RESUMEN
Mast cells are important for eradication of intestinal nematodes; however, their precise mechanisms of action have remained elusive, especially in the early phase of infection. We found that Spi-B-deficient mice had increased numbers of mast cells and rapidly expelled the Heligmosomoides polygyrus (Hp) nematode. This was accompanied by induction of interleukin-13 (IL-13)-producing group 2 innate lymphoid cells (ILC2) and goblet cell hyperplasia. Immediately after Hp infection, mast cells were rapidly activated to produce IL-33 in response to ATP released from apoptotic intestinal epithelial cells. In vivo inhibition of the P2X7 ATP receptor rendered the Spi-B-deficient mice susceptible to Hp, concomitant with elimination of mast cell activation and IL-13-producing ILC2 induction. These results uncover a previously unknown role for mast cells in innate immunity in that activation of mast cells by ATP orchestrates the development of a protective type 2 immune response, in part by producing IL-33, which contributes to ILC2 activation.
Asunto(s)
Helmintiasis/inmunología , Helmintiasis/parasitología , Helmintos/inmunología , Inmunidad Innata , Subgrupos Linfocitarios/inmunología , Mastocitos/inmunología , Adenosina Trifosfato/metabolismo , Animales , Comunicación Celular , Diferenciación Celular , Modelos Animales de Enfermedad , Resistencia a la Enfermedad/genética , Factor de Transcripción GATA2/genética , Factor de Transcripción GATA2/metabolismo , Expresión Génica , Helmintiasis/genética , Inmunofenotipificación , Interleucina-33/metabolismo , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/parasitología , Mucosa Intestinal/patología , Subgrupos Linfocitarios/citología , Subgrupos Linfocitarios/metabolismo , Masculino , Mastocitos/citología , Mastocitos/metabolismo , Ratones , Ratones Noqueados , Fenotipo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Transactivadores/genética , Transactivadores/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Memory T helper (mTh) cells play important roles in the reinfection of pathogens and drive the pathogenesis of diseases. While recent studies have characterized the pathogenic mTh2 cell subpopulations driving allergic inflammation, those that induce immune responses against helminth infection remain unknown. We found that IL-5-producing CXCR6+ST2+CD44+ mTh2 cells play a crucial role in the IL-33-dependent inhibition of the fecundity of helminth, whereas other ST2- mTh2 cells do not. Although both cell types induced the infiltration of granulocytes, especially eosinophils, into the lungs in response to helminth infection, the ST2+ mTh2 cell-induced eosinophils expressed higher levels of major basic protein (MBP), which is important for reducing the fecundity of Nippostrongylus brasiliensis (Nb), than ST2- mTh2 cell-induced ones. Notably, we also found that ST2+ Treg cells but not ST2- Treg cells suppressed CXCR6+ST2+ mTh2 cell-mediated immune responses. Taken together, these findings show that we identified a mechanism against helminth elicited by a subpopulation of IL-5-producing mTh2 cells through the accumulation of eosinophils strongly expressing MBP in the lungs.
Asunto(s)
Eosinófilos/inmunología , Fertilidad/inmunología , Memoria Inmunológica/inmunología , Proteína 1 Similar al Receptor de Interleucina-1/metabolismo , Proteína Básica de Mielina/metabolismo , Nippostrongylus/inmunología , Receptores CXCR6/metabolismo , Células Th2/inmunología , Animales , Eosinófilos/metabolismo , Eosinófilos/parasitología , Fertilidad/fisiología , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/prevención & control , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/parasitología , Ratones , Ratones Endogámicos BALB C , Receptores de Interleucina/metabolismo , Infecciones por Strongylida/complicaciones , Infecciones por Strongylida/parasitología , Linfocitos T Reguladores/inmunología , Células TH1/inmunología , Células TH1/metabolismo , Células Th2/metabolismoRESUMEN
Galactoseß1-4Fucose (GalFuc) is a unique disaccharide found in invertebrates including nematodes. A fungal galectin CGL2 suppresses nematode development by recognizing the galactoseß1-4fucose epitope. The Caenorhabditis elegans galectin LEC-6 recognizes it as an endogenous ligand and the Glu67 residue of LEC-6 is responsible for this interaction. We found that mammalian galectin-2 (Gal-2) also has a comparable glutamate residue, Glu52. In the present study, we investigated the potential nematode-suppressing activity of Gal-2 using C. elegans as a model and focusing on Gal-2 binding to the GalFuc epitope. Gal-2 suppressed C. elegans development whereas its E52D mutant (Glu52 substituted by Asp), galectin-1 and galectin-3 had little effect on C. elegans growth. Lectin-staining using fluorescently-labeled Gal-2 revealed that, like CGL2, it specifically binds to the C. elegans intestine. Natural C. elegans glycoconjugates were specifically bound by immobilized Gal-2. Western blotting with anti-GalFuc antibody showed that the bound glycoconjugates had the GalFuc epitope. Frontal affinity chromatography with pyridylamine-labeled C. elegans N-glycans disclosed that Gal-2 (but not its E52D mutant) recognizes the GalFuc epitope. Gal-2 also binds to the GalFuc-bearing glycoconjugates of Ascaris and the GalFuc epitope is present in the parasitic nematodes Nippostrongylus brasiliensis and Brugia pahangi. These results indicate that Gal-2 suppresses C. elegans development by binding to its GalFuc epitope. The findings also imply that Gal-2 may prevent infestations of various parasitic nematodes bearing the GalFuc epitope.
