LST1 is a small adaptor protein expressed in leukocytes of myeloid lineage. Due to the binding to protein tyrosine phosphatases SHP1 and SHP2 it was thought to have negative regulatory function in leukocyte signaling. It was also shown to be involved in cytoskeleton regulation and generation of tunneling nanotubes. LST1 gene is located in MHCIII locus close to many immunologically relevant genes. In addition, its expression increases under inflammatory conditions such as viral infection, rheumatoid arthritis and inflammatory bowel disease and its deficiency was shown to result in slightly increased sensitivity to influenza infection in mice. However, little else is known about its role in the immune system homeostasis and immune response. Here we show that similar to humans, LST1 is expressed in mice in the cells of the myeloid lineage. In vivo, its deficiency results in alterations in multiple leukocyte subset abundance in steady state and under inflammatory conditions. Moreover, LST1-deficient mice show significant level of resistance to dextran sodium sulphate (DSS) induced acute colitis, a model of inflammatory bowel disease. These data demonstrate that LST1 regulates leukocyte abundance in lymphoid organs and inflammatory response in the gut.

• MeSH
• biologické markery MeSH
• dendritické buňky imunologie   metabolismus   MeSH
• fosforylace MeSH
• genotyp MeSH
• intracelulární signální peptidy a proteiny genetika   metabolismus   MeSH
• kolitida etiologie   metabolismus   patologie   MeSH
• leukocyty imunologie   metabolismus   MeSH
• lidé MeSH
• lipopolysacharidy imunologie   MeSH
• makrofágy imunologie   metabolismus   MeSH
• membránové proteiny genetika   metabolismus   MeSH
• modely nemocí na zvířatech MeSH
• myši knockoutované MeSH
• myši MeSH
• náchylnost k nemoci MeSH
• regulace genové exprese * MeSH
• signální transdukce * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Out of three genotypes of Encephalitozoon cuniculi (I-III) available for experimental studies, E. cuniculi genotype I remains the less characterized. This study describes for the first time individual phases of microsporidiosis caused by E. cuniculi genotype I and efficacy of albendazole treatment in immunocompetent BALB/c and C57Bl/6 mice and immunodeficient SCID, CD4-/- and CD8-/- mice using molecular detection and quantification methods. We demonstrate asymptomatic infection despite an intense dissemination of microsporidia into most organs within the first weeks post infection, followed by a chronic infection characterized by significant microsporidia persistence in immunocompetent, CD4-/- and CD8-/- mice and a lethal outcome for SCID mice. Albendazole application led to loss E. cuniculi genotype I infection in immunocompetent mouse strains, decreased spore burden by half in CD4-/- and CD8-/- mice, and prolongation of survival of SCID mice. These results showed Encephalitozoon cuniculi genotype I infection extend and albendazole sensitivity was comparable to E. cuniculi genotype II, but the infection onset speed and mortality rate was similar to E. cuniculi genotype III. These imply that differences in the course of infection and the response to treatment depend not only on immunological status of the host, but also on the genotype causing the infection.

• MeSH
• albendazol aplikace a dávkování   MeSH
• antigeny CD4 genetika   MeSH
• antigeny CD8 genetika   MeSH
• antiinfekční látky aplikace a dávkování   MeSH
• Encephalitozoon cuniculi klasifikace   genetika   MeSH
• encephalitozoonóza imunologie   parazitologie   MeSH
• genotyp MeSH
• imunokompetence MeSH
• kvantitativní polymerázová řetězová reakce MeSH
• myši inbrední BALB C MeSH
• myši inbrední C57BL MeSH
• myši knockoutované MeSH
• myši SCID MeSH
• myši MeSH
• polymerázová řetězová reakce MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Hormone receptor (HR)+ breast cancer (BC) causes most BC-related deaths, calling for improved therapeutic approaches. Despite expectations, immune checkpoint blockers (ICBs) are poorly active in patients with HR+ BC, in part reflecting the lack of preclinical models that recapitulate disease progression in immunocompetent hosts. We demonstrate that mammary tumors driven by medroxyprogesterone acetate (M) and 7,12-dimethylbenz[a]anthracene (D) recapitulate several key features of human luminal B HR+HER2- BC, including limited immune infiltration and poor sensitivity to ICBs. M/D-driven oncogenesis is accelerated by immune defects, demonstrating that M/D-driven tumors are under immunosurveillance. Safe nutritional measures including nicotinamide (NAM) supplementation efficiently delay M/D-driven oncogenesis by reactivating immunosurveillance. NAM also mediates immunotherapeutic effects against established M/D-driven and transplantable BC, largely reflecting increased type I interferon secretion by malignant cells and direct stimulation of immune effector cells. Our findings identify NAM as a potential strategy for the prevention and treatment of HR+ BC.

