scholarly journals The major 85-kD surface antigen of the mammalian form of Trypanosoma cruzi is encoded by a large heterogeneous family of simultaneously expressed genes.

1990 ◽  
Vol 172 (2) ◽  
pp. 589-597 ◽  
Author(s):  
S Kahn ◽  
W C Van Voorhis ◽  
H Eisen
Keyword(s):  
Trypanosoma Cruzi ◽  
Gene Family ◽  
Protozoan Parasite ◽  
Surface Antigens ◽  
African Trypanosomes ◽  
Antigenic Diversity ◽  
Obligate Intracellular ◽  
The Family ◽  
Large Repertoire ◽  
Intracellular Protozoan Parasite

Trypanosoma cruzi is an obligate intracellular protozoan parasite. The parasite mammalian stage surface antigens exhibit extensive antigenic diversity. We have characterized a family of T. cruzi genes that code for a polymorphic set of 85-kD surface antigens, the SA85-1 antigens. The family contains greater than 100 genes and pseudogenes, of which a minimum of nine are transcribed. The gene family is expressed in the mammalian stage only. A subset of the gene family is present in two telomere-linked copies in the genome. Telomere linkage of other expressed SA85-1 genes has not been demonstrated. We have shown that at least three members of the SA85-1 gene family encode antigens at the surface of the mammalian stage of the parasite. Interestingly, these three antigens are expressed on all the trypanosomes examined. This suggests that T. cruzi simultaneously expresses a large repertoire of similar, but diverse antigens at its surface. Thus, T. cruzi exhibits extensive antigenic diversity in a system unique from that of African trypanosomes, perhaps reflecting its intracellular niche.

Temperature, Mitochondria, and Reye's Syndrome

PEDIATRICS ◽  
1983 ◽  
Vol 71 (6) ◽  
pp. 985-985
Author(s):  
RIF S. EL-MALLAKH
Keyword(s):  
Trypanosoma Cruzi ◽  
Chagas Disease ◽  
Protozoan Parasite ◽  
Mitochondrial Enzyme ◽  
Reye's Syndrome ◽  
Electron Microscopic ◽  
Microscopic Studies ◽  
Mitochondrial Defect ◽  
Intracellular Protozoan Parasite

To the Editor.— Mitochondrial failure, manifest by changes in mitochondrial enzyme activity1-3 and morphology,4-5 is central to Reye's syndrome (RS).6 Although it has been variously hypothesized that the mitochondrial changes are secondary to an exogenous toxin,7-12 or an intrinsic mitochondrial defect,6 the actual cause remains obscure. Electron microscopic studies have shown sweelling and loss of cristate in mitochondria of patients with RS. It is interesting that very similar changes occur in Trypanosoma cruzi.13-16 T cruzi is an extracellular/intracellular protozoan parasite which causes Chagas' disease.17

An expanded adenylate kinase gene family in the protozoan parasite Trypanosoma cruzi

2006 ◽  
Vol 1760 (6) ◽  
pp. 913-921 ◽  
Author(s):  
Leon A. Bouvier ◽  
Mariana R. Miranda ◽  
Gaspar E. Canepa ◽  
Maria Júlia M. Alves ◽  
Claudio A. Pereira
Keyword(s):  
Trypanosoma Cruzi ◽  
Gene Family ◽  
Adenylate Kinase ◽  
Protozoan Parasite ◽  
Kinase Gene

scholarly journals Intranasal Vaccinations with the trans-Sialidase Antigen plus CpG Adjuvant Induce Mucosal Immunity Protective against Conjunctival Trypanosoma cruzi Challenges

2010 ◽  
Vol 78 (3) ◽  
pp. 1333-1338 ◽  
Author(s):  
O. K. Giddings ◽  
C. S. Eickhoff ◽  
N. L. Sullivan ◽  
D. F. Hoft
Keyword(s):  
Trypanosoma Cruzi ◽  
Immune Responses ◽  
Body Fluid ◽  
Direct Evidence ◽  
Protozoan Parasite ◽  
Secretory Iga ◽  
Parasite Invasion ◽  
Mucosal Surfaces ◽  
Parasite Replication ◽  
Intracellular Protozoan Parasite

