Advances in the axenic isolation methods of Blastocystis sp. and their applications.

Blastocystis sp. is a prevalent protistan parasite found globally in the gastrointestinal tract of humans and various animals. This review aims to elucidate the advancements in research on axenic isolation techniques for Blastocystis sp. and their diverse applications. Axenic isolation, involving the culture and isolation of Blastocystis sp. free from any other organisms, necessitates the application of specific media and a series of axenic treatment methods. These methods encompass antibiotic treatment, monoclonal culture, differential centrifugation, density gradient separation, micromanipulation and the combined use of culture media. Critical factors influencing axenic isolation effectiveness include medium composition, culture temperature, medium characteristics, antibiotic type and dosage and the subtype (ST) of Blastocystis sp. Applications of axenic isolation encompass exploring pathogenicity, karyotype and ST analysis, immunoassay, characterization of surface chemical structure and lipid composition and understanding drug treatment effects. This review serves as a valuable reference for clinicians and scientists in selecting appropriate axenic isolation methods.

Molecular prevalence and subtypes distribution of Blastocystis sp. among outpatients and inpatients in north and south areas of Henan Province, China.

Blastocystis sp. is one of the most common intestinal parasites in humans and many animals. To further understand the infection of Blastocystis hominis (B. hominis) and the distribution of its genotype in some areas of Henan Province, China, 793 stool samples from outpatients and inpatients in Xinxiang City and Xinyang City, Henan Province were collected from April 2020 to July 2022. The samples were detected by polymerase chain reaction and analyzed by univariate analysis and logistic regression analysis. The results showed that the infection rates of B. hominis in Xinxiang and Xinyang were 10.97% (51/465) and 10.98% (36/328), respectively. Although there were no significant differences in B. hominis infection between gender, age, residence, and disease background, the incidence of hematochezia significantly differed from the incidence of abdominal pain, diarrhea, and constipation among participants (χ2  = 15.795, p = 0.002). A total of 87 positive samples were sequenced and compared with Basic Local Alignment Search Tool, and five subtypes (ST1, ST3, ST4, ST6, and ST7) were identified, of which ST3 was the dominant subtype (63.22%, 55/87), followed by ST7 (17.24%, 15/87) and ST1 (16.09%, 14/87). This is the first study that analyzed the prevalence and subtype distribution of B. hominis in southern and northern Henan Province, thus providing new insights into the epidemiology of B. hominis.

Construction a novel detection method for Trichomonas vaginalis based on recombinant enzyme polymerase amplification targeting the Actin gene.

Trichomoniasis is a common and curable sexually transmitted disease worldwide. The rapid, convenient, and accurate diagnosis of trichomoniasis is an important link in the prevention and treatment of the disease. The current detection methods of Trichomonas vaginalis are mainly wet mount microscopy, culture, nested PCR, and loop-mediated isothermal amplification. However, these detection methods have some shortcomings. In this study, a recombinant enzyme polymerase amplification (RPA) assay had been conducted to detect T. vaginalis. The target gene and the corresponding primers were screened, and the reaction system and conditions were optimized in the assay of RPA. The sensitivity and specificity of this detection method were analyzed. The detection efficiency of wet mount microscopy, culture, nested PCR, and RPA was compared by testing 53 clinical samples from vaginal secretions. By screening, the actin gene of T. vaginalis could be used as a target gene for RPA detection of T. vaginalis, and the optimum reaction condition to amplify the actin gene by RPA was at 39°C for 30 min. The detection limit of T. vaginalis DNA using RPA was 1 pg, corresponding to a sensitivity of approximately five trophozoites. The RPA assay demonstrated high specificity for T. vaginalis, and there was no cross-reactivity with Giardia lamblia, Escherichia coli, Lactobacillus, Toxoplasma gondii, Staphylococcus aureus, and Candida albicans. Of the 53 clinical samples, the positive rates of T. vaginalis detected by wet mount microscopy, culture, nested PCR and RPA were 50.9 4% (27/53), 71.7% (38/53), 71.7% (38/53), and 69.81% (37/53), respectively. Compared with culture which was used as the gold standard for diagnosing trichomoniasis, testing clinical samples by wet mount microscopy showed 71.05% sensitivity, 100% specificity, and moderate diagnostic agreement with the culture (K = 0.581, Z = 4.661, p < 0.001). The nested PCR showed 100% sensitivity, 100% specificity, and excellent diagnostic agreement (K = 1, Z = 7.28, p < 0.001), while RPA displayed 97.37% sensitivity, 100% specificity, and excellent diagnostic agreement (K = 0.954, Z = 6.956, p < 0.001). At the present study, rapid amplification of actin gene by RPA could be used as a tool for detection of T. vaginalis. The detection method of RPA was more sensitive than wet mount microscopy and displayed excellent specificity. Moreover, RPA amplification of actin gene did not require a PCR instrument and the amplification time was shorter than that of ordinary PCR. Therefore, the RPA assay was proposed in this study as a point-of-care examination and a diagnostic method of T. vaginalis infection, which exhibited the potential value in the treatment and prevention of trichomoniasis.

