Schistosoma japonicum: immunolocalization of paramyosin during
 development

This paper describes the localization of paramyosin immunoreactivity in Schistosoma japonicum and represents the first comparative immunolocalization study among schistosome adult, cercariae and lung schistosomula by electron microscopy. A polyclonal antibody was utilized to immunolabel paramyosin or paramyosin-like proteins. Paramyosin was localized within the muscle layer of all 3 developmental stages. Furthermore, paramyosin was localized within granules of the post-acetabular glands of cercariae, and within the tegument matrix and surface of lung schistosomules. Adults and cercariae did not display any detectable paramyosin on the surface or within the tegument. The possible functions of paramyosin within S. japonicum and the relevance of these findings in relation to the reported protective properties of paramyosin as an anti-schistosome vaccine target molecule are discussed.

Download Full-text

Calpains Induce Egg Production Through Mirnas Secretion in Extracellular Vesicles Released From Paired Adult Worms of Schistosoma Japonicum

10.21203/rs.3.rs-783057/v1 ◽

2021 ◽

Author(s):

Takashi Kumagai ◽

Rieko Shimogawara ◽

Koichiro Ichimura ◽

Shiroh Iwanaga

Keyword(s):

Electron Microscopy ◽

Schistosoma Japonicum ◽

Extracellular Vesicles ◽

Egg Production ◽

Developmental Stages ◽

Calpain Inhibitor ◽

Single Female ◽

Female Specific ◽

Male Specific

Abstract Extracellular vesicles (EVs) have been reported to be secreted from Schistosoma japonicum at all developmental stages. However, the reproduction and communication mechanisms between the paired adults through the EVs in dioecious Trematoda have not been reported. In this study, EVs containing many exosome-like vesicles and microvesicles were observed in the supernatants of paired adults cultured in vitro, and abundant selected miRNAs were contained in them. In particular, the female-specific miR-bantam was present only in vesicles and was hardly secreted outside the vesicles. In this study, we found that male-female pairing induced secretion of miR-3479 and miR-bantam in EVs, but not of male-specific miR-61. Furthermore, ingestion of mouse erythrocytes also increased the production of miRNAs in paired adult and single female worms. Vesicles were found in the teguments of females treated with erythrocytes under electron microscopy. After the paired worms were treated with several inhibitors against the secretion of EVs, only calpain inhibitor (calpeptin) significantly reduced the amount of miRNA in EVs. Furthermore, the worms treated with only calpeptin inhibited egg production in vitro. Together, these results indicate that qualitative miRNA production through EVs regulated by calpain plays a role in egg production in S. japonicum.

Download Full-text

Demonstration of the target molecule of a protective IgE antibody in secretory glands of Schistosoma japonicum larvae

International Immunology ◽

10.1093/intimm/6.7.963 ◽

1994 ◽

Vol 6 (7) ◽

pp. 963-971 ◽

Cited By ~ 46

Author(s):

Takeshi Nara ◽

Naoki Matsumoto ◽

Tuenta Janecharut ◽

Hajime Matsuda ◽

Kazuo Yamamoto ◽

...

Keyword(s):

Schistosoma Japonicum ◽

Target Molecule ◽

Ige Antibody ◽

Secretory Glands

Download Full-text

Ultrastructural alterations of intracellular stages and effects on blood forms of Trypanosoma cruzi induced in vivo by 2-amino-5-(1-methyil-5-nitro-2-imidazolyl)-1,3,4 - Thiadiazole

Revista da Sociedade Brasileira de Medicina Tropical ◽

10.1590/s0037-86821984000200008 ◽

1984 ◽

Vol 17 (2) ◽

pp. 89-93 ◽

Cited By ~ 2

Author(s):

Thaisa de Almeida Maria ◽

Leny de Sousa Filardi ◽

Zigman Brener

Keyword(s):

Electron Microscopy ◽

Single Dose ◽

Trypanosoma Cruzi ◽

Drug Administration ◽

Active Drug ◽

Developmental Stages ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Ultrastructural Alterations

An electron microscopy study shows that the administration of a single dose (500 mg/kg, p.o.) of 2-amino-5-(1-methyl-5-nitro-2-imidazolyl)-1, 3, 4-thiadiazole induces in mice infected with Trypanosoma cruzi results in degenerative lesions of the intracellular stages. Ultrastructural alterations are detected as early as 6 hours after the drug administration and destruction of the parasites occurs within 18 - 36 hours. Trypomastigotes are cleared from the bloodstream 4 to 6 hours after treatment. The combined effect on both developmental stages is apparently responsible for the in vivo ejfects of this drug which is the most active drug ever tested in our laboratory in experimental Chagas' disease.

Download Full-text

Hypothyroidism alters mitochondrial morphology and induces release of apoptogenic proteins during rat cerebellar development

Journal of Endocrinology ◽

10.1677/joe.0.1760321 ◽

2003 ◽

Vol 176 (3) ◽

pp. 321-329 ◽

Cited By ~ 23

Author(s):

R Singh ◽

G Upadhyay ◽

MM Godbole

Keyword(s):

Electron Microscopy ◽

Structural Analysis ◽

Developmental Stages ◽

Cerebellar Development ◽

Mitochondrial Morphology ◽

Mitochondrial Structure ◽

Proteolytic Cascade ◽

Early Developmental Stages ◽

Apoptosis Inducing Factor ◽

Early Developmental

Thyroid hormone (TH) deficiency leads to extensive apoptosis during cerebellar development, but the mechanism still remains unclear. Different signals also converge on mitochondria during apoptosis to induce the release of apoptogenic proteins that activate proteolytic cascade through specific enzymes called caspases. Here we studied the effect of hypothyroidism on alterations in mitochondrial structure and translocation of apoptogenic molecules during rat cerebellar development. Structural analysis of mitochondria was studied by electron microscopy. The translocation of apoptogenic molecules was analyzed by Western blotting. TH deficiency led to vacuolization, enlargement and decrease in the number of cristae. The majority of the proapoptotic molecule, Bax, was localized in mitochondria under hypothyroid conditions whereas a limited presence of Bax was detected in the euthyroid state. Translocation of cytochrome c, apoptosis-inducing factor (AIF) and second mitochondrial-derived activator of caspases (SMAC) from mitochondria to cytosol was detected primarily in early developmental stages in the hypothyroid condition. These experimental results demonstrate that TH maintains mitochondrial architecture and inhibits the release of apoptogenic molecules to prevent excess apoptosis during cerebellar development.

Download Full-text

An Analysis of Aureobasidium Pullulans Developmental Stages by Means of Scanning Electron Microscopy

Mycologia ◽

10.1080/00275514.1977.12020123 ◽

1977 ◽

Vol 69 (4) ◽

pp. 783-792 ◽

Cited By ~ 14

Author(s):

David G. Pechak ◽

Richard E. Crang

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Aureobasidium Pullulans ◽

Developmental Stages ◽

Scanning Electron

Download Full-text

Gene Expression in Developmental Stages of Schistosoma japonicum Provides Further Insight into the Importance of the Schistosome Insulin-Like Peptide

International Journal of Molecular Sciences ◽

10.3390/ijms20071565 ◽

2019 ◽

Vol 20 (7) ◽

pp. 1565 ◽

Cited By ~ 3

Author(s):

Xiaofeng Du ◽

Malcolm Jones ◽

Sujeevi Nawaratna ◽

Shiwanthi Ranasinghe ◽

Chunrong Xiong ◽

...

Keyword(s):

Schistosoma Japonicum ◽

Developmental Stages ◽

Insulin Receptors ◽

Glucose Consumption ◽

Adenosine Diphosphate ◽

Internal Cell ◽

Parasite Survival ◽

Survival And Growth ◽

Insight Into

We showed previously that the Schistosoma japonicum insulin-like peptide (SjILP) binds the worm insulin receptors, thereby, activating the parasite’s insulin pathway and emphasizing its important role in regulating uptake of glucose, a nutrient essential for parasite survival. Here we show that SjILP is differentially expressed in the schistosome life cycle and is especially highly transcribed in eggs, miracidia, and adult female worms. RNA inference was employed to knockdown SjILP in adults in vitro, with suppression confirmed by significantly reduced protein production, declined adenosine diphosphate levels, and reduction in glucose consumption. Immunolocalization showed that SjILP is located to lateral gland cells of mature intra-ovular miracidia in the schistosome egg, and is distributed on the ciliated epithelium and internal cell masses of newly transformed miracidia. In schistosomula, SjILP is present on the tegument in two antero-lateral points, indicating highly polarized expression during cercarial transformation. Analysis of serum from S. japonicum-infected mice by ELISA using a recombinant form of SjILP as an antigen revealed IgG immunoreactivity to this molecule at 7 weeks post-infection indicating it is likely secreted from mature eggs into the host circulation. These findings provide further insights on ILP function in schistosomes and its essential roles in parasite survival and growth in different development stages.

Download Full-text

Toxoplasma modifies macrophage phagosomes by secretion of a vesicular network rich in surface proteins.

The Journal of Cell Biology ◽

10.1083/jcb.103.3.867 ◽

1986 ◽

Vol 103 (3) ◽

pp. 867-874 ◽

Cited By ~ 89

Author(s):

L D Sibley ◽

J L Krahenbuhl ◽

G M Adams ◽

E Weidner

Keyword(s):

Electron Microscopy ◽

Cell Surface ◽

Polyclonal Antibody ◽

Calcium Binding ◽

Structural Modification ◽

Surface Proteins ◽

Structural Proteins ◽

Toxoplasma Infection ◽

Sds Page ◽

Structural Matrix

Modification of macrophage phagosomes begins shortly after formation as Toxoplasma cells secrete membranous vesicles that form a reticulate network within the vacuole. The Toxoplasma-modified compartments then resist normal endocytic processing and digestion. We have used the pronounced Ca++-dependent stability of the intraphagosomal membrane (IPM) network to purify and characterize the structural proteins of this assembly. In addition to the structural matrix, Toxoplasma secretes a discrete set of soluble proteins, including a newly described 22-kD calcium-binding protein. The IPM network adheres to intact Toxoplasma cells after host cell lysis in the presence of 1 mM Ca++; however, the network readily disperses in calcium-free buffer and was purified as vesicles that sedimented at 100,000 g. Purified IPM vesicles were specifically recognized by immune sera from mice with chronic Toxoplasma infection and consisted primarily of a 30-kD protein when analyzed by SDS PAGE. IPM network proteins share a major antigenic component located on the surface of extracellular Toxoplasma cells as shown by immunoperoxidase electron microscopy using a polyclonal antibody prepared against the IPM vesicles. Moreover, in Toxoplasma-infected macrophages, anti-IMP antibody confirmed that the extensive IPM array contains proteins also found on the Toxoplasma cell surface. Our results indicate the IMP network represents a unique structural modification of the phagosome comprised in part of Toxoplasma surface proteins.

Download Full-text