ABSTRACT Trypanosoma cruzi is an intracellular protozoan parasite capable of infecting through mucosal surfaces. Our laboratory has previously elucidated the anatomical routes of infection after both conjunctival and gastric challenge in mice. We have shown that chronically infected mice develop strong immune responses capable of protecting against subsequent rechallenge with virulent parasites through gastric, conjunctival, and systemic routes of infection. We have also shown that intranasal immunizations with the unique T. cruzi trans-sialidase (TS) antigen protect against gastric and systemic T. cruzi challenge. In the current work we have investigated the ability of purified TS adjuvanted with CpG-containing oligonucleotides to induce immunity against conjunctival T. cruzi challenge. We confirm that intranasal vaccinations with TS plus CpG induce TS-specific T-cell and secretory IgA responses. TS-specific secretory IgA was detectable in the tears of vaccinated mice, the initial body fluid that contacts the parasite during infectious conjunctival exposures. We further show that intranasal vaccinations with TS plus CpG protect against conjunctival T. cruzi challenge, limiting local parasite replication at the site of mucosal invasion and systemic parasite dissemination. We also provide the first direct evidence that mucosal antibodies induced by intranasal TS vaccination can inhibit parasite invasion.

scholarly journals Investigation of Toxoplasma gondii Infection in Aborted Fetuses of Sheep Using PCR: A Study in North Khorasan Province, Iran

2020 ◽  
Vol 2020 ◽  
pp. 1-5
Author(s):  
Mitra Salehi ◽  
Hosein Nezami ◽  
Hamid Reza Niazkar
Keyword(s):  
Toxoplasma Gondii ◽  
Gestational Age ◽  
Protozoan Parasite ◽  
Abortion Rate ◽  
Obligate Intracellular ◽  
Significant Difference ◽  
Pcr Method ◽  
Toxoplasma Gondii Infection ◽  
Intracellular Protozoan Parasite

Toxoplasma gondii is a zoonotic obligate intracellular protozoan parasite that infects warm-blooded animals as well as humans worldwide. The purpose of this study was to delineate the prevalence of Toxoplasma infection in aborted fetuses of sheep in North Khorasan province, Iran. Three hundred and ninety-nine samples of the liver (133 samples), placenta (133 samples), and brain (133 samples) from 133 aborted fetuses of sheep were collected from 2015 to 2017. The ages of aborted fetuses were higher than 120 days’ gestational age in this study. According to the samples, sixteen out of 133 aborted fetuses of sheep were infected with T. gondii. Toxoplasma DNA was found in the placenta (68.75%) and liver (31.25%) samples of infected fetuses using the PCR method. The highest and lowest rates of Toxoplasma infection were observed during 2016 and 2017, respectively. Shirvan and Faruj provinces were recognized as the two most infected districts among others. There was a significant difference between the year and abortion rate in sheep due to infection by the Toxoplasma parasite (P<0.05). Furthermore, no significant difference between the prevalence of T. gondii infection and aborted fetuses was seen (P>0.05) in different areas. According to the present study, T. gondii infection can be one of the causes of fetus abortion of sheep in North Khorasan province, Iran.

scholarly journals In Astrocytes the Accumulation of the Immunity-Related GTPases Irga6 and Irgb6 at the Vacuole ofToxoplasma gondiiIs Dependent on the Parasite Virulence

2013 ◽  
Vol 2013 ◽  
pp. 1-10
Author(s):  
Felix P. Lubitz ◽  
Daniel Degrandi ◽  
Klaus Pfeffer ◽  
Anne K. Mausberg
Keyword(s):  
Protozoan Parasite ◽  
Obligate Intracellular ◽  
Virulent Strains ◽  
Resistance System ◽  
A Cell ◽  
The Central Nervous System ◽  
Low Levels ◽  
The Individual ◽  
Common Infection ◽  
Intracellular Protozoan Parasite