Asunto(s)
Caenorhabditis elegans/crecimiento & desarrollo , Disacáridos/química , Epítopos/química , Galectina 2/metabolismo , Animales , Ascaris suum/crecimiento & desarrollo , Ascaris suum/metabolismo , Sitios de Unión , Biomphalaria , Caenorhabditis elegans/metabolismo , Disacáridos/metabolismo , Epítopos/metabolismo , Galectina 2/química , Células HeLa , Humanos , Ratones , Ratones Endogámicos ICRRESUMEN
Nutritional zinc deficiency leads to immune dysfunction and aggravates inflammation. However, the underlying mechanism remains unknown. In this study, the relationship between macrophage subtypes (M1 and M2) and helper T lymphocytes (Th1 and Th2) was investigated using the spleen from rats fed zinc-deficient or standard diet. In experiment I, 5-week-old male Sprague-Dawley rats were fed a zinc-deficient diet (without zinc additives) or a standard diet (containing 0·01% zinc) for 6 weeks. In experiment II, the rats were divided into four groups: one group was fed a standard diet for 6 weeks; two groups were fed zinc-deficient diets and were injected three times a week with either saline or interleukin-4 (IL-4) (zinc-deficient/IL-4 i.p.); a fourth group (zinc-deficient/standard) was fed a zinc-deficient diet for 6 weeks followed by a standard diet for 4 weeks. In experiment I; GATA-binding protein 3 (GATA-3) protein level, M2 macrophage, CD3+ CD8+ cells, and IL-4/IL-13-positive cells significantly decreased in the spleens of the zinc-deficient group. Additionally, IL-1ß and macrophage inflammatory protein-1α (MIP-1α) mRNA levels significantly increased in the splenic macrophages of the zinc-deficient group. In experiment II; M2 macrophages, CD3+ CD8+ cells, IL-4/IL-13-positive cells, and GATA-3 protein levels significantly increased in the spleens of the zinc-deficient/IL-4 i.p. and zinc-deficient/standard groups. Furthermore, IL-1ß and MIP-1α mRNA levels decreased in the splenic macrophages of the zinc-deficient/IL-4 i.p. and zinc-deficient/standard groups. Zinc deficiency-induced aggravated inflammation is related to Th2 lymphocytes and followed by the association with loss of GATA-3, IL-4 and anti-inflammatory M2 macrophages. Importantly, IL-4 injection or zinc supplementation can reverse the effects of zinc deficiency on immune function.
Asunto(s)
Inflamación/inmunología , Macrófagos/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Zinc/deficiencia , Animales , Biomarcadores/análisis , Quimiocina CCL3/análisis , Quimiocina CCL3/genética , Quimiocina CCL3/inmunología , Quimiocinas/análisis , Quimiocinas/genética , Quimiocinas/inmunología , Citocinas/análisis , Citocinas/genética , Citocinas/inmunología , Dieta , Inflamación/tratamiento farmacológico , Interleucina-4/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/patología , Masculino , ARN Mensajero/análisis , ARN Mensajero/genética , ARN Mensajero/inmunología , Ratas , Ratas Sprague-Dawley , Bazo/efectos de los fármacos , Bazo/inmunología , Bazo/patología , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Linfocitos T Colaboradores-Inductores/patología , Zinc/administración & dosificación , Zinc/farmacologíaRESUMEN
Natural killer (NK) cells are known to be activated by Th1-type cytokines, such as IL-2, -12, or -18, and they secrete a large amount of IFN-γ that accelerates Th1-type responses. However, the roles of NK cells in Th2-type responses have remained unclear. Because IL-4 acts as an initiator of Th2-type responses, we examined the characteristics of NK cells in mice overexpressing IL-4. In this study, we report that IL-4 overexpression induces distinctive characteristics of NK cells (B220(high)/CD11b(low)/IL-18Rα(low)), which are different from mature conventional NK (cNK) cells (B220(low)/CD11b(high)/IL-18Rα(high)). IL-4 overexpression induces proliferation of tissue-resident macrophages, which contributes to NK cell proliferation via production of IL-15. These IL-4-induced NK cells (IL4-NK cells) produce higher levels of IFN-γ, IL-10, and GM-CSF, and exhibit high cytotoxicity compared with cNK cells. Furthermore, incubation of cNK cells with IL-15 and IL-4 alters their phenotype to that similar to IL4-NK cells. Finally, parasitic infection, which typically causes strong Th2-type responses, induces the development of NK cells with characteristics similar to IL4-NK cells. These IL4-NK-like cells do not develop in IL-4Rα KO mice by parasitic infection. Collectively, these results suggest a novel role of IL-4 in immune responses through the induction of the unique NK cells.