Development and application of recombinase polymerase amplification assay for rapid detection of Blastocystis sp.

Blastocystis sp. is a common parasite in the intestinal tract of humans and animals. The clinical diagnosis of Blastocystis sp. mainly depends on the microscopic observation of parasite, which can lead to false-negative results. An accurate and convenient diagnostic approach for Blastocystis sp. infection is crucial for effectively preventing and controlling blastocystosis. Herein, we developed a recombinase polymerase amplification (RPA) method for detecting Blastocystis sp. The results showed that the DNA amplification by RPA established in this study could be performed within 5 min at 37°C, with maximum band intensity observed at 30 min. The minimum detection limit of RPA was 100 fg µL−1, consistent with conventional polymerase chain reaction (cPCR). Furthermore, the RPA method exhibited no cross-reactivity with 7 other non-target pathogens in the intestinal tract. Next, the newly established RPA method was used to analyse 40 fecal samples collected clinically, and the detection results were consistent with cPCR. These results corroborate that the newly developed RPA method has good sensitivity and specificity and offers the advantage of short detection times, which can be harnessed for differential diagnosis and rapid detection of Blastocystis sp.

Association between the infections of Trichomonas vaginalis and uterine cervical human papillomavirus: a meta-analysis.

Trichomonas vaginalis (TV) may have an impact on other reproductive tract infections. Studies on the connection between the infection of TV and human papillomavirus (HPV) have been inconsistent. We performed a systematic review of the relevant articles through keywords that satisfy the criteria and filtered the articles according to the inclusion and exclusion criteria. A total of 16 eligible studies were screened for the meta-analysis, involving a total of 150,605 women. RevMan 5.4 software was used for meta-analysis of the selected literatures. The results showed that the papers included in this study had good homogeneity and no significant publication bias was found in the current analysis. The pooled estimates using a fixed-effects model showed that TV was more prevalent in HPV-infected women than in non-infected women [odds ratio (OR): 1.51, 95% confidence interval (CI): 1.29-1.75]; In turn, HPV was more widespread in TV-infected women than in uninfected women (OR: 3.62, 95% CI: 2.71-4.85). Moreover, the interaction between TV and HPV infection was insensitive to the deletion of some studies and correlation coefficients, consequently, the results were robust and reliable. These results suggested that TV is positively associated with HPV infection, and HPV is also a risk factor for TV infection.

Three-Component Synthesis of Isoquinolone Derivatives via Rh(III)-Catalyzed C-H Activation and Tandem Annulation.

A one-pot three-component synthesis of multifunctionalized isoquinolones from 2-oxazolines, iodonium ylides, and carboxylic acids via Rh(III)-catalyzed oxazolinyl-directed C-H activation and tandem annulation under redox-neutral conditions has been developed. This catalytic system is characterized by readily available starting materials, a wide tolerance of functional groups, a short reaction time, and high yields. The synthetic utility of the cascade reaction was further demonstrated by a gram-scale synthesis and derivatization of the obtained products.

Rhodium(III)-catalyzed oxidative annulation of isoquinolones with allyl alcohols: synthesis of isoindolo[2,1-b]isoquinolin-5(7H)-ones.

