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Bovine trichomonosis (BT), a disease of the bovine urogenital tract, is caused by the protozoan Tritrichomonas foetus (Tf). Tf causes endometritis, infertility, and premature death of the embryo, which generates considerable economic losses. The proteins released can mediate fundamental interactions between the pathogen and the host, triggering factors associated with the symptomatology, immune evasion and pathogenesis characteristic of the species. However, little is known about the profile of the proteins released by Tf. In order to contribute to their knowledge, we performed an isolation protocol and a proteomic profiling of the supernatant (SN) content of six Tf isolates. A total of 662 proteins present in the SN of Tf were detected, out of which 121 were shared by the six isolates, while the remaining 541 were found in at least one of the isolates studied. The comparative analyses using the databases of Tf strain genome K revealed 32.9% of uncharacterized proteins. The bioinformatic analyses showed that the main molecular functions predicted were binding (47.9%) and catalytic activity (38.2%). Additionally, we performed immunodetection assays to evidence the antigenic potential of SN proteins. Interestingly, we observed great ability to detect SN proteins from all six isolates using serum from immunized mice and infected bulls. A complementary mass spectrometry assay allowed us to determine that the proteins that showed the strongest signal intensity in the immunoassays were Grp78 (A0A1J4IZS3) and Ap65 (A0A1J4JSR1). This work represents the first proteomic characterization of Tf SN proteins and their antigenic potential, which might be interesting for the future design of new diagnosis and treatment methods for BT., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Trypanosoma cruzi, the causative agent of Chagas disease, can be transmitted to the offspring of infected women, which constitutes an epidemiologically significant parasite transmission route in nonendemic areas. It is relevant to evaluate differentially expressed factors in T. cruzi-infected pregnant women as potential markers of Chagas congenital transmission., Methods: Circulating levels of 12 cytokines and chemokines were measured by enzyme-linked immunosorbent assay or cytometric bead array in T. cruzi-infected and uninfected pregnant women in their second trimester of pregnancy and control groups of T. cruzi-infected and uninfected nonpregnant women., Results: Trypanosoma cruzi-infected women showed a proinflammatory Th1-biased profile, with increased levels of tumor necrosis factor (TNF)-α, interleukin (IL)-12p70, IL-15, and monokine induced by interferon-gamma (MIG). Uninfected pregnant women presented a biased response towards Th2/Th17/Treg profiles, with increased plasma levels of IL-5, IL-6, IL-1β, IL-17A, and IL-10. Finally, we identified that high parasitemia together with low levels of TNF-α, IL-15, and IL-17, low TNF-α/IL-10 ratio, and high IL-12p70 levels are factors associated with an increased probability of Chagas congenital transmission., Conclusions: Trypanosoma cruzi-infected pregnant women who did not transmit the infection to their babies exhibited a distinct proinflammatory cytokine profile that might serve as a potential predictive marker of congenital transmission., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Trypanosoma cruzi is the protozoan unicellular parasite that causes Chagas disease. It can be transmitted from infected mothers to their babies via the connatal route, thus being able to perpetuate even in the absence of Triatomine insect vectors. Chagas disease was originally endemic in Central and South America, but migration of infected women of childbearing age has spread the T. cruzi congenital infection to non-endemic areas like North America, Europe, Japan, and Australia. Currently, 7 million people are affected by this infection worldwide. This review focuses on the relevance of the T. cruzi parasite levels in different aspects of the congenital T. cruzi infection such as the mother-to-child transmission rate, the maternal and fetal immune response, and its impact on the diagnosis of infected newborns. Improvements in detection of this parasite, with tools that can be easily adapted to be used in remote rural areas, will make the early diagnosis of infected children possible, allowing a prompt trypanocidal treatment and avoiding the current loss of opportunities for the diagnosis of 100% of T. cruzi congenitally infected infants.