Asunto(s)
Citotoxicidad Inmunológica , Interleucina-15/inmunología , Interleucina-4/inmunología , Células Asesinas Naturales/inmunología , Activación de Linfocitos , Infecciones por Strongylida/inmunología , Animales , Antígeno CD11b/genética , Antígeno CD11b/inmunología , Proliferación Celular , Regulación de la Expresión Génica , Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-10/genética , Interleucina-10/inmunología , Interleucina-15/genética , Interleucina-15/farmacología , Interleucina-4/genética , Interleucina-4/farmacología , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/parasitología , Antígenos Comunes de Leucocito/genética , Antígenos Comunes de Leucocito/inmunología , Macrófagos/inmunología , Macrófagos/parasitología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Nippostrongylus/inmunología , Nippostrongylus/patogenicidad , Receptores de Interleucina-18/genética , Receptores de Interleucina-18/inmunología , Receptores de Interleucina-4/deficiencia , Receptores de Interleucina-4/genética , Receptores de Interleucina-4/inmunología , Transducción de Señal , Infecciones por Strongylida/genética , Infecciones por Strongylida/parasitologíaRESUMEN
Schistosoma mansoni (Sm) is known to exert protective effects against various allergic and autoimmune disorders. It has been reported that this parasite protects NOD mice from spontaneous type 1 diabetes (T1D) and ameliorates streptozotocin (STZ)-induced T1D in wild-type mice. Here, we tried to clarify the anti-diabetic mechanisms of Sm in the latter model. Sm infection partially prevented the degradation of pancreatic islets and hyperglycemia in multiple low-dose (MLD) STZ-treated mice. Neither Treg cell depletion nor genetic absences of IL-10 and/or STAT6 abrogated the anti-hyperglycemic effects of Sm. Among M2 macrophage markers, Arg-1 and Ym1, but not Retnla, remained up-regulated in the pancreatic lymph nodes and in the spleens of STAT6/IL-10 double deficient (DKO) mice. Collectively, it is suggested that Sm exerts anti-diabetic effects on this experimental T1D model via Treg/IL-4/IL-13/IL-10-independent mechanisms. Augmented expressions of Arg-1 and Ym1 in the lymphoid organs adjacent to pancreas may be relevant to the anti-diabetic effects of Sm.
Asunto(s)
Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 1/genética , Interleucina-10/genética , Factor de Transcripción STAT6/genética , Esquistosomiasis mansoni/complicaciones , Animales , Biomphalaria , Glucemia/metabolismo , Diabetes Mellitus Experimental/parasitología , Diabetes Mellitus Experimental/prevención & control , Diabetes Mellitus Tipo 1/inducido químicamente , Diabetes Mellitus Tipo 1/parasitología , Regulación de la Expresión Génica , Inyecciones Intraperitoneales , Interleucina-10/metabolismo , Interleucina-13/genética , Interleucina-13/metabolismo , Interleucina-4/genética , Interleucina-4/metabolismo , Islotes Pancreáticos/patología , Ganglios Linfáticos/citología , Ganglios Linfáticos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Endogámicos NOD , Ratones Noqueados , Factor de Transcripción STAT6/metabolismo , Esquistosomiasis mansoni/sangre , Organismos Libres de Patógenos Específicos , Bazo/inmunología , Estreptozocina/administración & dosificación , Linfocitos T/inmunologíaRESUMEN
Developmental processes of hematopoietic cells are orchestrated by transcriptional networks. GATA-1, the founding member of the GATA family of transcription factors, has been demonstrated to play crucial roles in the differentiation of erythroid cells, magakaryocytes, eosinophils, and mast cells. However, the role of GATA-1 in basophils remains elusive. Here we show that basophils abundantly express Gata1 mRNAs, and that siRNA-mediated knockdown of Gata1 resulted in impaired production of IL-4 by basophils in response to the stimulation with IgE plus antigens. ΔdblGATA mice that carry the mutated Gata1 promoter and are widely used for functional analysis of eosinophils owing to their selective loss of eosinophils showed a decreased number of basophils with reduced expression of Gata1 mRNAs. The number of basophil progenitors in bone marrow was reduced in these mice, and the generation of basophils from their bone marrow cells in culture with IL-3 or thymic stromal lymphopoietin was impaired. ΔdblGATA basophils responded poorly ex vivo to stimulation with IgE plus antigens compared with wild-type basophils as assessed by degranulation and production of IL-4 and IL-6. Moreover, ΔdblGATA mice showed impaired responses in basophil-mediated protective immunity against intestinal helminth infection. Thus, ΔdblGATA mice showed numerical and functional aberrancy in basophils in addition to the known deficiency of eosinophils. Our findings demonstrate that GATA-1 plays a key role in the generation and function of basophils and underscore the need for careful distinction of the cell lineage responsible for each phenotype observed in ΔdblGATA mice.