An efficient rhodium(III)-catalyzed direct C-H oxidative annulation of isoquinolones with allyl alcohols as C1 synthons has been successfully developed. This protocol enables the straightforward synthesis of structurally diverse isoindolo[2,1-b]isoquinolin-5(7H)-ones with high atom economy, tolerates a broad spectrum of functionalities, and is applicable to one-pot operation from readily available N-methoxybenzamides.

Correction: Rhodium(iii)-catalyzed oxidative alkylation of N-aryl-7-azaindoles with cyclopropanols.

Correction for 'Rhodium(iii)-catalyzed oxidative alkylation of N-aryl-7-azaindoles with cyclopropanols' by Jidan Liu et al., Org. Biomol. Chem., 2021, DOI: .

Rhodium(III)-catalyzed oxidative alkylation of N-aryl-7-azaindoles with cyclopropanols.

An efficient Rh(iii)-catalyzed C-H oxidative alkylation of N-aryl-7-azaindoles with cyclopropanols by merging tandem C-H and C-C cleavage was developed. This transformation features mild reaction conditions, high regioselectivity, and excellent functional group compatibility. The resulting ß-aryl ketone derivatives can be readily transformed into 7-azaindole-containing π-extended polycyclic heteroarenes.

Evaluation of protective efficacy of recombinant Toxoplasma gondii DDX39 protein vaccine against acute and chronic T. gondii infection in mice.

Toxoplasma gondii, a pervasive parasite responsible for toxoplasmosis, poses significant health risks to humans and animals. In this study, we investigated the immunogenicity and protective efficacy of the recombinant T. gondii DDX39 protein formulated with ISA201 adjuvant (rTgDDX39) as a candidate vaccine against toxoplasmosis. The full-length of TgDDX39 gene was successfully amplified, cloned into the pET-30a vector, and expressed in BL21 (DE3) competent cells, which was purified and identified as a 57.1 kDa protein via sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Western blot analysis confirmed that rTgDDX39 was specifically recognized by serum from T. gondii-infected mice. Furthermore, immunization of rats with rTgDDX39 generated antiserum that could specifically recognize the native TgDDX39 protein in T. gondii tachyzoite lysates. Immunofluorescence assay revealed that TgDDX39 was primarily located in the nucleus and perinuclear region of tachyzoites. Our vaccination strategy significantly increased T cell proliferation, with CD4+T cells rising by 21.9% and CD8+T cells by 57.8% by the sixth week compared to the adjuvant control group. Additionally, high titers of anti-rTgDDX39 IgG antibodies were detected in vaccinated mice, with a notable induction of IgG1 and IgG2a isotypes, and IgG1/IgG2a > 1 suggests a Th2-biased immune response. Furthermore, in vitro and in vivo assays demonstrated that polyclonal antibodies raised against rTgDDX39 could inhibit the proliferation of T. gondii RH tachyzoites, highlighting the potential of these antibodies to neutralize this parasite effectively. This study provides compelling evidence of the immunogenicity and protective efficacy of rTgDDX39, supporting its potential as a potential candidate vaccine against toxoplasmosis. The protective efficacy of the vaccine was evaluated in mice challenged with acute (RH) and chronic (PRU) strains of T. gondii, showing a survival time extended to 17 days in the acute model, compared to 13.5 and 14 days in the control groups, and a significant 34% reduction in cyst burden in the chronic model. Additionally, the survival rate in the PRU-infected mice increased from 15 to 20% in the control groups to 45% in the vaccinated group. In vitro and in vivo assays demonstrated that polyclonal antibodies raised against rTgDDX39 could inhibit the proliferation of T. gondii RH tachyzoites, highlighting the potential of these antibodies to neutralize the parasite effectively. This study provides compelling evidence of the immunogenicity and protective efficacy of rTgDDX39, supporting its potential as a candidate vaccine against toxoplasmosis.

Recombinase polymerase amplification - lateral flow dipstick for rapid and visual detection of Blastocystis spp.

