat. However, limited information is available about T. gondii infection in horses and donkeys in China. In the present study, we report the seroprevalence of T. gondii infection in horses and donkeys in Liaoning province, northeastern China.

Methods

Serum samples were collected from 711 and 738 slaughtered horses and donkeys, respectively, in 13 regions of Liaoning province. The modified agglutination test (MAT) was used to test the specific antibodies to T. gondii.

Results

In this study, 178 of 711 (25.0%) horses were seropositive for T. gondii with titers of 1:25 in 81, 1:50 in 62, 1:100 in 33, and 1:200 in 2, and seroprevalence of T. gondii infection from 13 regions ranged from 8.2% to 37.0%. Antibodies to T. gondii were found in 174 of 738 (23.6%) donkeys with titers of 1:25 in 66, 1:50 in 54, 1:100 in 49, and 1:200 in 5, and seroprevalence varied in 13 different regions, ranging from 9.1% to 32.6%.

Conclusions

The results of the present study indicated that the rate of infection with T. gondii in horses and donkeys is a little high in Liaoning province, northeastern China in comparison to other surveys in China, which suggests that consumption of horse and donkey meat in this area may represent a potential source for human infection with T. gondii.

Detection of murine toxoplasmosis using magnetic bead-based serum peptide profiling by MALDI-TOF MS

Establishment of a rapid, highly specific, and accurate method for diagnosis of Toxoplasma gondii infection is essential to control and prevent zoonotic toxoplasmosis. In this study, a novel diagnostic strategy using magnetic bead-based serum peptide profiling by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was developed. The serum peptides (samples I, II, and III) from T. gondii RH strain-infected mice at days 3, 6, and 9 post-infection (p.i.), and healthy mice were enriched by the optimized magnetic bead-based hydrophobic interaction (MB-HIC8). The mass spectrograms were acquired by MALDI-TOF MS, and analyzed by ClinProTools bioinformatics software from Bruker Daltonics. The diagnostic models from T. gondii RH-infected serum peptide profiling of samples I, II, and III were produced by genetic algorithms, and verified by cross-validation. The sample II model could correctly recognize T. gondii RH strain infection in mice at days 3, 6, and 9 p.i. with a sensitivity of 91.1% and a specificity of 96.7%., and also detect T. gondii ME49 strain-infected serum samples at days 3, 6, 9, and 12 p.i. with a sensitivity of 91.7%. The results of the present study suggest that serum peptide profiling by MALDI-TOF MS is a novel potential tool for the clinical diagnosis of acute T. gondii infection.

Detection of IgM and IgG anti-Toxoplasma antibodies in renal transplant recipients using ELFA, ELISA and ISAGA methods: comparison of pre- and post-transplantation status

In the transplant recipient patients receive immunosuppressive therapy, the possibility of reactivation of the old infection or acquisition of infection from a donor's tissue increases. In this study, IgM and IgG anti-Toxoplasma immunoglobulins seroconversion in renal transplant recipients (RTRs) have been evaluated before and after transplantation. This is a prospective cohort study on a total of 102 RTRs. Two serum samples were obtained from each patient. The first was taken before administration of any immunosuppressive drugs such as corticosteroids and the second was taken 3 months after transplantation. The IgM and IgG anti-Toxoplasma antibodies were assayed by enzyme-linked flourescence assay (ELFA) and enzyme-linked immunosorbent assay (ELISA) techniques. IgM/immunosorbent agglutination assay (ISAGA) method has also been used. All RTRs were tested for toxoplasmosis before and after transplantation. ELFA identified 65 (63·7%) pre-transplantation samples as IgG+ and did not detect any positive IgM samples. However, IgM was detected in three (2·9%) post-transplantation samples by this method. Forty-nine (48%) pre-transplantation samples were reported IgG+ by ELISA and no IgM positive sample was identified by this method. ELISA has detected two (1·9%) IgM-positive reactions in post-transplantation samples. By IgM/ISAGA method, we have detected no IgM positive reactions in pre-transplantation samples, whereas 3 months later (second sampling) IgM antibody was detected in 3 (2·9%) cases. Secondary toxoplasmosis infection was observed in 30 cases per 1000 RTRs, which indicates that screening for toxoplasmosis infection should be performed in developed countries for these patients. On the other hand, as the risk of re-active toxoplasmosis infection exists in developing nations, they should consider the necessary preventive measures to control this condition.

Seroprevalence of Toxoplasma gondii infection in slaughtered pigs and cattle in Liaoning Province, northeastern China

Toxoplasmosis is an important food-borne parasitic disease. In the present study, the seroprevalence of Toxoplasma gondii infection in slaughtered pigs and cattle was surveyed in Liaoning Province, northeastern China in May and June 2011. In total, 1,164 porcine serum samples and 646 bovine serum samples were collected from 5 counties and examined for T. gondii antibodies by an indirect hemagglutination test. Antibodies to T. gondii were found in 12.0% (140/1,164) of pigs, with some regional differences. The highest prevalence of 14.4% (47/326) was found in Fuxin followed by 12.5% (62/497) in Jinzhou; overall, 6.0% (39/646) was observed in cattle but with no regional difference (P > 0.05). Prevalence of T. gondii infection in pigs was also significantly higher compared to cattle (P < 0.05). The results of the present study indicate that infection with T. gondii in pigs and cattle is widely spread in China including Liaoning Province, northeastern China, and is, therefore, of public health concern.