Asunto(s)
Basófilos/inmunología , Diferenciación Celular/inmunología , Factor de Transcripción GATA1/metabolismo , Células Madre Hematopoyéticas/inmunología , Animales , Basófilos/metabolismo , Cartilla de ADN/genética , Citometría de Flujo , Factor de Transcripción GATA1/genética , Técnicas de Silenciamiento del Gen , Células Madre Hematopoyéticas/citología , Interleucina-4/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Mucin is a major component of mucus on gastrointestinal mucosa. Mucin alteration in the host is considered to be the principal event for expulsion of intestinal helminths. However, it is unclear what mucin alterations are induced by various helminth infections. In this study, the alterations of mouse small intestinal mucin after infection with two nematodes, Nippostrongylus brasiliensis and Heligmosomoides polygyrus, which parasitize the jejunal epithelium, and a cestode, Vampirolepis nana, which parasitizes the ileal epithelium, were examined biochemically and histologically using two anti-mucin monoclonal antibodies (mAbs), HCM31 and PGM34, which recognize Sd(a) antigen, NeuAcα2-3(GalNAcß1-4)Galß1-4GlcNAcß-, and sulphated H type 2 antigen, Fucα1-2Galß1-4GlcNAc(6SO3H)ß-, respectively. The goblet cell mucins that reacted with HCM31 increased conspicuously on the jejunal mucosa concurrently with expulsion of N. brasiliensis. Increased levels of HCM31-reactive mucins were observed in the jejunal mucosa after H. polygyrus infection, despite the ongoing parasitism. Goblet cell mucins that reacted with PGM34 increased on the ileal mucosa during V. nana parasitism. Small intestinal goblet cells reacting with the two mAbs were not observed in non-infected mice, although sialomucins and sulfomucins were abundantly present. Additionally, the number of ileal goblet cells that reacted with the two mAbs was increased at the time of expulsion of heterophyid trematode. These results indicate that the type of specific acidic mucins expressed after infection varies among species of intestinal helminth, and, furthermore, that the relationship with worm expulsion is also different.
Asunto(s)
Mucosa Intestinal/metabolismo , Yeyuno/metabolismo , Mucinas/metabolismo , Nematospiroides dubius/fisiología , Nippostrongylus/fisiología , Sialomucinas/metabolismo , Infecciones por Strongylida/metabolismo , Infecciones por Strongylida/parasitología , Animales , Células Caliciformes/metabolismo , Células Caliciformes/parasitología , Células Caliciformes/patología , Humanos , Mucosa Intestinal/parasitología , Mucosa Intestinal/patología , Yeyuno/parasitología , Yeyuno/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Mucinas/genética , Sialomucinas/genética , Infecciones por Strongylida/genética , Infecciones por Strongylida/patologíaRESUMEN
We established a diphtheria toxin (DT)-based conditional deletion system using Il4 enhancer elements previously shown to be specific for IL-4 production in mast cells (MCs) or basophils (Mas-TRECK and Bas-TRECK mice). DT treatment of Bas-TRECK mice resulted in specific deletion of basophils, whereas both MCs and basophils were deleted in Mas-TRECK mice. DT-treated Mas-TRECK mice had impaired passive cutaneous anaphylaxis, IgE-mediated passive systemic anaphylaxis, and IgE-mediated chronic allergic inflammation, whereas DT-treated Bas-TRECK mice had impaired IgE-mediated chronic allergic inflammation. Using these mice, we also sought to tease out the role of MCs and basophils in airway hyperresponsiveness (AHR). Although MC deletion resulted in a slight increase in basal Ag-specific IgE levels and significant increases in basal IgE levels, we found that this deletion markedly impaired the AHR effector phase and was accompanied by decreased histamine levels. By contrast, basophil deletion had no effect on the AHR effector phase or on IgE production induced by systemic OVA immunization. Our results, using these newly established Mas-TRECK and Bas-TRECK models, demonstrated an indispensable role for MCs as effector cells in AHR.