Toxoplasma gondiiis an obligate intracellular protozoan parasite responsible for a common infection of the central nervous system. Interferon (IFN)γis the key cytokine of host defence againstT. gondii. However,T. gondiistrains differ in virulence andT. gondiifactors determining virulence are still poorly understood. In astrocytes IFNγprimarily induces immunity-related GTPases (IRGs), providing a cell-autonomous resistance system. Here, we demonstrate that astrocytes prestimulated with IFNγinhibit the proliferation of various avirulent, but not virulent,T. gondiistrains. The two analyzed immunity-related GTPases Irga6 and Irgb6 accumulate at the PV only of avirulentT. gondiistrains, whereas in virulent strains this accumulation is only detectable at very low levels. Both IRG proteins could temporarily be found at the same PV, but did only partially colocalize. Coinfection of avirulent and virulent parasites confirmed that the accumulation of the two analyzed IRGs was a characteristic of the individual PV and not determined by the presence of other strains ofT. gondiiin the same host cell. Thus, in astrocytes the accumulation of Irga6 and Irgb6 significantly differs between avirulent and virulentT. gondiistrains correlating with the toxoplasmacidal properties suggesting a role for this process in parasite virulence.

Seroprevalance of Canine Brucellosis and Toxoplasmosis in Female and Male Dogs and Relationship to Various Factors as Parity, Abortion and Pyometra

2017 ◽  
Author(s):  
Osman Ergene ◽  
Bekir Celebi ◽  
Ibrahim Kucukaslan
Keyword(s):  
Toxoplasma Gondii ◽  
Reproductive Tract ◽  
Protozoan Parasite ◽  
Reproductive Parameters ◽  
Obligate Intracellular ◽  
North Cyprus ◽  
Brucella Canis ◽  
Late Abortion ◽  
Canine Brucellosis ◽  
Intracellular Protozoan Parasite

The objective of this study was to determine the seroprevalance of canine brucellosis and toxoplasmosis in female and male dogs and also determine the realtionship to various factors as parity, abortion and pyometra. Brucella canis is a disease of the reproductive tract that may cause late abortion, infertility and fail of conception with optimum insemination time in females and infection of the sexual organs in males. Toxoplasma gondii is an important obligate intracellular protozoan parasite which can affect all warm-blooded mammals and humans which may cause fatal diseases with severe problems, such as abortion. As a result, in this study B. canis was determined in low seroprevalence in some cases on the island (North Cyprus), T. gondii was determined as an important contagious parasite. Also reproductive parameters like parity, spaying, cyclicity could be important too and it was presented that extended evaluation of these factors is needed with further studies.

scholarly journals Conserved Regions as Markers of Different Patterns of Expression and Distribution of the Mucin-Associated Surface Proteins of Trypanosoma cruzi

2011 ◽  
Vol 80 (1) ◽  
pp. 169-174 ◽  
Author(s):  
Luis M. De Pablos ◽  
Antonio Osuna
Keyword(s):  
Life Cycle ◽  
Trypanosoma Cruzi ◽  
Gene Family ◽  
Signal Peptide ◽  
Fluorescence Intensity ◽  
Surface Proteins ◽  
Content Type ◽  
Conserved Regions ◽  
The Family ◽  
Different Levels

ABSTRACTThe MASP gene family is the second most widely represented gene family in the genome ofTrypanosoma cruzi. One of its main characteristics is that its 5′ and 3′ regions are highly conserved. We assessed the expression of these conserved regions as a marker forT. cruziand also analyzed the expression of themaspgenes and MASP proteins. In parasite strains CL-Brener (DTUVI lineage) and PAN4 (DTUI lineage),maspgenes were expressed at different levels both with regard to the two strains and between stages in the parasite's life cycle. We also studied the expression of the family during the intracellular cycle ofT. cruzi, using antibodies against the conserved MASP signal peptide (SP). Fluorescence intensity showed an increase in expression from 24 h onwards, with a peak in intensity at 72 h postinfection. After 24 and 48 h, the MASP proteins were expressed in 33.33% and 57.14% of the amastigotes, respectively. Our data show that not only the extracellular forms ofT. cruzibut also the intracellular phases express this type of protein, though to different extents in the various forms of the parasite.

