Proteinases in the excretory/secretory products (ES) of adult Trichinella spiralis

SUMMARYAdult Trichinella spiralis were maintained in vitro using defined media and the material excreted/secreted (ES) during this time examined for proteolytic enzyme (proteinase) activity using an azocasein assay and gelatin-substrate gels. Several discrete proteinases in the size range 14–100 kDa were observed with optimal activity at pH 7·5. The use of a class-differentiating panel of proteinase inhibitors indicated that serine proteinases were predominant although some inhibition was evident in the presence of cysteine and metalloproteinase inhibitors. Of a panel of potential natural protein substrates tested, ES proteinases only degraded fibrinogen and plasminogen and degradation was, in part, susceptible to the action of serine, cysteine and aspartyl proteinase inhibitors. In addition, antibody harvested from immune but not normal mice inhibited ES proteinase activity, an observation of relevance to the immunobiology of Trichinosis.

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Differential regulation of spleen cell-mediated eosinophil and neutrophil-macrophage production

Blood ◽

10.1182/blood.v55.3.489.489 ◽

1980 ◽

Vol 55 (3) ◽

pp. 489-493 ◽

Cited By ~ 12

Author(s):

SH Bartelmez ◽

WH Dodge ◽

DA Bass

Keyword(s):

Growth Factor ◽

Contrast Media ◽

Spleen Cell ◽

Trichinella Spiralis ◽

Cell Types ◽

Differential Regulation ◽

Spleen Cells ◽

Secretory Products ◽

Kinetics Of

Abstract Nonadherent spleen cells of mice infected with Trichinella spiralis released growth stimulatory factors (GSFs) in vitro when challenged with excretory/secretory products of muscle stage larvae. The assay of GSF was based on proliferation of normal, nonadherent syngeneic marrow cells in liquid tube cultures. Media conditioned for 1 day by challenged spleen cells stimulated eosinophil production but failed to stimulate production of other cell types. In contrast, media conditioned for 5 days supported eosinophil, neutrophil, and macrophage production. The kinetics of cell production were also different. Eosinophil production started within 1 day, reached a peak at day 2, and was down to control levels by day 4. In contrast, neutrophil/macrophage production began between 2 and 4 days and reached a peak at 6--8 days. The short duration of eosinophil production was evidently due to depletion of growth-factor-responsive cells.

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DC-SIGN signalling induced by Trichinella spiralis products contributes to the tolerogenic signatures of human dendritic cells

Scientific Reports ◽

10.1038/s41598-020-77497-x ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Jelena Cvetkovic ◽

Nataša Ilic ◽

Alisa Gruden-Movsesijan ◽

Sergej Tomic ◽

Ninoslav Mitic ◽

...

Keyword(s):

Dendritic Cells ◽

Trichinella Spiralis ◽

T Cell Response ◽

Toll Like Receptor ◽

Tolerogenic Dendritic Cells ◽

Toll Like Receptor 2 ◽

Secretory Products ◽

Human Dendritic Cells ◽

First Time

AbstractTolerogenic dendritic cells (tolDCs) are central players in the maintenance of immune tolerance and thereby have been identified as the most favourable candidates for cell therapy of autoimmune diseases. We have recently shown that excretory-secretory products (ES L1) released by Trichinella spiralis larvae induce stable human tolDCs in vitro via Toll-like receptor 2 (TLR2) and TLR4. However, engagement of these receptors did not fully explain the tolerogenic profile of DCs. Here, we observed for the first time that dendritic cell-specific ICAM-3 grabbing non-integrin (DC-SIGN) interacts with highly glycosylated ES L1 and contributes to the generation of ES L1-induced tolDCs. Blocking DC-SIGN interfered with the ES L1-induced higher expression of CD40 and CCR7 and the production of IL-10 and TGF-β by DCs. The cooperation of TLR2, TLR4 and DC-SIGN receptors is of importance for the capacity of DCs to prime T cell response toward Th2 and to induce expansion of CD4+CD25+Foxp3+ T cells, as well as for the production of IL-10 and TGF-β by these cells. Overall, these results indicate that induction of tolDCs by ES L1 involves engagement of multiple pattern recognition receptors namely, TLR2, TLR4 and DC-SIGN.