Asunto(s)
Basófilos/inmunología , Hiperreactividad Bronquial/inmunología , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Mastocitos/inmunología , Hipersensibilidad Respiratoria/inmunología , Animales , Toxina Diftérica/farmacología , Interleucina-4/biosíntesis , Ratones , Ratones Endogámicos C57BL , Anafilaxis Cutánea Pasiva/inmunologíaRESUMEN
Some parasitic helminths are known to protect their hosts from allergic and autoimmune disorders. Here, we tested the effects of a gastrointestinal nematode, Heligmosomoides polygyrus (Hp), on streptozotocin (STZ)-induced type 1 diabetes (T1D) in mice. Hp infection significantly suppressed hyperglycemia induced by multiple low-dose administration of STZ, but did not affect hyperglycemia induced by single high-dose administration of STZ. In the multiple low dose model, Hp infection prevented a decrease in pancreatic islet size. The augmentation of TNF-α and IL-1ß expression in the pancreas was abrogated by Hp infection. The genetic absence of IL-10 or STAT6 did not abrogate the anti-hyperglycemic effect of Hp. Hp has a suppressive effect on immune mechanism-mediated experimental T1D via Th2 polarization-independent mechanisms.
Asunto(s)
Diabetes Mellitus Experimental/inmunología , Diabetes Mellitus Tipo 1/inmunología , Interleucina-10/inmunología , Nematospiroides dubius/inmunología , Factor de Transcripción STAT6/inmunología , Infecciones por Strongylida/inmunología , Animales , Citocinas/metabolismo , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Tipo 1/complicaciones , Interferón gamma/deficiencia , Interferón gamma/genética , Interleucina-10/deficiencia , Interleucina-10/genética , Islotes Pancreáticos/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Factor de Transcripción STAT6/deficiencia , Factor de Transcripción STAT6/genética , Índice de Severidad de la Enfermedad , Organismos Libres de Patógenos Específicos , Infecciones por Strongylida/complicacionesRESUMEN
Basophils are the rarest granulocytes and are recognized as critical cells for type 2 immune responses. However, their differentiation pathway remains to be fully elucidated. Here, we assess the ontogenetic trajectory of basophils by single-cell RNA sequence analysis. Combined with flow cytometric and functional analyses, we identify c-Kit-CLEC12Ahi pre-basophils located downstream of pre-basophil and mast cell progenitors (pre-BMPs) and upstream of CLEC12Alo mature basophils. The transcriptomic analysis predicts that the pre-basophil population includes previously-defined basophil progenitor (BaP)-like cells in terms of gene expression profile. Pre-basophils are highly proliferative and respond better to non-IgE stimuli but less to antigen plus IgE stimulation than do mature basophils. Although pre-basophils usually remain in the bone marrow, they emerge in helminth-infected tissues, probably through IL-3-mediated inhibition of their retention in the bone marrow. Thus, the present study identifies pre-basophils that bridge the gap between pre-BMPs and mature basophils during basophil ontogeny.
Asunto(s)
Basófilos , Transcriptoma , Diferenciación Celular/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Perfilación de la Expresión GénicaRESUMEN
The caliber and magnitude of T cell responses are regulated by costimulatory molecules following the engagement of TCRs and MHC molecules. B7-DC has the highest homology with B7-H1 in the B7 family, and both of them bind an immunoregulatory molecule, programmed death 1. Previous studies have demonstrated that B7-DC stimulates T cell proliferation and CTL generation, which sharply contrasts the inhibitory role of B7-H1. Th2 cytokines prompt B7-DC expression, which in turn enhances Th1 responses. In this study, we used an intestinal nematode, Nippostrongylus brasiliensis, to induce strong Th2 responses and to evaluate B7-DC function under Th2-polarizing conditions in vivo. By either blocking B7-DC expression during N. brasiliensis infection or by examining N. brasiliensis-infected B7-DC knockout mice, we observed enhanced eosinophilia, the overproduction of serum IgE, and increased Th2 cytokine production along with decreased Th1 cytokine production (particularly IFN-gamma production), indicating that B7-DC inhibits Th2 responses. Our results further demonstrate that the inhibition of Th2 responses by B7-DC occurs independently of programmed death 1 but conceivably acts through an as yet unknown alternative receptor that enhances Th1 responses. Although the deficiency of B7-DC expression that enhanced the production of IL-13 paradoxically resulted in better protection against N. brasiliensis infection, our results show that B7-DC plays an important role in bolstering a robust Th1 response that is required for effective antiviral and anticancer immunity, even under a strong Th2-polarizing environment induced by N. brasiliensis infection.
