Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 19 de 19
Filter
1.
J Virol ; 93(15)2019 08 01.
Article in English | MEDLINE | ID: mdl-31092574

ABSTRACT

Myxovirus resistance 1 (Mx1) is an interferon-induced gene that encodes a GTPase that plays an important role in the defense of mammalian cells against influenza A and other viruses. The Mx1 protein can restrict a number of viruses independently of the expression of other interferon-induced genes. Mx genes are therefore considered to be an important part of the innate antiviral immune response. However, the possible impact of Mx expression in the hematopoietic cellular compartment has not been investigated in detail in the course of a viral infection. To address this, we performed bone marrow chimera experiments using congenic B6.A2G Mx1+/+ and B6.A2G Mx1-/- mice to study the effect of Mx1 expression in cells of hematopoietic versus nonhematopoietic origin. Mx1+/+ mice were protected and Mx1-/- mice were susceptible to influenza A virus challenge infection, regardless of the type of bone marrow cells (Mx1+/+ or Mx1-/- ) the animals had received. Infection with Thogoto virus, however, revealed that Mx1-/- mice with a functional Mx1 gene in the bone marrow compartment showed reduced liver pathology compared with Mx1-/- mice that had been grafted with Mx1-/- bone marrow. The reduced pathology in these mice was associated with a reduction in Thogoto virus titers in the spleen, lung, and serum. Moreover, Mx1+/+ mice with Mx1-/- bone marrow failed to control Thogoto virus replication in the spleen. Mx1 in the hematopoietic cellular compartment thus contributes to protection against Thogoto virus infection.IMPORTANCE Mx proteins are evolutionarily conserved in vertebrates and can restrict a wide range of viruses in a cell-autonomous way. The contribution to antiviral defense of Mx1 expression in hematopoietic cells remains largely unknown. We show that protection against influenza virus infection requires Mx1 expression in the nonhematopoietic cellular compartment. In contrast, Mx1 in bone marrow-derived cells is sufficient to control disease and virus replication following infection with a Thogoto virus. This indicates that, in addition to its well-established antiviral activity in nonhematopoietic cells, Mx1 in hematopoietic cells can also play an important antiviral function. In addition, cells of hematopoietic origin that lack a functional Mx1 gene contribute to Thogoto virus dissemination and associated disease.


Subject(s)
Bone Marrow Cells/immunology , Immunity, Innate , Immunologic Factors/metabolism , Myxovirus Resistance Proteins/metabolism , Orthomyxoviridae Infections/immunology , Thogotovirus/immunology , Animals , Bone Marrow/virology , Immunologic Factors/deficiency , Influenza A virus/immunology , Lung/virology , Mice, Inbred C57BL , Mice, Knockout , Myxovirus Resistance Proteins/deficiency , Orthomyxoviridae Infections/pathology , Serum/virology , Spleen/virology , Viral Load
2.
Clin Microbiol Infect ; 23(8): 576.e1-576.e5, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28192236

ABSTRACT

OBJECTIVES: Screening for primary immunodeficiencies (PIDs) in adults is recommended after two severe bacterial infections. We aimed to evaluate if screening should be performed after the first invasive infection in young adults. METHODS: Eligible patients were retrospectively identified using hospital discharge and bacteriology databases in three centres during a 3-year period. Eighteen to 40-year-old patients were included if they had experienced an invasive infection with encapsulated bacteria commonly encountered in PIDs (Streptococcus pneumoniae (SP), Neisseria meningitidis (NM), Neisseria gonorrhoeae (NG), Haemophilus influenzae (HI), or group A Streptococcus (GAS)). They were excluded in case of general or local predisposing factors. Immunological explorations and PIDs diagnoses were retrieved from medical records. Serum complement and IgG/A/M testings were systematically proposed at the time of study to patients with previously incomplete PID screening. RESULTS: The study population comprised 38 patients. Thirty-six had experienced a first invasive episode and a PID was diagnosed in seven (19%): two cases of common variable immunodeficiency revealed by SP bacteraemia, one case of idiopathic primary hypogammaglobulinaemia, and two cases of complement (C6 and C7) deficiency revealed by NM meningitis, one case of IgG2/IgG4 subclasses deficiency revealed by GAS bacteraemia, and one case of specific polysaccharide antibody deficiency revealed by HI meningitis. Two patients had previously experienced an invasive infection before the study period: in both cases, a complement deficiency was diagnosed after a second NM meningitis and a second NG bacteraemia, respectively. CONCLUSION: PID screening should be considered after a first unexplained invasive encapsulated-bacterial infection in young adults.