• MeSH
• 9,10-dimethyl-1,2-benzanthracen MeSH
• analýza přežití MeSH
• experimentální nádory mléčných žláz chemicky indukované   imunologie   prevence a kontrola   MeSH
• imunoterapie metody   MeSH
• interferon typ I imunologie   metabolismus   MeSH
• karcinogeneze účinky léků   imunologie   MeSH
• lidé MeSH
• medroxyprogesteronacetát MeSH
• myši inbrední BALB C MeSH
• myši inbrední C57BL MeSH
• myši knockoutované MeSH
• nádory prsu imunologie   metabolismus   terapie   MeSH
• niacinamid aplikace a dávkování   MeSH
• progrese nemoci MeSH
• receptor erbB-2 imunologie   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

Of four genotypes of Encephalitozoon cuniculi, E. cuniculi genotype II is considered to represent a parasite that occurs in many host species in a latent asymptomatic form, whereas E. cuniculi genotype III seems to be more aggressive, and infections caused by this strain can lead to the death of even immunocompetent hosts. Although albendazole has been considered suitable for treatment of Encephalitozoon species, its failure in control of E. cuniculi genotype III infection has been reported. This study determined the effect of a 100× recommended daily dose of albendazole on an Encephalitozoon cuniculi genotype III course of infection in immunocompetent and immunodeficient mice and compared the results with those from experiments performed with a lower dose of albendazole and E. cuniculi genotype II. The administration of the regular dose of abendazole during the acute phase of infection reduced the number of affected organs in all strains of mice and absolute counts of spores in screened organs. However, the effect on genotype III was minor. Surprisingly, no substantial effect was recorded after the use of a 100× dose of albendazole, with larger reductions seen only in the number of affected organs and absolute counts of spores in all strains of mice, implying variations in albendazole resistance between these Encephalitozoon cuniculi genotypes. These results imply that differences in the course of infection and the response to treatment depend not only on the immunological status of the host but also on the genotype causing the infection. Understanding how microsporidia survive in hosts despite targeted antimicrosporidial treatment could significantly contribute to research related to human health.

• MeSH
• albendazol aplikace a dávkování   farmakologie   MeSH
• antifungální látky aplikace a dávkování   farmakologie   MeSH
• antigeny CD4 genetika   MeSH
• antigeny CD8 genetika   MeSH
• buněčné linie MeSH
• Cercopithecus aethiops MeSH
• Encephalitozoon cuniculi účinky léků   genetika   izolace a purifikace   MeSH
• encephalitozoonóza farmakoterapie   MeSH
• genotyp MeSH
• imunokompromitovaný pacient imunologie   MeSH
• mikrobiální testy citlivosti MeSH
• modely nemocí na zvířatech MeSH
• myši inbrední BALB C MeSH
• myši inbrední C57BL MeSH
• myši knockoutované MeSH
• myši SCID MeSH
• myši MeSH
• počet mikrobiálních kolonií MeSH
• Vero buňky MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Crohn's disease is linked to a decreased diversity in gut microbiota composition as a potential consequence of an impaired anti-microbial response and an altered polarization of T helper cells. Here, we evaluated the immunomodulatory properties of two potential probiotic strains, namely a Bifidobacterium animalis spp. lactis Bl 5764 and a Lactobacillus reuteri Lr 5454 strains. Both strains improved colitis triggered by either 2,4,6-trinitrobenzenesulfonic acid (TNBS) or Citrobacter rodentium infection in mice. Training of dendritic cells (DC) with Lr 5454 efficiently triggered IL-22 secretion and regulatory T cells induction in vitro, while IL-17A production by CD4+ T lymphocytes was stronger when cultured with DCs that were primed with Bl 5764. This strain was sufficient for significantly inducing expression of antimicrobial peptides in vivo through the Crohn's disease predisposing gene encoding for the nucleotide-binding oligomerization domain, containing protein 2 (NOD2). In contrast, NOD2 was dispensable for the impact on antimicrobial peptide expression in mice that were monocolonized with Lr 5454. In conclusion, our work highlights a differential mode of action of two potential probiotic strains that protect mice against colitis, providing the rational for a personalized supportive preventive therapy by probiotics for individuals that are genetically predisposed to Crohn's disease.