Trypanosoma cruzi , the causing agent of Chagas disease, can be transmitted to the offspring of infected pregnant women, thus being an epidemiologically important way of parasite transmission in humans. In addition, the migration of infected women from endemic areas to nonendemic countries may export this parasite infection. The diagnosis of congenital Chagas disease relies on the detection of the parasite because maternal antibodies are passively transferred to infants during pregnancy. The diagnosis of congenital infection can also be confirmed by detection of infant-specific anti- T cruzi antibodies at 10 months after delivery. Because early detection of T cruzi infection in newborns allows an efficient trypanocidal treatment and cure, more sensitive molecular techniques such as DNA amplification are being used for a prompt parasitological diagnosis of children born to seropositive mothers. In this report, we describe a diagnosis case of a child congenitally infected with T cruzi who tested negative for parasite detection both by microscopic observation and DNA amplification at 20 days and 6 months after delivery. However, at 7 months of age, a hemoculture was made from the infant's blood, and the infective parasite was finally isolated and classified as T cruzi discrete typing unit I. In a retrospective study, real-time polymerase chain reaction also allowed detecting the parasite but failed to detect any parasite load in earlier control samples. This case report stresses that even when molecular techniques are negative, a long-term follow-up is necessary for the diagnosis of infants congenitally infected with T cruzi ., Competing Interests: POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose., (Copyright © 2018 by the American Academy of Pediatrics.)

Mitochondria have an important role in energy production, homeostasis and cell death. The opening of the mitochondrial permeability transition pore (mPTP) is considered one of the key events in apoptosis and necrosis, modulated by cyclophilin D (CyPD), a crucial component of this protein complex. In Trypanosoma cruzi , the protozoan parasite that causes Chagas disease, we have previously described that mitochondrial permeability transition occurs after oxidative stress induction in a cyclosporin A-dependent manner, a well-known cyclophilin inhibitor. In the present work, a mitochondrial parasite cyclophilin, named Tc CyP22, which is homolog to the mammalian CyPD was identified. Tc CyP22-overexpressing parasites showed an enhanced loss of mitochondrial membrane potential and loss of cell viability when exposed to a hydrogen peroxide stimulus compared with control parasites. Our results describe for the first time in a protozoan parasite that a mitochondrial cyclophilin is a component of the permeability transition pore and is involved in regulated cell death induced by oxidative stress.

Trypanosoma cruzi, the causing agent of Chagas disease, leads to an activation of the immune system in congenitally infected infants. In this study, we measured a set of cytokines/chemokines and the levels of parasitemia by quantitative PCR in the circulation of neonates born to T. cruzi-infected mothers to evaluate the predictive value of these mediators as biomarkers of congenital transmission. We conducted a retrospective cohort study of 35 infants with congenital T. cruzi infection, of which 15 and 10 infants had been diagnosed by detection of parasites by microscopy in the first and sixth month after delivery, respectively, and the remaining 10 had been diagnosed by the presence of T. cruzi-specific Abs at 10-12 mo old. Uninfected infants born to either T. cruzi-infected or uninfected mothers were also evaluated as controls. The plasma levels of IL-17A, MCP-1, and monokine induced by IFN-γ were increased in infants congenitally infected with T. cruzi, even before they developed detectable parasitemia or seroconversion. Infants diagnosed between 6 and 12 mo old also showed increased levels of IL-6 and IL-17F at 1 mo of age. Conversely, infants who did not develop congenital T. cruzi infection had higher levels of IFN-γ than infected infants born to uninfected mothers. Monokine induced by IFN-γ, MCP-1, and IFN-γ production induced in T. cruzi-infected infants correlated with parasitemia, whereas the plasma levels of IL-17A, IL-17F, and IL-6 were less parasite load dependent. These findings support the existence of a distinct profile of cytokines and chemokines in the circulation of infants born to T. cruzi-infected mothers, which might predict congenital infection., (Copyright © 2016 by The American Association of Immunologists, Inc.)