Subject(s)
Bacteremia/etiology , Bacteremia/immunology , Complement System Proteins/deficiency , Immunologic Deficiency Syndromes/complications , Immunologic Deficiency Syndromes/diagnosis , Meningitis, Bacterial/etiology , Meningitis, Bacterial/immunology , Adolescent , Adult , Female , Humans , Immunologic Factors/deficiency , Male , Mass Screening/methods , Prevalence , Retrospective Studies , Young Adult
3.
J Virol ; 90(19): 8780-94, 2016 10 01.
Article in English | MEDLINE | ID: mdl-27440901

ABSTRACT

UNLABELLED: Host cells respond to viral infections by producing type I interferon (IFN), which induces the expression of hundreds of interferon-stimulated genes (ISGs). Although ISGs mediate a protective state against many pathogens, the antiviral functions of the majority of these genes have not been identified. IFITM3 is a small transmembrane ISG that restricts a broad range of viruses, including orthomyxoviruses, flaviviruses, filoviruses, and coronaviruses. Here, we show that alphavirus infection is increased in Ifitm3(-/-) and Ifitm locus deletion (Ifitm-del) fibroblasts and, reciprocally, reduced in fibroblasts transcomplemented with Ifitm3. Mechanistic studies showed that Ifitm3 did not affect viral binding or entry but inhibited pH-dependent fusion. In a murine model of chikungunya virus arthritis, Ifitm3(-/-) mice sustained greater joint swelling in the ipsilateral ankle at days 3 and 7 postinfection, and this correlated with higher levels of proinflammatory cytokines and viral burden. Flow cytometric analysis suggested that Ifitm3(-/-) macrophages from the spleen were infected at greater levels than observed in wild-type (WT) mice, results that were supported by experiments with Ifitm3(-/-) bone marrow-derived macrophages. Ifitm3(-/-) mice also were more susceptible than WT mice to lethal alphavirus infection with Venezuelan equine encephalitis virus, and this was associated with greater viral burden in multiple organs. Collectively, our data define an antiviral role for Ifitm3 in restricting infection of multiple alphaviruses. IMPORTANCE: The interferon-induced transmembrane protein 3 (IFITM3) inhibits infection of multiple families of viruses in cell culture. Compared to other viruses, much less is known about the antiviral effect of IFITM3 on alphaviruses. In this study, we characterized the antiviral activity of mouse Ifitm3 against arthritogenic and encephalitic alphaviruses using cells and animals with a targeted gene deletion of Ifitm3 as well as deficient cells transcomplemented with Ifitm3. Based on extensive virological analysis, we demonstrate greater levels of alphavirus infection and disease pathogenesis when Ifitm3 expression is absent. Our data establish an inhibitory role for Ifitm3 in controlling infection of alphaviruses.


Subject(s)
Alphavirus Infections/immunology , Chikungunya virus/immunology , Encephalitis Virus, Venezuelan Equine/immunology , Immunologic Factors/metabolism , Membrane Proteins/metabolism , Alphavirus Infections/pathology , Alphavirus Infections/virology , Animals , Chikungunya virus/physiology , Cytokines/metabolism , Disease Models, Animal , Encephalitis Virus, Venezuelan Equine/physiology , Fibroblasts/immunology , Fibroblasts/virology , Gene Deletion , Genetic Complementation Test , Immunologic Factors/deficiency , Macrophages/virology , Membrane Proteins/deficiency , Mice , Mice, Knockout , Viral Load , Virus Internalization/drug effects
6.
Arthritis Rheum ; 64(5): 1338-44, 2012 May.
Article in English | MEDLINE | ID: mdl-22076784