scholarly journals Transcriptome analysis of alternative splicing in the pathogen life cycle in human foreskin fibroblasts infected with Trypanosoma cruzi

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Hyeim Jung ◽  
Seonggyun Han ◽  
Younghee Lee
Keyword(s):  
Life Cycle ◽  
Alternative Splicing ◽  
Trypanosoma Cruzi ◽  
Exon Skipping ◽  
Protozoan Parasite ◽  
Rna Seq ◽  
Parasite Life Cycle ◽  
Human Foreskin Fibroblasts ◽  
Insight Into ◽  
Intracellular Protozoan Parasite

Abstract Trypanosoma cruzi is an intracellular protozoan parasite that causes Chagas disease as a zoonotic pathogen. The parasite has been shown to remodel expression in the host transcriptome under different conditions. Although alternative splicing (AS) is involved in virtually every biological function in eukaryotes, including cellular differentiation and responses to immune reactions, host AS events that occur as a result of T. cruzi infection have yet to be explored. In this study, we bioinformatically investigated the transcriptome AS dynamics of T. cruzi (Y strain) infected human foreskin fibroblasts using RNA-Seq data captured over four timepoints (4, 24, 48, and 72 h post infection (hpi)). We identified 1768, 399, 250, and 299 differentially expressed exons (AS exons) at 4, 24, 48, and 72 hpi, respectively, showing that host AS mechanism may have a significant role in the intracellular life cycle of the parasite. We present an exon skipping event in HDAC7, which is a candidate gene that is important in the parasite’s cell cycle. To sum up, this bioinformatics analysis of transcriptome may provide new potential insight into AS regulation in human foreskin fibroblast (HFF) cells infected by T. cruzi and into its implication to the parasite life cycle. Moreover, identified AS genes may provide new potential molecular candidates for improving treatment.

ROLES OF IFN-γ ON STAGE CONVERSION OF AN OBLIGATE INTRACELLULAR PROTOZOAN PARASITE, Toxoplasma Gondii

2002 ◽  
Vol 21 (4-5) ◽  
pp. 405-421 ◽  
Author(s):  
AKIHIKO YANO ◽  
HYE-SEONG MUN ◽  
MEI CHIN ◽  
KAZUMI NOROSE ◽  
KAZUYUKI HATA ◽  
...  
Keyword(s):  
Toxoplasma Gondii ◽  
Protozoan Parasite ◽  
Obligate Intracellular ◽  
Stage Conversion ◽  
Ifn Γ ◽  
Intracellular Protozoan Parasite

scholarly journals Babesia divergens: A Drive to Survive

Pathogens ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 95 ◽  
Author(s):  
Cheryl A Lobo ◽  
Jeny R Cursino-Santos ◽  
Manpreet Singh ◽  
Marilis Rodriguez
Keyword(s):  
Protozoan Parasite ◽  
Blood Stream ◽  
Survival Strategies ◽  
Optimum Conditions ◽  
Obligate Intracellular ◽  
Diverse Species ◽  
Babesia Divergens ◽  
Host Blood ◽  
Intracellular Protozoan Parasite

Babesia divergens is an obligate intracellular protozoan parasite that causes zoonotic disease. Central to its pathogenesis is the ability of the parasite to invade host red blood cells of diverse species, and, once in the host blood stream, to manipulate the composition of its population to allow it to endure unfavorable conditions. Here we will review key in vitro studies relating to the survival strategies that B. divergens adopts during its intraerythrocytic development to persist and how proliferation is restored in the parasite population once optimum conditions return.

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