• MeSH
• antiflogistika nesteroidní farmakologie   MeSH
• Bifidobacterium animalis * MeSH
• Citrobacter rodentium patogenita   MeSH
• dendritické buňky fyziologie   MeSH
• enterobakteriální infekce mikrobiologie   MeSH
• gnotobiologické modely MeSH
• kolitida chemicky indukované   mikrobiologie   patologie   terapie   MeSH
• kyselina trinitrobenzensulfonová toxicita   MeSH
• Limosilactobacillus reuteri * MeSH
• modely nemocí na zvířatech MeSH
• myši inbrední BALB C MeSH
• myši inbrední C57BL MeSH
• myši knockoutované MeSH
• probiotika farmakologie   MeSH
• proteiny asociované s pankreatitidou genetika   MeSH
• regulační T-lymfocyty fyziologie   MeSH
• střevní mikroflóra MeSH
• T-lymfocyty pomocné-indukující fyziologie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The systemic anaphylactic reaction is a life-threatening allergic response initiated by activated mast cells. Sphingolipids are an essential player in the development and attenuation of this response. De novo synthesis of sphingolipids in mammalian cells is inhibited by the family of three ORMDL proteins (ORMDL1, 2, and 3). However, the cell and tissue-specific functions of ORMDL proteins in mast cell signaling are poorly understood. This study aimed to determine cross-talk of ORMDL2 and ORMDL3 proteins in IgE-mediated responses. To this end, we prepared mice with whole-body knockout (KO) of Ormdl2 and/or Ormdl3 genes and studied their role in mast cell-dependent activation events in vitro and in vivo. We found that the absence of ORMDL3 in bone marrow-derived mast cells (BMMCs) increased the levels of cellular sphingolipids. Such an increase was further raised by simultaneous ORMDL2 deficiency, which alone had no effect on sphingolipid levels. Cells with double ORMDL2 and ORMDL3 KO exhibited increased intracellular levels of sphingosine-1-phosphate (S1P). Furthermore, we found that concurrent ORMDL2 and ORMDL3 deficiency increased IκB-α phosphorylation, degranulation, and production of IL-4, IL-6, and TNF-α cytokines in antigen-activated mast cells. Interestingly, the chemotaxis towards antigen was increased in all mutant cell types analyzed. Experiments in vivo showed that passive cutaneous anaphylaxis (PCA), which is initiated by mast cell activation, was increased only in ORMDL2,3 double KO mice, supporting our in vitro observations with mast cells. On the other hand, ORMDL3 KO and ORMDL2,3 double KO mice showed faster recovery from passive systemic anaphylaxis, which could be mediated by increased levels of blood S1P presented in such mice. Our findings demonstrate that Ormdl2 deficiency potentiates the ORMDL3-dependent changes in mast cell signaling.