Seroprevalence of Toxoplasma gondii infection in female sterility patients in China

Toxoplasmosis is an important parasitic disease worldwide and is related to certain psychiatric disorders and sterility. In the present study, serum samples from 882 female sterility patients and 107 pregnant-puerperant women were assayed for anti- T. gondii IgG antibodies using ELISA. The overall T. gondii seroprevalence was 14.8%. In the female sterility patients, 15.9% (140/882) were seropositive and, in the pregnant-puerperant women, 5.6% (6/107) were positive for anti- T. gondii IgG antibodies. There was a significant difference between the 2 groups ( P < 0.05). The samples were further divided into 5 groups based on age, but no significant difference was found among the 5 groups (P > 0.05). Results of the present study argue for more attention to prevention of T. gondii infection in the female population and, in particular, women of childbearing age.

Seroepidemiology of Toxoplasma gondii infection in patients with vision and hearing impairments, cancer, HIV, or undergoing hemodialysis in Durango, Mexico

Toxoplasma gondii infection may cause a variety of symptoms involving virtually all organs. Little is known of the epidemiology of T. gondii infection in different patient groups in Mexico. We sought to determine the prevalence of T. gondii infection and associated epidemiological characteristics in 472 patients in Durango, Mexico. Participants were tested for T. gondii IgG and IgM antibodies. In addition, sociodemographic, clinical, and behavioral characteristics from each participant were obtained. Seroprevalences of T. gondii IgG antibodies were found in 7 (8.2%) of 85 patients with hearing impairment, 5 (10.0%) of 50 patients with hemodialysis, 28 (12.0%) of 234 patients with visual impairment, and 7 (6.8%) of 103 at risk of immunosuppression. In total, 47 (10%) of 472 subjects had IgG T. gondii antibodies; 6 (1.3%) of them also had IgM anti- T. gondii antibodies. Patients born in Durango State had a significantly lower prevalence of T. gondii infection than patients born in other Mexican states (9.0% vs. 21.4%, respectively; P < 0.05). Multivariate analysis showed that T. gondii infection was significantly associated with consumption of undercooked meat (adjusted odds ratio [OR] = 2.95; 95% confidence interval [CI]: 1.18-7.35) or raw cow's milk (adjusted OR = 2.52; 95% CI: 1.28-4.96), presence of cats at home (adjusted OR = 2.01; 95% CI: 1.06-3.78), raising animals (adjusted OR = 2.44; 95% CI: 1.06-5.63), or eating away from home (adjusted OR = 2.70; 95% CI: 1.03-7.11). In the group of patients with visual impairment, those with reflex impairment had a significantly higher frequency of T. gondii infection than those with normal reflexes (19% vs. 9.4%, respectively: P = 0.04). Results of the present study are the first step in the design of prevention programs to avoid the sequelae of toxoplasmosis.

Seroprevalence of Toxoplasma gondii infection and characteristics of seropositive patients in general hospitals in Daejeon, Korea

To figure out the epidemiological status and relevance with other diseases in toxoplasmosis, we checked serum IgG antibody titers of 1,265 patients and medical records of seropositive patients. Seropositive rates were 6.6% by latex agglutination test (LAT) and 6.7% by ELISA. No significant differences were detected between sexes and age groups. The peak seroprevalence was detected in the 40-49-year-old age group. According to clinical department, Toxoplasma-positive rates were high in patients in psychiatry, ophthalmology, health management, emergency medicine, and thoracic surgery. Major coincidental diseases in seropositive cases were malignant neoplasms, diabetes mellitus, arthritis, chronic hepatitis B, chronic renal diseases, schizophrenia, and acute lymphadenitis, in the order of frequency. In particular, some patients with chronic hepatitis B and malignant neoplasms had high antibody titers. These results revealed that the seroprevalence of toxoplasmosis in a general hospital-based study was similar to that in a community-based study, and T. gondii seropositivity may be associated with neoplasms, diabetes, and other chronic infections.

Anti-Toxoplasma gondii activity of GAS in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

The sarcotesta of Ginkgo biloba is a Chinese herbal medicine used for treating toxoplasmosis, a serious disease requiring treatment with antibiotics that can have serious side effects.

AIM OF THE STUDY

To investigate the anti-Toxoplasmagondii activity of ginkgolic acids (GAs) isolated from the Ginkgo biloba sarcotesta in Toxoplasmagondii-infected human foreskin fibroblast (HFF) cells in vitro.

MATERIALS AND METHODS

The safe concentration of GAs for HFF cells was determined by methyl thiazolyl tetrazolium (MTT) cell proliferation assay. The presence of Toxoplasmagondii was measured by [3H]-thymine deoxyriboside ([3H]-TdR) and [3H]-leucine ([3H]-Leu) incorporation, as well as Giemsa staining. The positive control was the commonly used and highly effective antibiotic azithromycin.

RESULTS

Light microscopy revealed that most HFF cells were infected after 4h of exposure to Toxoplasmagondii. After 48 h of exposure to either GAs or azithromycin, Toxoplasmagondii DNA and protein synthesis were minimal, there were no visible parasites in HFF cells, and the HFF cells had no significant morphological changes.

CONCLUSIONS

These results demonstrate that GAs have significant anti-Toxoplasma activity with low toxicity to HFF cells, suggesting that GAs could be an alternative treatment for toxoplasmosis.