Blastocystis spp. is a ubiquitous protozoon in the intestinal tract of human and many animals. Microscopic examination is the main method of clinical diagnosis for Blastocystis spp., which is prone to false negative. A simple and rapid diagnosis of Blastocystis spp. infection is an important step to prevent and control blastocystosis. Here, a recombinase polymerase amplification-lateral flow dipstick (RPA-LFD) assay was developed for rapid visual detection of Blastocystis spp. DNA amplification could be performed within 18 min at 37°C. The minimum DNA detection limit was 1 pg/µL, and there was no cross-reactivity with 12 other non-target pathogens, which was consistent with the sensitivity of conventional PCR (cPCR). Furthermore, 56 fecal samples from the Third Affiliated Hospital of Xinxiang Medical University were tested using RPA and cPCR methods respectively, and the results were completely consistent. The results show that RPA-LFD method has high accuracy and visual results, which provides a new choice for the differential diagnosis and rapid field detection of Blastocystis spp.

A novel detection method based on MIRA-CRISPR/Cas13a-LFD targeting the repeated DNA sequence of Trichomonas vaginalis.

BACKGROUND: Trichomonas vaginalis is a protozoan parasite, widely recognized as the most prevalent non-viral sexually transmitted infection (STI) globally. This infection is linked to various complications, including pelvic inflammatory disease, adverse pregnancy outcomes, and an increased risk of acquiring HIV. Current molecular detection methods for T. vaginalis are often costly and technically challenging. METHODS: We developed a novel detection method for T. vaginalis using a multi-enzyme isothermal rapid amplification-clustered regularly interspaced short palindromic repeats (MIRA-CRISPR)/Cas13a-lateral flow device (LFD). This assay targets the repeated DNA sequence (GenBank: L23861.1) of T. vaginalis and is performed at a constant temperature of 37 °C for approximately 1 hour. RESULTS: The detection limit of genomic DNA (gDNA) using our protocol was 1 × 10-4 ng/µl. Specificity was confirmed by the absence of cross-reaction with gDNA from various other microorganisms such as Staphylococcus aureus, Lactobacillus taiwanensis, Escherichia coli, Monilia albicans, Giardia lamblia, or Toxoplasma gondii. Among 30 clinical samples tested, the positive rates of T. vaginalis detection were 33.33% (10/30) by wet mount microscopy, 40% (12/30) by nested polymerase chain reaction (PCR), 40% (12/30) by MIRA-CRISPR/Cas13a-LFD, and 40% (12/30) by the culture method. Compared with the culture method, the gold standard for diagnosing trichomoniasis, wet mount microscopy showed a sensitivity of 83.3% and moderate diagnostic agreement (kappa value = 0.87). Both nested PCR and MIRA-CRISPR/Cas13a-LFD exhibited 100% sensitivity and excellent diagnostic agreement (kappa value = 1). CONCLUSIONS: The MIRA-CRISPR/Cas13a-LFD method is a convenient, rapid, stable, and accurate diagnostic tool for detecting T. vaginalis. This method has the potential to enhance the diagnosis and management of vaginitis, offering a significant improvement over existing diagnostic techniques.

Dynamic changes in TIGIT expression on the T-cell surface and TIGIT-mediated T-cell dysfunction in the brains of mice with chronic Toxoplasma gondii infection.

The immunosuppressive receptor TIGIT plays a vital role in the regulation of the immune system's response to pathogens. However, the expression pattern of this receptor in mouse brains during infection with Toxoplasma gondii cysts is not known. Here, we provide evidence of immunological changes and TIGIT expression in infected mouse brains through flow cytometry and QPCR. The obtained results show that TIGIT expression on brain T cells rose considerably after infection. T. gondii infection triggered the conversion of TIGIT+ TCM cells to TIGIT+ TEM cells and reduced their cytotoxicity. During the whole period of T. gondii infection, high intensity and persistent expression of IFN-γ and TNF-α in brain and serum of mice. This study shows that chronic T. gondii infection increases TIGIT expression on brain T cells and affects their immune function.

Trichomonas vaginalis adhesion protein 65 (TvAP65) modulates parasite pathogenicity by interacting with host cell proteins.