• MeSH
• anafylaxe etiologie   metabolismus   MeSH
• biologické markery MeSH
• chemotaxe imunologie   MeSH
• cytokiny metabolismus   MeSH
• exprese genu MeSH
• lysofosfolipidy krev   metabolismus   MeSH
• mastocyty imunologie   metabolismus   MeSH
• membránové proteiny chemie   nedostatek   genetika   metabolismus   MeSH
• multigenová rodina MeSH
• myši knockoutované MeSH
• myši MeSH
• náchylnost k nemoci MeSH
• pasivní kožní anafylaxe genetika   imunologie   MeSH
• sekvence aminokyselin MeSH
• sfingolipidy krev   metabolismus   MeSH
• sfingosin analogy a deriváty   krev   metabolismus   MeSH
• signální transdukce * MeSH
• vápník metabolismus   MeSH
• vápníková signalizace MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The coreceptor CD8αβ can greatly promote activation of T cells by strengthening T-cell receptor (TCR) binding to cognate peptide-MHC complexes (pMHC) on antigen presenting cells and by bringing p56Lck to TCR/CD3. Here, we demonstrate that CD8 can also bind to pMHC on the T cell (in cis) and that this inhibits their activation. Using molecular modeling, fluorescence resonance energy transfer experiments on living cells, biochemical and mutational analysis, we show that CD8 binding to pMHC in cis involves a different docking mode and is regulated by posttranslational modifications including a membrane-distal interchain disulfide bond and negatively charged O-linked glycans near positively charged sequences on the CD8β stalk. These modifications distort the stalk, thus favoring CD8 binding to pMHC in cis. Differential binding of CD8 to pMHC in cis or trans is a means to regulate CD8+ T-cell responses and provides new translational opportunities.

• MeSH
• aktivace lymfocytů imunologie   MeSH
• antigeny CD8 chemie   genetika   metabolismus   MeSH
• biologické modely MeSH
• CD8-pozitivní T-lymfocyty imunologie   metabolismus   MeSH
• histokompatibilní antigeny chemie   genetika   imunologie   MeSH
• interakční proteinové domény a motivy MeSH
• konformace proteinů MeSH
• molekulární modely MeSH
• multiproteinové komplexy chemie   imunologie   metabolismus   MeSH
• mutace MeSH
• myši knockoutované MeSH
• myši MeSH
• peptidy chemie   imunologie   metabolismus   MeSH
• sekvence aminokyselin MeSH
• vazba proteinů MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

AIMS: The transsulfuration pathway enzymes cystathionine beta-synthase (CBS) and cystathionine gamma-lyase are thought to be the major source of hydrogen sulfide (H2S). In this study, we assessed the role of CBS in H2S biogenesis. RESULTS: We show that despite discouraging enzyme kinetics of alternative H2S-producing reactions utilizing cysteine compared with the canonical condensation of serine and homocysteine, our simulations of substrate competitions at biologically relevant conditions suggest that cysteine is able to partially compete with serine on CBS, thus leading to generation of appreciable amounts of H2S. The leading H2S-producing reaction is condensation of cysteine with homocysteine, while cysteine desulfuration plays a dominant role when cysteine is more abundant than serine and homocysteine is limited. We found that the serine-to-cysteine ratio is the main determinant of CBS H2S productivity. Abundance of cysteine over serine, for example, in plasma, allowed for up to 43% of CBS activity being responsible for H2S production, while excess of serine typical for intracellular levels effectively limited such activity to less than 1.5%. CBS also produced lanthionine from serine and cysteine and a third of lanthionine coming from condensation of two cysteines contributed to the H2S pool. INNOVATION: Our study characterizes the H2S-producing potential of CBS under biologically relevant conditions and highlights the serine-to-cysteine ratio as the main determinant of H2S production by CBS in vivo. CONCLUSION: Our data clarify the function of CBS in H2S biogenesis and the role of thioethers as surrogate H2S markers. Antioxid. Redox Signal. 28, 311-323.