ABSTRACT

OBJECTIVE: To assess the copy number variation of complement C4A and C4B genes in patients with rheumatoid arthritis (RA). METHODS: DNA samples were obtained from 299 patients and controls and analyzed for copy number variation of total complement C4, C4A, and C4B genes. The results were compared by chi-square analysis, and odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. RESULTS: Chi-square analysis revealed similar distribution patterns of total C4 alleles in RA patients (n = 160), non-RA patients (n = 88), and healthy controls (n = 51). There was no trend toward C4A deficiency as in lupus. Significant differences in C4B distribution were observed in RA patients, in whom an ∼2-fold increase in the frequency of homozygous and/or heterozygous C4B deficiency (0 or 1 allele) (40%) was present relative to non-RA patients or healthy controls (both 21.6%). C4B deficiency was more frequent in seropositive RA patients than in seronegative RA patients (44% versus 31%). The odds of C4B deficiency were 2.99 (95% CI 1.58-5.65) (P = 0.0006) in seropositive RA patients relative to non-RA controls. These findings were confirmed in a larger healthy control cohort, yielding an OR of 1.83 (95% CI 1.21-2.76) (P = 0.0056). The association of the shared epitope with C4B deficiency was significantly greater in seropositive RA patients than in non-seropositive RA controls (96% versus 54.5%) (P < 0.0001), suggesting that C4B deficiency interacts with the shared epitope in the development of seropositive RA. CONCLUSION: Our findings indicate a relationship between C4B copy number variation and RA that approximates that seen between C4A copy number variation and lupus. The concurrence of C4B deficiency and the shared epitope in seropositive RA may have broad implications for our understanding of RA pathogenesis.


Subject(s)
Arthritis, Rheumatoid/genetics , Complement C4b/genetics , Genetic Predisposition to Disease , Immunologic Factors/genetics , Adult , Aged , Aged, 80 and over , Arthritis, Rheumatoid/immunology , Complement C4a/genetics , Complement C4b/deficiency , Female , Gene Dosage , Genetic Variation , Haplotypes , Humans , Immunologic Factors/deficiency , Lupus Erythematosus, Systemic/genetics , Lupus Erythematosus, Systemic/immunology , Male , Middle Aged , Young Adult
7.
Rev. cuba. invest. bioméd ; 30(4): 501-510, sep.-dic. 2011.
Article in Spanish | LILACS | ID: lil-615419

ABSTRACT

La autoinmunidad se caracteriza por una pérdida de la tolerancia inmunológica que produce la destrucción de células y tejidos propios. El sistema del complejo mayor de histocompatibilidad posee una fuerte asociación con las enfermedades autoinmunes aunque determinados genes que codifican para citoquinas y moléculas coestimuladoras incrementan la susceptibilidad genética. Estudios de concordancia entre gemelos monocigóticos demuestran el papel de los factores ambientales en la aparición de las enfermedades autoinmunes. A pesar de los avances científicos producidos en esta área de investigación, los mecanismos subyacentes de estas afecciones son desconocidos. El objetivo de este trabajo es exponer de forma sintetizada el papel de los factores genéticos, inmunológicos y ambientales en la autoinmunidad


The autoimmunity is characterized by a loss of immunologic tolerance producing the destruction of cells and own tissues. The major complex system of histocompatibility has a close association with the autoimmune diseases although determined genes codifying for cytokines and co-stimulators molecules increase the genetic susceptibility. Concordance studies among monozygotic twins demonstrate the role of environmental factors in appearance of autoimmune diseases. Despite the scientific advances achieved in this research field, the underlying mechanisms of these affections are unknown. The objective of present paper is to expose in a summarized way the role of the genetic, immunologic and environmental factors in autoimmunity


Subject(s)
Autoimmunity/physiology , Immunologic Factors/deficiency , Gene-Environment Interaction , Genetic Predisposition to Disease
8.
Rev. cuba. invest. bioméd ; 30(4)sep.-dic. 2011. tab, ilus
Article in Spanish | CUMED | ID: cum-56515

ABSTRACT

La autoinmunidad se caracteriza por una pérdida de la tolerancia inmunológica que produce la destrucción de células y tejidos propios. El sistema del complejo mayor de histocompatibilidad posee una fuerte asociación con las enfermedades autoinmunes aunque determinados genes que codifican para citoquinas y moléculas coestimuladoras incrementan la susceptibilidad genética. Estudios de concordancia entre gemelos monocigóticos demuestran el papel de los factores ambientales en la aparición de las enfermedades autoinmunes. A pesar de los avances científicos producidos en esta área de investigación, los mecanismos subyacentes de estas afecciones son desconocidos. El objetivo de este trabajo es exponer de forma sintetizada el papel de los factores genéticos, inmunológicos y ambientales en la autoinmunidad(AU)


The autoimmunity is characterized by a loss of immunologic tolerance producing the destruction of cells and own tissues. The major complex system of histocompatibility has a close association with the autoimmune diseases although determined genes codifying for cytokines and co-stimulators molecules increase the genetic susceptibility. Concordance studies among monozygotic twins demonstrate the role of environmental factors in appearance of autoimmune diseases. Despite the scientific advances achieved in this research field, the underlying mechanisms of these affections are unknown. The objective of present paper is to expose in a summarized way the role of the genetic, immunologic and environmental factors in autoimmunity(AU)