Asunto(s)
Antígeno B7-1/fisiología , Nippostrongylus/inmunología , Infecciones por Strongylida/inmunología , Células Th2/inmunología , Animales , Antígeno B7-1/genética , Células Cultivadas , Eosinofilia/inmunología , Eosinofilia/parasitología , Retroalimentación Fisiológica , Inmunoglobulina E/biosíntesis , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Ratones Transgénicos , Proteína 2 Ligando de Muerte Celular Programada 1 , Células Th2/metabolismo , Células Th2/parasitologíaRESUMEN
BACKGROUND: Tuberculosis is a chronic infection caused by Mycobacterium tuberculosis (M.tb), which needs proper macrophage activation for control. It has been debated whether the co-infection with helminth will affect the immune response to mycobacterial infection. OBJECTIVE: To determine the effect of sequential co-infection of Heligmosomoides polygyrus (H.pg) nematodes and M.tb on T cell responses, macrophages polarization and lung histopathological changes. METHOD: This study used 49 mice divided into 7 treatment groups, with different sequence of infection of M.tb via inhalation and H.pg via oral ingestion for 8 and 16 weeks. T cells response in the lung, intestine, and peripheral blood were determined by flow cytometry. Cytokines (IL-4, IFN-γ, TGB-ß1, and IL-10) were measured in peripheral blood using ELISA. Lung macrophage polarization were determined by the expression of iNOS (M1) or Arginase 1 (M2). Mycobacterial count were done in lung tissue. Lung histopathology were measured using Dorman's semiquantitative score assessing peribronchiolitis, perivasculitis, alveolitis, and granuloma formation. RESULT: M.tb infection induced Th1 response and M1 macrophage polarization, while H.pg infection induced Th2 and M2 polarization. In sequential co-infection, the final polarization of macrophage was dictated by the sequence of co-infection. However, all groups with M.tb infection showed the same degree of mycobacterial count in lung tissues and lung tissue histopathological changes. CONCLUSION: Sequential co-infection of H.pg and M.tb induces different T cell response which leads to different macrophage polarization in lung tissue. Helminth infection induced M2 lung macrophage polarization, but did not cause different mycobacterial count nor lung histopathological changes.
Asunto(s)
Pulmón , Activación de Macrófagos/inmunología , Macrófagos Alveolares/inmunología , Mycobacterium tuberculosis/inmunología , Nematospiroides dubius/inmunología , Infecciones por Strongylida , Tuberculosis , Animales , Recuento de Células , Polaridad Celular/inmunología , Coinfección/inmunología , Coinfección/microbiología , Coinfección/parasitología , Citocinas/sangre , Modelos Animales de Enfermedad , Inmunidad Celular , Pulmón/inmunología , Pulmón/patología , Ratones , Infecciones por Strongylida/inmunología , Infecciones por Strongylida/parasitología , Linfocitos T/inmunología , Tuberculosis/inmunología , Tuberculosis/microbiologíaRESUMEN
BACKGROUND: Trichuris suis ova (TSO), with the potential to modulate the human immune system, have been tested for therapeutic application in autoimmune and allergic diseases such as inflammatory bowel disease (IBD). Previous clinical studies were limited to European and American participants, whereas Asian populations have not been well documented. In this study, a clinical trial was conducted to examine the safety and tolerability of TSO administration among a healthy Japanese population. METHODS: The study was a randomized, double-blind, placebo-controlled trial held at Jikei University Hospital, Tokyo. Twelve volunteers were stratified into three groups receiving different doses of TSO (TSO 1000, 2500, and 7500) and another into the control group. These cases were limited to healthy Japanese men aged over 20 years old. Single doses of medicinal TSO or placebo were given to three participants of each group. All participants were followed up to 56 days after ingestion. During the follow-up period, clinical practitioners checked each participant at the clinic at 7, 14, 28, and 56 days post-ingestion (dpi). Clinical symptoms were evaluated using questionnaire-based self-reporting, which participants filled at every visit. Blood samples were drawn at 7, 14, 28, and 56 dpi. Fecal samples were collected at 28 and 56 dpi. RESULTS: During the study period, twelve healthy Japanese male volunteers were enrolled. All participants completed the follow-up period. No severe adverse events were observed during the study period in all groups. Three participants in the TSO 1000, 2500, and 7500 groups had mild to moderate abdominal symptoms, diarrhea, bloating, and appetite loss during the observation period. One participant in the placebo group presented with mild diarrhea. Microscopic examination identified no parasite ova in any fecal samples. Blood sample examination indicated elevated eosinophil count in several cases, especially in the groups with the higher dose of TSO. No extra-abdominal symptoms were present in all cases. CONCLUSIONS: Healthy Japanese people tolerated all doses of TSO without any severe adverse events. On the other hand, mild to moderate abdominal symptoms were observed in several participants. This study suggested that the medicinal use of TSO in Japan is relatively safe, and close follow-up is recommended for sustainable usage.