Trichomonas vaginalis (T. vaginalis) is a widespread and important sexually transmitted pathogen. Adherence to the surface of the host cell is the precondition forthis parasite's parasitism and pathogenicity. Adhesion protein 65 (TvAP65) plays a key role in the process of adhesion. However, how TvAP65 mediates the adhesion and pathogenicity of T. vaginalis to host cellsis unclear. In this study, we knocked down the expression of TvAP65 in trophozoites by small RNA interference. The number of T. vaginalis trophozoites adhering to VK2/E6E7 cells was decreased significantly, and the inhibition of VK2/E6E7 cells proliferation and VK2/E6E7 cells apoptosis and death induced by T. vaginalis were reduced, after the expression of TvAP65 was knocked down. Animal challenge experiments showed that the pathogenicity of trophozoites was decreased by passive immunization with anti-rTvAP65 PcAbs or blocking the TvAP65 protein. Immunofluorescence analysis showed that TvAP65 could bind to VK2/E6E7 cells. In order to screen the molecules interacting with TvAP65 on the host cells, we successfully constructed the cDNA library of VK2/E6E7 cells, and thirteen protein molecules interacting with TvAP65 were screened by yeast two-hybrid system. The interaction between TvAP65 and BNIP3 was further confirmed by coimmunoprecipitation and colocalization. When both TvAP65 and BNIP3 were knocked down by small RNA interference, the number of T. vaginalis adhering to VK2/E6E7 cells and the inhibition of VK2/E6E7 cells proliferation were significantly lower than those of the group with knockdown of TvAP65 or BNIP3 alone. Therefore, the interaction of TvAP65 and BNIP3 in the pathogenesis of T. vaginalis infecting host cells is not unique and involves other molecules. Our study elucidated that the interaction between TvAP65 and BNIP3 mediated the adhesion and pathogenicity of T. vaginalis to host cells, provided a basis for searching for the drug targets of anti-T. vaginalis, and afforded new ideas for the prevention and treatment of trichomoniasis.

Trichomonas vaginalis excretory secretory proteins reduce semen quality and male fertility.

Trichomonas vaginalis (T. vaginalis) infection is the most common non-viral sexually transmitted disease (STD) in the world. It can cause male reproductive dysfunction and infertility. However, the pathogenic mechanism is not clear. In this study, the excretory secretory proteins of T. vaginalis (TvESPs) were collected, concentrated, and sterilized. After sperm co-cultured with TvESPs, the survival rate and motility of sperms were analyzed by seminal routine examination, and the results showed that the TvESPs could significantly reduce the survival rate and motility of sperms. Fluorescence staining displayed that TvESPs could destroy the integrity of sperm acrosomes. Flow cytometry indicated that TvESPs induced sperm apoptosis. By mouse in vitro fertilization, we confirmed that TvESPs could significantly reduce the fertilization ability of sperms and negatively affect the development of the fertilized ovum. Via semi-quantitative analysis, we found that the apoptosis-related p27, SMAC, p53, BAX, BCL-2, XIAP, and BCL-W molecules were down-regulated in mouse sperm cells after interaction between the sperms and TvESPs, which played an important role in regulating sperm apoptosis. In conclusion, our study showed that T. vaginalis degraded semen quality and negatively affected male fertility by TvESPs. TvESPs may damage sperms by breaking the balance between sperm pro-apoptotic and anti-apoptotic molecules. This study proves that T. vaginalis infection is a risk factor for infertility.

The correlation between Trichomonas vaginalis infection and reproductive system cancer: a systematic review and meta-analysis.