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Proteinases in Excretory-Secretory Products ofToxocara canisSecond-Stage Larvae: Zymography and Modeling Insights

BioMed Research International ◽

10.1155/2014/418708 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Gonzalo Ernesto González-Páez ◽

Fernando Alba-Hurtado ◽

Carlos Gerardo García-Tovar ◽

Raúl Argüello-García

Keyword(s):

Serine Proteinase ◽

Toxocara Canis ◽

Serine Proteinases ◽

Bodily Fluids ◽

Multiple Components ◽

Proteolytic Activities ◽

Secretory Products ◽

Ph Range ◽

Physiological Substrates

Components released in excretory-secretory products ofToxocara canislarvae (TES) include phosphatidylethanolamine-binding proteins (TES26), mucins (TES120, MUC2-5), and C-type lectins (TES32, TES70) and their biochemical, immunological, and diagnostic properties have been extensively studied albeit proteinase activities towards physiological substrates are almost unknown. Proteolytic activities in TES samples were first analyzed by gel electrophoresis with gelatin as substrate. Major activities of ~400, 120, and 32 kDa in TES were relatively similar over a broad pH range (5.5–9.0) and all these were of the serine-type as leupeptin abolished gelatinolysis. Further, the ~400 kDa component degraded all physiological substrates tested (laminin, fibronectin, albumin, and goat IgG) and the 120 kDa component degraded albumin and goat IgG while proteinases of lower MW (45, 32, and 26 kDa) only degraded laminin and fibronectin, preferentially at alkaline pH (9.0). By protein modeling approaches using the known sequences of TES components, only TES26 and MUC4 displayed folding patterns significantly related to reference serine proteinases. These data suggest that most of serine proteinase activities secretedin vitroby infective larvae ofT. canishave intriguing nature but otherwise help the parasite to affect multiple components of somatic organs and bodily fluids within the infected host.

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Effects of Trichinella spiralis and its excretory/secretory products on autophagy of host muscle cells in vivo and in vitro

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0009040 ◽

2021 ◽

Vol 15 (2) ◽

pp. e0009040

Author(s):

Xiaoxiang Hu ◽

Xiaolei Liu ◽

Xue Bai ◽

Li Yang ◽

Jing Ding ◽

...

Keyword(s):

Striated Muscle ◽

Cell Transformation ◽

Trichinella Spiralis ◽

Muscle Cells ◽

Microbial Infection ◽

Related Factors ◽

Parasitic Helminths ◽

Secretory Products

Trichinella spiralis (T. spiralis) is a widely distributed pathogenic microorganism that causes trichinellosis, a disease that has the potential of causing severe harm to their host. Numerous studies have demonstrated that autophagy can be triggered by microbial infection, such as bacteria, viruses, protozoa, and parasitic helminths. However, it’s still unknown whether autophagy can facilitate host resistance to T. spiralis infection. The present study examined the role of autophagy in striated muscle cell transformation following infection with T. spiralis in BALB/c mice. Transmission electron microscopy (TEM) was used to detect the production of the host diaphragm autophagosome after T. spiralis infection, and changes in the protein and transcriptional levels of autophagic marker proteins were also detected. The significance of autophagy in T. spiralis infection, namely inhibition of T. spiralis growth, was preliminarily evaluated by conducting in vivo experiments using autophagy inhibitors. Besides, we studied the effect of excretory-secretory products (ES) of T. spiralis on autophagy of C2C12 myoblasts. The changes in protein and gene expression levels in autophagy-related pathways in vitro and in vivo were measured as further evidence. The results showed that T. spiralis infection induced autophagy in the host muscle cells. Meanwhile, ES inhibited autophagy of myoblasts in vitro, but this did not affect the cell viability. The upregulation and downregulation of autophagy-related factors in skeletal muscle cells may indicate an adaptive mechanism providing a comfortable niche for the parasite.

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Differential Inhibition of Helicoverpa armigera (Hubner) Gut Proteinases by Proteinase Inhibitors of Okra and It's Wild Relatives

ISRN Biotechnology ◽

10.5402/2013/632173 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 3

Author(s):

Shilpa K. Udamale ◽

M. P. Moharil ◽

T. B. Ugale ◽

J. M. Mankar

Keyword(s):