• MeSH
• alanin analogy a deriváty   chemie   metabolismus   MeSH
• biologické markery chemie   metabolismus   MeSH
• cystathionin-beta-synthasa chemie   metabolismus   MeSH
• cystein chemie   MeSH
• Haplorrhini MeSH
• homocystein chemie   MeSH
• katalýza MeSH
• kinetika MeSH
• myši knockoutované MeSH
• myši MeSH
• serin chemie   MeSH
• síra metabolismus   MeSH
• sulfan chemie   metabolismus   MeSH
• sulfidy chemie   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Previous findings showed that in mice, complete knockout of activity-dependent neuroprotective protein (ADNP) abolishes brain formation, while haploinsufficiency (Adnp+/-) causes cognitive impairments. We hypothesized that mutations in ADNP lead to a developmental/autistic syndrome in children. Indeed, recent phenotypic characterization of children harboring ADNP mutations (ADNP syndrome children) revealed global developmental delays and intellectual disabilities, including speech and motor dysfunctions. Mechanistically, ADNP includes a SIP motif embedded in the ADNP-derived snippet drug candidate NAP (NAPVSIPQ, also known as CP201), which binds to microtubule end-binding protein 3, essential for dendritic spine formation. Here, we established a unique neuronal membrane-tagged, GFP-expressing Adnp+/- mouse line allowing in vivo synaptic pathology quantification. We discovered that Adnp deficiency reduced dendritic spine density and altered synaptic gene expression, both of which were partly ameliorated by NAP treatment. Adnp+/-mice further exhibited global developmental delays, vocalization impediments, gait and motor dysfunctions, and social and object memory impairments, all of which were partially reversed by daily NAP administration (systemic/nasal). In conclusion, we have connected ADNP-related synaptic pathology to developmental and behavioral outcomes, establishing NAP in vivo target engagement and identifying potential biomarkers. Together, these studies pave a path toward the clinical development of NAP (CP201) for the treatment of ADNP syndrome.

• MeSH
• aminokyselinové motivy MeSH
• autistická porucha genetika   metabolismus   patologie   patofyziologie   MeSH
• biologické markery metabolismus   MeSH
• buněčná membrána genetika   metabolismus   patologie   MeSH
• chování zvířat MeSH
• dendritické trny metabolismus   patologie   MeSH
• homeodoménové proteiny MeSH
• lidé MeSH
• mikrotubuly genetika   metabolismus   patologie   MeSH
• modely neurologické * MeSH
• mutace MeSH
• myši knockoutované MeSH
• myši MeSH
• naftochinony farmakologie   MeSH
• proteiny nervové tkáně nedostatek   MeSH
• regulace genové exprese MeSH
• synapse metabolismus   patologie   MeSH
• syndrom MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• audiovizuální média MeSH
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

Fatty acid esters of hydroxy fatty acids (FAHFAs) are lipid mediators with promising antidiabetic and anti-inflammatory properties that are formed in white adipose tissue (WAT) via de novo lipogenesis, but their biosynthetic enzymes are unknown. Using a combination of lipidomics in WAT, quantitative trait locus mapping, and correlation analyses in rat BXH/HXB recombinant inbred strains, as well as response to oxidative stress in murine models, we elucidated the potential pathway of biosynthesis of several FAHFAs. Comprehensive analysis of WAT samples identified ∼160 regioisomers, documenting the complexity of this lipid class. The linkage analysis highlighted several members of the nuclear factor, erythroid 2 like 2 (Nrf2)-mediated antioxidant defense system (Prdx6, Mgst1, Mgst3), lipid-handling proteins (Cd36, Scd6, Acnat1, Acnat2, Baat), and the family of flavin containing monooxygenases (Fmo) as the positional candidate genes. Transgenic expression of Nrf2 and deletion of Prdx6 genes resulted in reduction of palmitic acid ester of 9-hydroxystearic acid (9-PAHSA) and 11-PAHSA levels, while oxidative stress induced by an inhibitor of glutathione synthesis increased PAHSA levels nonspecifically. Our results indicate that the synthesis of FAHFAs via carbohydrate-responsive element-binding protein-driven de novo lipogenesis depends on the adaptive antioxidant system and suggest that FAHFAs may link activity of this system with insulin sensitivity in peripheral tissues.

• MeSH
• bílá tuková tkáň enzymologie   metabolismus   MeSH
• biologické markery metabolismus   MeSH
• estery chemie   metabolismus   MeSH
• faktor 2 související s NF-E2 genetika   metabolismus   MeSH
• krysa rodu rattus MeSH
• kyselina palmitová chemie   metabolismus   MeSH
• kyseliny stearové chemie   metabolismus   MeSH
• metabolomika metody   MeSH
• myši inbrední C57BL MeSH
• myši knockoutované MeSH
• náhodné rozdělení MeSH
• oxidační stres * MeSH
• peroxiredoxin VI genetika   metabolismus   MeSH
• potkani inbrední BN MeSH
• potkani inbrední SHR MeSH
• potkani transgenní MeSH
• regulace genové exprese enzymů * MeSH
• stanovení celkové genové exprese MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH