The publication of the first tick sialome (salivary gland transcriptome) heralded a new era of research of tick protease inhibitors, which represent important constituents of the proteins secreted via tick saliva into the host. Three major groups of protease inhibitors are secreted into saliva: Kunitz inhibitors, serpins, and cystatins. Kunitz inhibitors are anti-hemostatic agents and tens of proteins with one or more Kunitz domains are known to block host coagulation and/or platelet aggregation. Serpins and cystatins are also anti-hemostatic effectors, but intriguingly, from the translational perspective, also act as pluripotent modulators of the host immune system. Here we focus especially on this latter aspect of protease inhibition by ticks and describe the current knowledge and data on secreted salivary serpins and cystatins and their role in tick-host-pathogen interaction triad. We also discuss the potential therapeutic use of tick protease inhibitors.

• Klíčová slova
• cystatins, immunomodulation, protease inhibitors, serpins, tick-host interaction,
• MeSH
• cystatiny fyziologie   terapeutické užití   MeSH
• imunomodulace MeSH
• inhibitory proteas klasifikace   metabolismus   terapeutické užití   MeSH
• inhibitory serinových proteinas fyziologie   terapeutické užití   MeSH
• interakce hostitele a parazita MeSH
• klíšťata metabolismus   MeSH
• lidé MeSH
• serpiny fyziologie   terapeutické užití   MeSH
• sliny enzymologie   metabolismus   MeSH
• transkriptom MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• cystatiny MeSH
• inhibitory proteas MeSH
• inhibitory serinových proteinas MeSH
• serpiny MeSH

Ticks, as obligate hematophagous ectoparasites, impact greatly on animal and human health because they transmit various pathogens worldwide. Over the last decade, several cystatins from different hard and soft ticks were identified and biochemically analyzed for their role in the physiology and blood feeding lifestyle of ticks. All these cystatins are potent inhibitors of papain-like cysteine proteases, but not of legumain. Tick cystatins were either detected in the salivary glands and/or the midgut, key tick organs responsible for blood digestion and the expression of pharmacologically potent salivary proteins for blood feeding. For example, the transcription of two cystatins named HlSC-1 and Sialostatin L2 was highly upregulated in these tick tissues during feeding. Vaccinating hosts against Sialostatin L2 and Om-cystatin 2 as well as silencing of a cystatin gene from Amblyomma americanum significantly inhibited the feeding ability of ticks. Additionally, Om-cystatin 2 and Sialostatin L possessed strong host immunosuppressive properties by inhibiting dendritic cell maturation due to their interaction with cathepsin S. These two cystatins, together with Sialostatin L2 are the first tick cystatins with resolved three-dimensional structure. Sialostatin L, furthermore, showed preventive properties against autoimmune diseases. In the case of the cystatin Hlcyst-2, experimental evidence showed its role in tick innate immunity, since increased Hlcyst-2 transcript levels were detected in Babesia gibsoni-infected larval ticks and the protein inhibited Babesia growth. Other cystatins, such as Hlcyst-1 or Om-cystatin 2 are assumed to be involved in regulating blood digestion. Only for Bmcystatin was a role in tick embryogenesis suggested. Finally, all the biochemically analyzed tick cystatins are powerful protease inhibitors, and some may be novel antigens for developing anti-tick vaccines and drugs of medical importance due to their stringent target specificity.

• MeSH
• cystatiny farmakologie   MeSH
• inhibitory cysteinových proteinas farmakologie   MeSH
• klíšťata účinky léků   fyziologie   MeSH
• lidé MeSH
• molekulární modely MeSH
• molekulární sekvence - údaje MeSH
• sekvence aminokyselin MeSH
• sekvenční seřazení MeSH
• stravovací zvyklosti účinky léků   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• cystatiny MeSH
• inhibitory cysteinových proteinas MeSH

Tick saliva injected into the vertebrate host contains bioactive anti-proteolytic proteins from the cystatin family; however, the molecular basis of their unusual biochemical and physiological properties, distinct from those of host homologs, is unknown. Here, we present Ricistatin, a novel secreted cystatin identified in the salivary gland transcriptome of Ixodes ricinus ticks. Recombinant Ricistatin inhibited host-derived cysteine cathepsins and preferentially targeted endopeptidases, while having only limited impact on proteolysis driven by exopeptidases. Determination of the crystal structure of Ricistatin in complex with a cysteine cathepsin together with characterization of structural determinants in the Ricistatin binding site explained its restricted specificity. Furthermore, Ricistatin was potently immunosuppressive and anti-inflammatory, reducing levels of pro-inflammatory cytokines IL-6, IL-1β, and TNF-α and nitric oxide in macrophages; IL-2 and IL-9 levels in Th9 cells; and OVA antigen-induced CD4+ T cell proliferation and neutrophil migration. This work highlights the immunotherapeutic potential of Ricistatin and, for the first time, provides structural insights into the unique narrow selectivity of tick salivary cystatins determining their bioactivity.