Chagas congenital infection is an important health problem in endemic and non-endemic areas in which Trypanosoma cruzi-infected women can transmit the parasite to their offspring. In this study, we evaluated the antibody levels against the T. cruzi Shed Acute Phase Antigen (SAPA) in 91 binomial samples of seropositive pregnant women and their infected and non-infected children by ELISA. In 70 children without congenital T. cruzi transmission, the titers of anti-SAPA antibodies were lower than those of their seropositive mothers. In contrast, 90.5% of 21 congenitally infected children, at around 1 month of age, showed higher anti-SAPA antibody levels than their mothers. Subtracting the SAPA-ELISA mother OD value to the SAPA-ELISA child OD allowed efficient detection of most T. cruzi congenitally infected children immediately after birth, when total anti-parasite antibodies transferred during pregnancy are still present in all children born to seropositive women. A positive correlation was observed between parasitemia levels in mothers and infants evaluated by quantitative DNA amplification and anti-SAPA antibody titers by ELISA. As SAPA serology has proved to be very efficient to detect T. cruzi infection in mother-child binomial samples, it could be of extreme help for early diagnosis of newborns, in maternities and hospitals where DNA amplification is not available. This prompt diagnosis may prevent drop out of the long-term follow-up for future diagnosis and may ensure early trypanocidal treatment, which has proved to be efficient to cure infants with congenital Chagas disease., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: According to the Chagas congenital transmission guides, the diagnosis of infants, born to Trypanosoma cruzi infected mothers, relies on the detection of parasites by INP micromethod, and/or the persistence of T. cruzi specific antibody titers at 10-12 months of age., Methodology and Principal Findings: Parasitemia levels were quantified by PCR in T. cruzi-infected children, grouped according to the results of one-year follow-up diagnosis: A) Neonates that were diagnosed in the first month after delivery by microscopic blood examination (INP micromethod) (n = 19) had a median parasitemia of 1,700 Pe/mL (equivalent amounts of parasite DNA per mL); B) Infants that required a second parasitological diagnosis at six months of age (n = 10) showed a median parasitemia of around 20 Pe/mL and 500 Pe/mL at 1 and 6 months old, respectively, and C) babies with undetectable parasitemia by three blood microscopic observations but diagnosed by specific anti - T. cruzi serology at around 1 year old, (n = 22), exhibited a parasitemia of around 5 Pe/mL, 800 Pe/mL and 20 Pe/mL 1, 6 and 12 month after delivery, respectively. T. cruzi parasites were isolated by hemoculture from 19 congenitally infected children, 18 of which were genotypified as DTU TcV, (former lineage TcIId) and only one as TcI., Significance: This report is the first to quantify parasitemia levels in more than 50 children congenitally infected with T. cruzi, at three different diagnostic controls during one-year follow-up after delivery. Our results show that the parasite burden in some children (22 out of 51) is below the detection limit of the INP micromethod. As the current trypanocidal treatment proved to be very effective to cure T. cruzi - infected children, more sensitive parasitological methods should be developed to assure an early T. cruzi congenital diagnosis.

The relationship between parasite burden and vertical transmission of Trypanosoma cruzi was studied in pairs of chronically infected women and their children in a non-endemic area. Parasitemia was quantified by quantitative polymerase chain reaction (qPCR) in the peripheral blood amplifying a nuclear T. cruzi DNA and expressed as equivalent amounts of CL Brener parasites DNA per ml (eP/ml). Similar levels of parasitemia were found in non-transmitting pregnant women and in non-pregnant women: 1.8 ± 0.5 and 1.5 ± 0.7 eP/ml, respectively. In women pregnant with infected children parasitemia was 11.0 ± 2.7 eP/ml (n=20). In 12 of their neonates the infection was detected by microscopic observation of the parasites in peripheral blood in the 1(st) month of age. These children had variable levels of parasitemia (13,000 ± 7000 eP/ml), that were about 600-fold higher than that found in their mothers. To our knowledge, this is the first quantitative evaluation of parasitemia in these three groups of women and in their congenitally infected children. These parasite quantifications could be a basis to plan the control of mother-to-child transmission of T. cruzi., (Copyright © 2012 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.)

Objective: The presence of autoantibodies with adrenergic and cholinergic activity, capable of triggering neurotransmitter receptor-mediated effects, has been associated with pathogenesis in T. cruzi-infected hosts. The goal of this study was to investigate the production of anti-M2 muscarinic receptor autoantibodies (Anti-M2R AAbs) as well as the IFN-γ profile in children at the early stage of Chagas disease, and to examine whether trypanocidal chemotherapy with benzonidazole (BZ) could modify both response patterns., Methods: This study comprised 30 T. cruzi-infected children (mean age: 13.8 years) and 19 uninfected controls (mean age: 12.7 years). Infected patients were treated with BZ and followed-up. Blood samples collected at diagnosis-T0, end of treatment-T1, and six months later-T2 were analysed by ELISA for detection of Anti-M2R AAbs and circulating levels of IFN-γ., Results: At T0, anti-M2R AAbs were demonstrated in 56.7% of T. cruzi-infected patients, whereas uninfected controls were 100% negative. The average age of Anti-M2R AAbs(+) patients was higher than that from negative population. Infected children also displayed significantly stronger serum IFN-γ responses than controls. Upon BZ treatment, a significant linear decreasing trend in Anti-M2R AAb reactivity was recorded throughout the follow-up, with 29.7-88.1% decrease at T2. IFN-γ circulating levels also declined by T2., Conclusion: Anti-M2R AAbs and IFN-γ raise early during chagasic infection in children and are downmodulated by BZ therapy. These findings reinforce the usefulness of early BZ treatment not only to eliminate the parasite but also to reduce potentially pathogenic immune responses.