Asunto(s)
Enfermedades Autoinmunes/terapia , Hipersensibilidad/terapia , Enfermedades Inflamatorias del Intestino/terapia , Terapia con Helmintos/efectos adversos , Trichuris , Adulto , Animales , Enfermedades Autoinmunes/inmunología , Método Doble Ciego , Humanos , Hipersensibilidad/inmunología , Enfermedades Inflamatorias del Intestino/inmunología , Japón , MasculinoRESUMEN
The cryptic parasite Sparganum proliferum proliferates in humans and invades tissues and organs. Only scattered cases have been reported, but S. proliferum infection is always fatal. However, S. proliferum's phylogeny and life cycle remain enigmatic. To investigate the phylogenetic relationships between S. proliferum and other cestode species, and to examine the mechanisms underlying pathogenicity, we sequenced the entire genomes of S. proliferum and a closely related non-life-threatening tapeworm Spirometra erinaceieuropaei. Additionally, we performed larvae transcriptome analyses of S. proliferum plerocercoid to identify genes involved in asexual reproduction in the host. The genome sequences confirmed that the S. proliferum has experienced a clearly distinct evolutionary history from S. erinaceieuropaei. Moreover, we found that nonordinal extracellular matrix coordination allows asexual reproduction in the host, and loss of sexual maturity in S. proliferum are responsible for its fatal pathogenicity to humans. Our high-quality reference genome sequences should be valuable for future studies of pseudophyllidean tapeworm biology and parasitism.
Asunto(s)
Plerocercoide/genética , Animales , Secuencia de Bases/genética , Proliferación Celular/genética , Cestodos/clasificación , Cestodos/genética , Infecciones por Cestodos/genética , Infecciones por Cestodos/parasitología , Genoma/genética , Humanos , Larva/clasificación , Larva/genética , Estadios del Ciclo de Vida/genética , Filogenia , Plerocercoide/clasificación , Spirometra/clasificación , Spirometra/genéticaRESUMEN
Malaria and intestinal nematode infection are widespread and co-infection frequently occurs. We investigated whether co-infected intestinal nematodes modulate immunity against co-existing malaria parasites. Infection of C57BL/6 mice with Plasmodium yoelii 17XNL (Py) was transient and self-limiting, but preceding infection with Heligmosomoides polygyrus (Hp), a mouse intestinal nematode, exacerbated malaria resulting in higher parasite burdens and poor survival of the mice. Co-infection with Hp led to reduced Py-responsive proliferation and IFN-gamma production of spleen cells, and higher activation of CD4(+)CD25(+)Foxp3(+) Treg. In vivo depletion of Treg recovered anti-Py immunity and rescued co-infected mice from exacerbated malaria. However, we did not observe any obvious ex vivo activation of Treg by either Hp products or living worms. Our results suggest that intestinal nematodes moderate host immune responses during acute malaria infection by aggressive activation of Treg. Elucidation of the mechanisms of Treg activation in situ is a target for future analyses.
Asunto(s)
Factores de Transcripción Forkhead/metabolismo , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Malaria/inmunología , Nematospiroides dubius/inmunología , Plasmodium yoelii/inmunología , Infecciones por Strongylida/inmunología , Linfocitos T Reguladores/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Antígenos Helmínticos/inmunología , Recuento de Células , Concanavalina A/farmacología , Células Dendríticas/inmunología , Eritrocitos/inmunología , Eritrocitos/parasitología , Tolerancia Inmunológica/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Interferón gamma/metabolismo , Subunidad alfa del Receptor de Interleucina-2/inmunología , Activación de Linfocitos/inmunología , Depleción Linfocítica , Malaria/complicaciones , Malaria/parasitología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Parasitemia , Bazo/citología , Bazo/inmunología , Infecciones por Strongylida/complicaciones , Análisis de Supervivencia , Linfocitos T Reguladores/citología , Linfocitos T Reguladores/metabolismoRESUMEN
Rodents belonging to the subfamily Gerbillinae and living in the Xinjiang-Uygur autonomous region of China were collected in field surveys between 2001 and 2003. We found four Meriones species, including M. chengi M. liycus, M. meridianus, and M. tamariscinus, as well as related species from different genera, Rhombomys opimus and Brachiones przewaliskii For phylogenetic analyses of these gerbilline species, DNA sequences of parts of the mitochondrial cytochrome b (Cytb) and cytochrome c oxidase subunit II (COII) genes were examined with the neighbor Joining, maximum parsimony, maximum likelihood, and Bayesian inference methods. Our phylogenetic analyses suggest that the genus Meriones is not monophyletic and place M. tamaricinus as the sister taxon to a clade comprising Brachiones, Psammomys, Rhombomys, and the other Meriones species. The remaining Meriones species separate into three lineages: M. meridianus (including M. chengi), Meriones unguiculatus, and a clade that includes multiple Meriones species originating from Asia, the Middle East, and Africa. The phylogenetic relationships among the genera Brachines, Meriones, Psammomys, and Rhombomys remain ambiguous, probably due to the saturation of mutations that occurs in fast-evolving mitochondrial DNA. In addition, intraspecific variation was observed for M. meridianus, and this mostly correlated with collection localities, i.e., the northern and southern parts of the Xinjiang region. This variation corresponded to interspecific levels of divergence among other lineages of Meriones. Interestingly, no differences were observed in either the Cytb or COII gene sequences isolated from M. chengi collected from the Turfan Basin in the north and those from M. meridianus in the south, suggesting that M. chengi may be a synonym of M. meridianus.