• Klíčová slova
• Cystatins, Host–parasite interactions, Ixodes ricinus, Protease inhibition, Protein structure, Tick saliva,
• MeSH
• cystatiny * farmakologie   MeSH
• cystein metabolismus   MeSH
• endopeptidasy metabolismus   MeSH
• kathepsiny metabolismus   MeSH
• klíště * chemie   MeSH
• obratlovci MeSH
• proteasy metabolismus   MeSH
• slinné cystatiny chemie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cystatiny * MeSH
• cystein MeSH
• endopeptidasy MeSH
• kathepsiny MeSH
• proteasy MeSH
• slinné cystatiny MeSH

Two genes coding for cysteine peptidase inhibitors of the cystatin family (Om-cystatin 1 and 2) were isolated from a gut-specific cDNA library of the soft tick Ornithodoros moubata. Both cystatins were clearly down-regulated after a blood meal. Om-cystatin 1 is mainly expressed in the tick gut, while Om-cystatin 2 mRNA was also found in other tick tissues. Authentic Om-cystatin 2 was significantly more abundant than Om-cystatin 1 in the gut contents of fasting ticks and was associated with hemosome-derived residual bodies accumulated in the gut lumen. Om-cystatin 2 was also expressed by type 2 secretory cells in the salivary glands of unfed ticks. The inhibitory specificity of recombinant Om-cystatins 1 and 2 was tested with mammalian cysteine peptidases, as well as endogenous cysteine peptidases present in the tick gut. Both cystatins efficiently inhibited papain-like peptidases, including cathepsin B and H, but differed significantly in their affinity towards cathepsin C and failed to block asparaginyl endopeptidase. Our results suggest that the secreted cystatin isoinhibitors are involved in the regulation of multiple proteolytic targets in the tick digestive system and tick-host interaction.

• MeSH
• cystatiny chemie   genetika   metabolismus   MeSH
• DNA primery MeSH
• elektronová mikroskopie MeSH
• fluorescenční protilátková technika nepřímá MeSH
• klíšťata MeSH
• klonování DNA MeSH
• komplementární DNA MeSH
• molekulární sekvence - údaje MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• regulace genové exprese MeSH
• sekvence aminokyselin MeSH
• sekvence nukleotidů MeSH
• sekvenční homologie aminokyselin MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• cystatiny MeSH
• DNA primery MeSH
• komplementární DNA MeSH

We have previously demonstrated that two salivary cysteine protease inhibitors from the Borrelia burgdorferi (Lyme disease) vector Ixodes scapularis- namely sialostatins L and L2 - play an important role in tick biology, as demonstrated by the fact that silencing of both sialostatins in tandem results in severe feeding defects. Here we show that sialostatin L2 - but not sialostatin L - facilitates the growth of B. burgdorferi in murine skin. To examine the structural basis underlying these differential effects of the two sialostatins, we have determined the crystal structures of both sialostatin L and L2. This is the first structural analysis of cystatins from an invertebrate source. Sialostatin L2 crystallizes as a monomer with an 'unusual' conformation of the N-terminus, while sialostatin L crystallizes as a domain-swapped dimer with an N-terminal conformation similar to other cystatins. Deletion of the 'unusual' N-terminal five residues of sialostatin L2 results in marked changes in its selectivity, suggesting that this region is a particularly important determinant of the biochemical activity of sialostatin L2. Collectively, our results reveal the structure of two tick salivary components that facilitate vector blood feeding and that one of them also supports pathogen transmission to the vertebrate host.