Insect Resistance ◽

Proteinase Inhibitors ◽

Management Strategies ◽

Resistance Management ◽

Trypsin Inhibitors ◽

Wild Relatives ◽

Proteinase Activity ◽

Differential Inhibition ◽

Chymotrypsin Inhibitors

The seeds of ten genotypes and twenty-nine wild relatives of okra were analysed for the presence of trypsin, chymotrypsin, and Helicoverpa gut proteinases (HGPs) inhibitors (HGPIs), with the aim to identify potent inhibitors of H. armigera gut proteinases. Proteinase inhibitors (PIs) obtained from wild relatives of okra exhibited stronger inhibition of HGPs than the genotypes of okra. In in vitro inhibitory assay against HGPs, A. tuberculatus 90396 and 90515 showed high tryptic inhibitory (71.8% and 69.2%), chymotryptic inhibitory (68.5% and 66.2%), and Helicoverpa gut proteinase activity (70.2% and 68.2%). In electrophoretic profile showed the same variation in the number of trypsin inhibitors (TIs), chymotrypsin Inhibitors (CIs), and HGPIs isoforms with different intensities, whereas genotypes of okra mostly showed monomorphic profile. Maximum eight HGPIs isoforms were found in A. tuberculatus (90396 and 90515). In bioassay studies, significant reduction in weight of H. armigera larvae was found, when larvae fed on PIs obtained from A. tuberculatus (90396 and 90515). Thus, the result of the present investigation indicates that further exploration of PIs obtained from A. tuberculatus (90396 and 90515) will be helpful for developing PIs-based insect resistance management strategies.

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Trichinella spiralis Excretory–Secretory Products Stimulate Host Regulatory T Cell Differentiation through Activating Dendritic Cells

Cells ◽

10.3390/cells8111404 ◽

2019 ◽

Vol 8 (11) ◽

pp. 1404 ◽

Cited By ~ 4

Author(s):

Sun ◽

Guo ◽

Hao ◽

Zhan ◽

Huang ◽

...

Keyword(s):

Dendritic Cells ◽

T Cell ◽

Regulatory T Cell ◽

Trichinella Spiralis ◽

Treg Cells ◽

Chronic Infections ◽

Cell Responses ◽

Muscle Larvae ◽

Secretory Products

Trichinella spiralis maintains chronic infections within its host, involving a variety of immunomodulatory properties, the mechanisms of which have not been completely elucidated. In this study, we found that T. spiralis infection induced strong regulatory T cell responses through parasite excretory–secretory (ES) products, characterized by increase of CD4+CD25+Foxp3+ and CD4+CD25−Foxp3+ Treg cells accompanied by high levels of IL-10 and TGF-β. T. spiralis adult worm excretory–secretory products (AES) and muscle larvae excretory–secretory products (MES) were both able to activate BMDCs in vitro to facilitate their maturation and to create regulatory cytokines IL-10 and TGF-β. The T. spiralis AES- and MES-pulsed dendritic cells (DCs) possessed abilities not only to present antigens to sensitized CD4+ T cell to stimulate their proliferation but also to induce naive CD4+ T cells to differentiate to Treg cells secreting IL-10 and TGF-β. The passive transfer of T. spiralis AES- and MES-pulsed bone marrow-derived dendritic cells (BMDCs) conferred the naive mice to acquire the differentiation of Treg cells. T. spiralis AES possesses a better ability to induce Treg cells than did MES, although the latter has the ability to induce CD4+CD25−Foxp3+ Treg cells. The results obtained in this study suggested that T. spiralis ES products stimulate the differentiation of host Treg cells possibly through activating dendritic cells to create a regulatory environment that benefits the survival of the parasite in the host.

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Antigen production by encysted muscle larvae of Trichinella spiralis

Journal of Helminthology ◽

10.1017/s0022149x00034519 ◽

1985 ◽

Vol 59 (1) ◽

pp. 71-77 ◽

Cited By ~ 11

Author(s):

D. I. Pritchard

Keyword(s):

Trichinella Spiralis ◽

Exchange Chromatography ◽

Antigen Production ◽

Close Proximity ◽

Muscle Larvae ◽

Before And After ◽

Secretory Products ◽

Unlabelled Antibody

AbstractThe production of excretory-secretory antigens by encysted muscle larvae of Trichinella spiralis has been investigated immuno-histochemically using an antiserum raised by infection in rabbits and purified both before and after conjugation by ion-exchange chromatography. The specificity of the antibody for excretory-secretory products was demonstrated by the pattern of staining of live worms in vitro and the failure of the labelled antibody to stain dead, non-metabolizing worms. Using this labelled antibody, and unlabelled antibody in the immunoperoxidase system, the presence of parasite antigen-bearing cells in close proximity to encysted muscle larvae has been demonstrated. This is believed to be the first demonstration of antigen production by encysted muscle larvae in vivo. The implications of this observation to current concepts of immunity to Trichinella spiralis are discussed.

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Trichinella spiralisExcretory-Secretory Products Protect against Polymicrobial Sepsis by Suppressing MyD88 via Mannose Receptor

BioMed Research International ◽

10.1155/2014/898646 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 6

Author(s):

Linlin Du ◽

Lihua Liu ◽

Yang Yu ◽

Hui Shan ◽

Leiqing Li

Keyword(s):

Trichinella Spiralis ◽

Mannose Receptor ◽

Polymicrobial Sepsis ◽

Organ Injury ◽

Inflammatory Factors ◽

Control Group ◽

Mice Model ◽

Secretory Products

Trichinella spiralis(T. spiralis) or its excretory-secretory products (TsES) protect hosts from autoimmune diseases, which depend on inducing host T helper (Th) 2 immune response and inhibiting inflammatory factors. Sepsis is a systemic inflammatory response syndrome (SIRS) evoked by infection. Little is known about the effects of helminths or their excretory-secretory products on sepsis. Here, we investigated the effects of TsES in a mice model of polymicrobial sepsis. TsES improved survival, reduced organ injury, and enhanced bacterial clearance in septic mice. To investigate the molecular mechanism, macrophages from septic patients or the control group were incubated with TsES. TsES reduced sepsis-inducing inflammatory cytokines mediated by Toll-like receptors (TLR)in vitroby suppressing TLR adaptor-transducer myeloid differentiation factor 88 (MyD88) and nuclear factor- (NF-)-κB. Furthermore, TsES upregulated mannose receptor (MR) expression during sepsis. MR blocking attenuated the effects of TsES on MyD88 and NF-κB expression.In vivo, MR RNAi reduced the survival rate of septic mice treated with TsES, suggesting that TsES-mediated protection against polymicrobial sepsis is dependent on MR. Thus, TsES administration might be a potential therapeutic strategy for treating sepsis.

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Effects of the Human Immunodeficiency Virus (HIV) Proteinase Inhibitors Saquinavir and Indinavir on In Vitro Activities of Secreted Aspartyl Proteinases of Candida albicans Isolates from HIV-Infected Patients

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.43.8.2038 ◽

1999 ◽

Vol 43 (8) ◽

pp. 2038-2042 ◽

Cited By ~ 91

Author(s):

Hans C. Korting ◽

Martin Schaller ◽

Gabriele Eder ◽

Gerald Hamm ◽

Ursula Böhmer ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Candida Albicans ◽

Proteinase Inhibitors ◽

Oral Candidiasis ◽

Proteinase Activity ◽

Dependent Manner ◽

Immunodeficiency Virus ◽

Dose Dependent ◽

Pepstatin A

ABSTRACT The effects of therapeutically relevant concentrations of the human immunodeficiency virus (HIV) proteinase inhibitors saquinavir and indinavir on the in vitro proteinase activity of Candida albicans were investigated with isolates from HIV-infected and uninfected patients with oral candidiasis. After exposure to the HIV proteinase inhibitors, proteinase activity was significantly reduced in a dose-dependent manner. These inhibitory effects, which were similar to that of pepstatin A, and the reduced virulence phenotype in experimental candidiasis after application of saquinavir indicate the usefulness of these HIV proteinase inhibitors as potential anticandidal agents.

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Partial characterization of proteolytic enzymes in different developmental stages of Ostertagia ostertagi

Journal of Helminthology ◽

10.1017/s0022149x00013262 ◽

1993 ◽

Vol 67 (4) ◽

pp. 271-278 ◽

Cited By ~ 10

Author(s):

H. de Cock ◽

D. P. Knox ◽

E. Claerebout ◽

D. C. de Graaf

Keyword(s):

Proteinase Inhibitor ◽

Developmental Stages ◽

Proteolytic Enzymes ◽

Ostertagia Ostertagi ◽

Protein Substrates ◽

Stage Specificity ◽

Specific Manner ◽

Secretory Products

AbstractProteolytic enzymes present in extracts of third (L3) and fourth (L4) stage larvae and adults of the cattle nematode Ostertagia ostertagi were defined on the basis of pH optima and proteinase inhibitor sensitivity in spectrophotometric assays using azocasein and elastin-orcein as protein substrates. Evidence that different classes of proteinases are expressed in a stage specific manner was provided by the contrasting pH optima and inhibitor sensitivities shown by the enzymes in the different parasite stages. Stage specificity was confirmed by gelatin-substrate analysis. In addition, proteolytic activity was sought in the excretory/secretory products (ES) of the L4 following simple in vitro culture. Contrasting pH and inhibitor sensitivities as well as gelatin-substrate analysis showed that different proteinases were present in somatic L4 extracts and L4 ES products. The secreted proteinases may be useful targets for serodiagnosis or vaccination.

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