BACKGROUND: Trichomonas vaginalis (T. vaginalis) is a microaerophilic protozoan parasite which is responsible for trichomoniasis, the most common non-viral sexually transmitted infection in the world. The infection greatly damages the reproductive system. However, whether T. vaginalis infection can cause reproductive system cancer remains controversial. METHODS: This study systematically searched PubMed, EMBASE, Ovid and Google scholar, and 144 relevant articles were retrieved and classified into three categories: epidemiological investigations (68), reviews (30) and research articles (46). These three types of articles were verified according to their respective inclusion and exclusion criteria. Stata 16 was used to conduct a meta-analysis on the articles of epidemiological investigations for analysing the correlation between T. vaginalis infection and reproductive system cancer. RESULTS: The result of meta-analysis indicated that the rate of T. vaginalis infection in the cancer group was significantly higher than that in the non-cancer group (OR = 1.87, 95% CI 1.29-2.71, I2 = 52%). Moreover, the cancer rate of the population infected with T. vaginalis was significantly higher than that of the population without T. vaginalis infection (OR = 2.77, 95% CI 2.37-3.25, I2 = 31%). The review articles and most research articles stated that the infection of T. vaginalis could lead to cancer and the pathogenic mechanisms were as follows: T. vaginalis promoting inflammatory response, T. vaginalis infection changing the internal environment around parasitic sites and signal transduction pathway, the metabolites secreted by T. vaginalis inducing carcinogenesis and T. vaginalis increasing other pathogenic microbial infection to promote the occurrence of cancer. CONCLUSIONS: Our study confirmed that there was a correlation between the infection of T. vaginalis and reproductive system cancer, and provided some possible research directions for clarifying the carcinogenic mechanisms caused by T. vaginalis infection.

Recombinant Toxoplasma gondii Calreticulin protein provides partial protection against acute and chronic toxoplasmosis.

Toxoplasma gondii, a highly prevalent apicomplexan pathogen, can cause serious or even fatal toxoplasmosis in both animals and humans. Immunoprophylaxis is considered a promising strategy for controlling this disease. Calreticulin (CRT) is known as a pleiotropic protein, which is critical for calcium storage and phagocytosis of apoptotic cells. Our study examined the protective effects of recombinant T. gondii Calreticulin (rTgCRT) as a recombinant subunit vaccine against the T. gondii challenge in mice. Here, rTgCRT was successfully expressed in vitro using prokaryptic expression system. Polyclonal antibody (pAb) has been prepared by immunizing Sprague Dawley rats with rTgCRT. Western blotting showed that rTgCRT and natural TgCRT protein were recognized by serum of T. gondii infected mice and rTgCRT pAb, respectively. T lymphocyte subsets and antibody response were monitored using flow cytometry and enzyme-linked immunosorbent assay (ELISA). The results showed that ISA 201 rTgCRT could stimulate lymphocyte proliferation and induce high levels of total and subclasses of IgG. After the RH strain challenge, a longer survival period was given by the ISA 201 rTgCRT vaccine compared to the control groups; after infection with the PRU strain, we observed a 100% survival rate and a significant reduction in cysts load and size. In the neutralization test, high concentrations of rat-rTgCRT pAb provided 100% protection, while in the passive immunization trial, only weak protection was observed after RH challenge, indicating that rTgCRT pAb needs further modification to improve its activity in vivo. Taken together, these data confirmed that rTgCRT can trigger strong cellular and humoral immune responses against acute and chronic toxoplasmosis.

The interaction between adhesion protein 33 (TvAP33) and BNIP3 mediates the adhesion and pathogenicity of Trichomonas vaginalis to host cells.