• MeSH
• Borrelia burgdorferi patogenita   MeSH
• cystatiny chemie   izolace a purifikace   MeSH
• klíště chemie   mikrobiologie   MeSH
• lymeská nemoc přenos   MeSH
• molekulární modely MeSH
• molekulární sekvence - údaje MeSH
• myši inbrední C3H MeSH
• myši MeSH
• rekombinantní proteiny chemie   izolace a purifikace   MeSH
• sekvence aminokyselin MeSH
• sekvenční seřazení MeSH
• slinné cystatiny chemie   izolace a purifikace   MeSH
• terciární struktura proteinů MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Intramural MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Názvy látek
• cystatiny MeSH
• rekombinantní proteiny MeSH
• sialostatin L, Ixodes scapularis MeSH Prohlížeč
• slinné cystatiny MeSH

Cystatin is reported in the literature with increasing frequency as a new reliable parameter for estimates of glomerular filtration. The authors examined cystatin C by the PET method of DAKO Co. in 151 patients from the nephrological out-patient clinic. 91 patients had normal renal functions, 60 suffered from renal insufficiency of different severity. Between cystatin C and glomerular filtration assessed by creatinine clearance was a close correlation, R = -0.787 according to Pearson. The authors evaluated separately a group of 36 patients with glomerulonephritis, 34 diabetic patients with diabetic nephropathy, 38 patients with tubulointerstitial nephritis and 43 subjects with other kidney diseases. The groups did not differ significantly when compared with the whole group nor mutually (p = n.s.). The authors of the study confirmed that a good correlation of cystatin with creatinine filtration is not influenced by the type of basic nephrological disease. The effect of administration of insulin, antihypertensive drugs, cyclosporin A and glucocorticoids was not proved in the investigated group. The published method is accurate, not demanding from the technical aspect. The examined subject is not restricted by conditions ensuring the accuracy of assessment and seems thus useful and perspective for nephrological patients.

• MeSH
• biologické markery analýza   MeSH
• cystatin C MeSH
• cystatiny krev   MeSH
• dospělí MeSH
• hodnoty glomerulární filtrace * MeSH
• kreatinin metabolismus   MeSH
• lidé středního věku MeSH
• lidé MeSH
• nemoci ledvin metabolismus   patofyziologie   MeSH
• senioři MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• biologické markery MeSH
• CST3 protein, human MeSH Prohlížeč
• cystatin C MeSH
• cystatiny MeSH
• kreatinin MeSH

BACKGROUND: Serum level of cystatin C (MW 13,000) depends on the glomerular filtration and on the production by nucleated cells. S-cystatin C was proposed as a better glomerular filtration rate marker than serum creatinine or creatinine clearance. Possibility to avoid urine collection in children is another important advantage. The aim of the study was to estimate reliability of the test in the kidney transplant paediatric patients. METHODS AND RESULTS: We measured cystatin C on Monarch 2000 IL by particle-enhanced turbidimetric assay using commercial kit provided by DAKO. We analysed S-cystatin C levels in three groups: 19 children before kidney transplantation (A), 25 paediatric patients after kidney transplantation (B), 20 children hospitalized on intensive care unit (C). Creatinine was measured by enzymatic method on ADVIA 1650 Bayer. We demonstrated significant correlation between S-cystatin C and creatinine levels is both groups A (r2 = 0.865, P < 0.0001) and C (r2 = 0.812, P < 0.05). Correlation coefficient was much lower for group B (r2 = 0.689, P < 0.005). Cystatin C levels were compared with creatinine clearance (ml/s per 1.72 m2) and we found a very poor negative correlation in groups C (r2 = 0.24, P < 0.05) and B (r2 = 0.036, P < 0.006). In group A there was significant correlation between S-cystatin C and creatinine clearance (r2 = 0.769, P < 0.05). Negative correlation coefficient between calculated creatinine clearance (according Schwartz) and S-cystatin C was (r2 = 0.76, P < 0.005) in group B and (r2 = 0.75, P < 0.005) in group C. CONCLUSION: There is a significant correlation between S-cystatin C and creatinine levels in both groups: in group before kidney transplantation and in patients hospitalized at intensive care reanimation unit. In the group after kidney transplantation correlation coefficient is much lower.

• MeSH
• biologické markery krev   MeSH
• cystatin C MeSH
• cystatiny krev   MeSH
• dítě MeSH
• hodnoty glomerulární filtrace * MeSH
• kreatinin krev   MeSH
• lidé MeSH
• nemoci ledvin krev   patofyziologie   MeSH
• transplantace ledvin MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• biologické markery MeSH
• CST3 protein, human MeSH Prohlížeč
• cystatin C MeSH
• cystatiny MeSH
• kreatinin MeSH

Polyclonal rabbit antibodies to endogenous natural inhibitors of cysteine proteinases (cystatins) were used for their immunohistochemical demonstration in samples of breast cancers and in two breast cancer derived cell lines (MCF-7 and ZR-75-1). The influence of estrogen stimulation on the expression of these inhibitors was also studied. The results showed that all cystatins tested can be found equally inside carcinomatous cells or in surrounding connective tissue, as well as in both cell lines examined. Further, the expression of inhibitors can be regulated by estrogen, and a certain role of cystatins in the regulation of the mitotic activity and differentiation of mammary cells can be supposed.