Asunto(s)
Citocromos b/genética , Complejo IV de Transporte de Electrones/genética , Gerbillinae/genética , Mitocondrias/metabolismo , Filogenia , Animales , China , Regulación de la Expresión Génica , Mitocondrias/genéticaRESUMEN
The 5'-upsteam region of the genomic gene and cDNA encoding interleukin 4 (IL-4) has been isolated and sequenced from the inbred mouse strain MSKR derived from a Japanese wild mouse using polymerase chain reaction (PCR) methodology. The cDNA sequence of IL-4 of MSKR was found to contain several nucleotide alterations, which result in amino acid substitutions, in comparison with that of inbred mouse BALB/c. In MSKR, IL-4 was expressed at high levels in thymus and spleen as revealed by reverse transcriptase PCR method and Northern hybridization. The tissue-specific expression profile was quite similar to that of laboratory mice.
Asunto(s)
ADN Complementario/metabolismo , Regulación de la Expresión Génica , Interleucina-4/genética , Animales , Animales Endogámicos , Secuencia de Bases , Clonación Molecular , Interleucina-4/fisiología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Homología de Secuencia de Ácido Nucleico , Timo/citología , Distribución TisularRESUMEN
Expulsion of parasitic gastrointestinal nematodes requires diverse effector mechanisms coordinated by a Th2-type response. The evolutionarily conserved JmjC protein; Myc Induced Nuclear Antigen (Mina) has been shown to repress IL4, a key Th2 cytokine, suggesting Mina may negatively regulate nematode expulsion. Here we report that expulsion of the parasitic nematode Trichuris muris was indeed accelerated in Mina deficient mice. Unexpectedly, this was associated not with an elevated Th2- but rather an impaired Th1-type response. Further reciprocal bone marrow chimera and conditional KO experiments demonstrated that retarded parasite expulsion and a normal Th1-type response both required Mina in intestinal epithelial cells (IECs). Transcriptional profiling experiments in IECs revealed anti-microbial α-defensin peptides to be the major target of Mina-dependent retention of worms in infected mice. In vitro exposure to recombinant α-defensin peptides caused cytotoxic damage to whipworms. These results identify a latent IEC-intrinsic anthelmintic pathway actively constrained by Mina and point to α-defensins as important effectors that together with Mina may be attractive therapeutic targets for the control of nematode infection.
Asunto(s)
Células Epiteliales/metabolismo , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Trichuris/inmunología , Animales , Citocinas/análisis , Células Epiteliales/citología , Intestinos/citología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas de Neoplasias/deficiencia , Proteínas Nucleares/deficiencia , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/farmacología , Proteínas Recombinantes/uso terapéutico , Células TH1/citología , Células TH1/inmunología , Células TH1/metabolismo , Células Th2/citología , Células Th2/inmunología , Células Th2/metabolismo , Transcriptoma , Tricuriasis/tratamiento farmacológico , Tricuriasis/inmunología , Tricuriasis/patología , Trichuris/efectos de los fármacos , Trichuris/patogenicidad , alfa-Defensinas/genética , alfa-Defensinas/metabolismoRESUMEN
Immunological memory is central to adaptive immunity and protection from disease. Changing metabolic demands as antigen-specific T cells transition from effector to memory cells have been well documented, but the cell-specific pathways and molecules that govern this transition are poorly defined. Here we show that genetic deletion of ACC1, a rate-limiting enzyme in fatty acid biosynthesis, enhances the formation of CD4+ T memory cells. ACC1-deficient effector helper T (Th) cells have similar metabolic signatures to wild-type memory Th cells, and expression of the gene encoding ACC1, Acaca, was inversely correlated with a memory gene signature in individual cells. Inhibition of ACC1 function enhances memory T cell formation during parasite infection in mice. Using single-cell analyses we identify a memory precursor-enriched population (CCR7hiCD137lo) present during early differentiation of effector CD4+ T cells. Our data indicate that fatty acid metabolism directs cell fate determination during the generation of memory CD4+ T cells.