BACKGROUND: Trichomonas vaginalis is a widespread and important sexually transmitted pathogen. Adherence to the surface of the host cell is the precondition for the parasitism and pathogenicity of this parasite. Trichomonas vaginalis adhesion protein 33 (TvAP33) plays a key role in the process of adhesion, but how this protein mediates the adhesion and pathogenicity of T. vaginalis to host cells is unclear. METHODS: The expression of TvAP33 in trophozoites was knocked down by small interfering RNA. VK2/E6E7 cells and mice infected with T. vaginalis were used to evaluate the pathogenicity of T. vaginalis. We constructed a complementary DNA library of VK2/E6E7 cells and screened the protein molecules interacting with TvAP33 by the yeast two-hybrid system. The interaction between TvAP33 and BNIP3 (Bcl-2 interacting protein 3) was analyzed by co-immunoprecipitation and colocalization. RESULTS: Following knockdown of TvAP33 expression, the number of T. vaginalis trophozoites adhering to VK2/E6E7 cells decreased significantly, and the inhibition of VK2/E6E7 cell proliferation and VK2/E6E7 cell apoptosis and death induced by T. vaginalis were reduced. Animal challenge experiments showed that the pathogenicity of trophozoites decreased following passive immunization with TvAP33 antiserum or blocking of the TvAP33 protein. Immunofluorescence analysis revealed that TvAP33 could bind to VK2/E6E7 cells. Eighteen protein molecules interacting with TvAP33 were identified by the yeast two-hybrid system. The interaction between TvAP33 and BNIP3 was further confirmed by co-immunoprecipitation and colocalization. When the expression of both TvAP33 and BNIP3 in trophozoites was knocked down by small RNA interference, the number of T. vaginalis adhering to VK2/E6E7 cells and the inhibition of VK2/E6E7 cell proliferation were significantly lower compared to trophozoites with only knockdown of TvAP33 or only BNIP3. Therefore, the interaction of TvAP33 and BNIP3 in the pathogenesis of T. vaginalis infecting host cells is not unique and involves other molecules. CONCLUSIONS: Our study showed that the interaction between TvAP33 and BNIP3 mediated the adhesion and pathogenicity of T. vaginalis to host cells, providing a basis for searching for drug targets for T. vaginalis as well as new ideas for the prevention and treatment of trichomoniasis.

Prevalence and Genotype of Trichomonas vaginalis among Men in Xinxiang City, Henan Province, China.

Trichomonas vaginalis (T. vaginalis) could cause trichomoniasis through sexual transmission, which was globally distributed. In this study, the prevalence and phylogenetic analyses of T. vaginalis among men in Xinxiang were conducted. From October 2018 to December 2019, a total of 634 male clinical samples were collected, including 254 samples of semen, 43 samples of prostate fluid, and 337 samples of urine. These samples were examined by nested PCR and a total of 32 (5.05%) T. vaginalis-positive samples were detected. Among these samples, the positive rates of T. vaginalis in semen, prostate fluid, and urine were 7.87% (20/254), 4.65% (2/43), and 2.97% (10/337), respectively. Three actin genes were successfully isolated and sequenced from the 32 positive DNA samples, and the analysis of the sequence and phylogenetic tree showed that the three actin gene sequences exhibited 99.7%-100% homology to the published actin gene sequence (EU076580) in NCBI, and the T. vaginalis strains in the three positive samples were identified as genotype E. Our results demonstrate a notable genotype of T. vaginalis in the male population and provide insight into the performance of these genetic markers in the molecular epidemiology of trichomoniasis. However, further studies are needed to research the association between the genotype and the pathogenicity of T. vaginalis.

Vaccination with recombinant Toxoplasma gondii bradyzoite-formation deficient 1 (rTgBFD1) antigen provides partial protective immunity against chronic T. gondii infection.

As an apicomplexan pathogen, Toxoplasma gondii still remains a major threat to public health and requires special attention. In fact, positive attempts to identify more effective antigens to provide protection are important to control toxoplasmosis. Latest scientific advances in T. gondii study hint at the probability of the T. gondii bradyzoite-formation deficient 1 (TgBFD1) as an ideal vaccine candidate, since this molecule plays a critical role in regulating the chronic infection of T. gondii. Thus, BALB/c mouse models of acute and chronic T. gondii infections were used to evaluate the TgBFD1 protection efficacy in this study. Before conducting animal trials, antigen analysis of TgBFD1 was performed using DNAstar software and Western blots. The preliminary results suggested that TgBFD1 should be a potent immunogen. Then, this conclusion is confirmed by ELISA assays. After immunization with rTgBFD1, high levels of specific IgG, IgG1, IgG2a, and cytokines (Interferon γ and interleukin 10) were observed, indicating that TgBFD1 could induce strong protective antibody responses. While TgBFD1-specific IgG antibodies were measurable in vaccinated mice, no protection was observed in the acute T. gondii infection (RH strain) assay. However, a noticeable decrease in brain cysts counts of immunized mice compared with negative controls in the latent T. gondii infection (PRU strain) assay was observed. Taken together, these results indicated that rTgBFD1 had the remarkable ability to elicit both humoral and cellular immune responses and could provide partial protective immunity against chronic T. gondii infection.