• MeSH
• buněčné linie MeSH
• cystatin B MeSH
• cystatin C MeSH
• cystatiny * MeSH
• estradiol farmakologie   MeSH
• inhibitory cysteinových proteinas * MeSH
• inhibitory proteas analýza   biosyntéza   MeSH
• lidé MeSH
• nádorové buňky kultivované analýza   MeSH
• nádory prsu analýza   metabolismus   MeSH
• proteiny analýza   MeSH
• proteosyntéza MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• CST3 protein, human MeSH Prohlížeč
• CSTB protein, human MeSH Prohlížeč
• cystatin B MeSH
• cystatin C MeSH
• cystatiny * MeSH
• estradiol MeSH
• inhibitory cysteinových proteinas * MeSH
• inhibitory proteas MeSH
• proteiny MeSH

Fasciolosis is a worldwide parasitic disease of ruminants and an emerging human disease caused by the liver fluke Fasciola hepatica. The cystatin superfamily of cysteine protease inhibitors is composed of distinct families of intracellular stefins and secreted true cystatins. FhCyLS-2 from F. hepatica is an unusual member of the superfamily, where our sequence and 3D structure analyses in this study revealed that it combines characteristics of both families. The protein architecture demonstrates its relationship to stefins, but FhCyLS-2 also contains the secretion signal peptide and disulfide bridges typical of true cystatins. The secretion status was confirmed by detecting the presence of FhCyLS-2 in excretory/secretory products, supported by immunolocalization. Our high-resolution crystal structure of FhCyLS-2 showed a distinct disulfide bridging pattern and functional reactive center. We determined that FhCyLS-2 is a broad specificity inhibitor of cysteine cathepsins from both the host and F. hepatica, suggesting a dual role in the regulation of exogenous and endogenous proteolysis. Based on phylogenetic analysis that identified several FhCyLS-2 homologues in liver/intestinal foodborne flukes, we propose a new group within the cystatin superfamily called cystatin-like stefins.

• Klíčová slova
• cystatin, cysteine cathepsin, helminth parasite, protease inhibitor, protein evolution, protein structure, stefin,
• MeSH
• cystatiny * genetika   chemie   MeSH
• disulfidy MeSH
• Fasciola hepatica * genetika   MeSH
• fylogeneze MeSH
• proteiny červů chemie   genetika   MeSH
• sekvence aminokyselin MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• cystatiny * MeSH
• disulfidy MeSH
• proteiny červů MeSH

BACKGROUND: Cystatin C (CyC) is protein (m. w. 13 300), which is produced by nucleated cells, filtered through glomeruli and subsequently reabsorbed and degraded in tubuli. OBJECTIVE: To investigate changes in serum CyC concentration during two low-flux membrane haemodialyses (HD-I, HD-II) and relationship between serum CyC a creatinine concentrations. PATIENTS AND METHODS: Serum CyC was determined in 17 patients on chronic haemodialysis during HD-I and HD-II by immunonephelometric method (Dade Behring, Austria). RESULTS: Significant correlation between serum CyC and creatinine before HD-I and before/after HD-II was found (p < 0.001). Serum CyC before HD-I (median 6.3 mg/I, 95 % CI 5.5 - 6.7) increased after HD-I (7.1 mg/l, 6.1 - 8.9) (p < 0.001). Serum CyC before HD-II (6.4 mg/l, 5.8 - 7.2) increased after HD-II (8.0 mg/l, 7.3 - 9) (p < 0.001), while serum creatinine decreased after HD-I and HD-II (p < 0.001). There was correlation between the increase in serum CyC and albumin during HD-I (p < 0.001) and HD-II (p < 0.01). CONCLUSION: There was close correlation between serum CyC and creatinine before haemodialyses. Serum CyC increased after haemodialyses, due to CyC non-dialysability through low-flux membrane and haemoconcentration. Unlike creatininaemia, serum CyC reflects the residual renal function even after haemodialyses.

• MeSH
• cystatin C MeSH
• cystatiny krev   MeSH
• dialýza ledvin * MeSH
• dospělí MeSH
• kreatinin krev   MeSH
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• sérový albumin analýza   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• CST3 protein, human MeSH Prohlížeč
• cystatin C MeSH
• cystatiny MeSH
• kreatinin MeSH
• sérový albumin MeSH