Subject(s)
Autoimmunity/physiology , Genetic Predisposition to Disease , Gene-Environment Interaction , Immunologic Factors/deficiency
10.
Gerontology ; 57(1): 28-32, 2011.
Article in English | MEDLINE | ID: mdl-20110662

ABSTRACT

Epidemiologic studies report an increase in food allergies in industrialized countries, but mainly focus on children and young adults. This leads to the impression that food allergies do not occur in the older population. However, age-related changes dramatically affect both the innate as well as the adaptive immune system - a phenomenon known as immunosenescence. Deficiencies in micronutrients, especially zinc and iron, as well as vitamin D, in the elderly may also contribute to the development of allergies. A further risk factor of the elderly in developing food allergies could also be the decreased digestive ability of the stomach due to atrophic gastritis or anti-ulcer medication. In these settings, undigested proteins may persist and become allergenic. In fact, mouse models indicate that these pharmaceuticals support the induction of Th2 responses not only in young adult, but also in aged animals. Previous reports have already suggested that allergies are underdiagnosed among the elderly. Based on our own recent study conducted in a geriatric nursing home, we also suggest that food allergies may be underestimated.


Subject(s)
Aging/immunology , Food Hypersensitivity/etiology , Adult , Aged , Allergens/pharmacokinetics , Animals , Child , Food Hypersensitivity/immunology , Humans , Immunologic Factors/deficiency , Immunologic Factors/immunology , Mice , Micronutrients/deficiency , Micronutrients/immunology , Permeability/drug effects , Proton Pump Inhibitors/adverse effects , Vitamin D Deficiency/complications , Vitamin D Deficiency/immunology
11.
Arch. alerg. inmunol. clin ; 41(2): 49-56, 2011. ilus
Article in Spanish | LILACS | ID: biblio-964929

ABSTRACT

Objetivo. Investigar si componentes de la inmunidad innata están involucrados en la iniciación/perpetuación de las anormalidades estructurales observadas en la capa de Bowman y el estroma superficial de la córnea de pacientes con queratopatía climática esferoidea (QCE). Materiales y métodos. En el estudio participaron 8 pacientes con QCE y 12 individuos sanos del Departamento El Cuy, Provincia de Río Negro, y 10 individuos sanos de la ciudad de Córdoba. Todos ellos, luego de firmar el consentimiento informado, recibieron un examen oftalmológico completo y se recolectaron muestras de lágrima para estudiar las concentraciones de diferentes citocinas, niveles y formas de metaloproteinasas de matriz (MMPs), y el inhibidor natural de MMPs (TIMP-1). Se realizó microscopía confocal in vivo (MCF) en algunos pacientes y controles. Biopsias de córneas provenientes de pacientes que fueron tratados con queratoplastia penetrante también fueron estudiadas mediante inmunohistoquímica (IHQ). Resultados. Los resultados de MCF indicaron claramente una progresión en la cantidad de depósitos a nivel subepitelial, a medida que la enfermedad avanza. El daño progresivo de las fibras nerviosas sub basales y estromales en los estadios 2 y 3 se correlaciona con pérdida de la sensibilidad corneal. Además de estas alteraciones, observamos que el número de células dendríticas (CD) en el limbo corneal aumentó significativamente a medida que la QCE progresa. En lágrimas de pacientes con QCE se detectaron concentraciones significativamente superiores de citocinas proinflamatorias (IL1ß e IL-8) que en individuos controles (p<0,005). No se halló IL-2, IL-17, IL-4, IL-13 ni IL-10 en pacientes y ni controles. Las actividades de gelatinasas (MMP-9 y -2) fueron significativamente mayores en QCE que en los controles (p<0,001), mientras que los niveles de TIMP-1 fueron significativamente menores en los pacientes (p<0,05). La concentración de MMP-8 fue mayor en controles pero los niveles de esta colagenasa-2 fueron 30 veces superiores, tanto en QCE como controles, con respecto a los valores de los individuos de un centro urbano. Mediante IHC observamos reactividad para MMP-9 en la mayoría de las células epiteliales, solamente en córneas con QCE. Conclusión. Demostramos un rol protagónico del eje citocinas proinflamatorias - gela-tinasas en el desarrollo de la QCE. Los altos niveles de IL-1ß e IL-8 en lágrimas de pacientes facilitan la producción de MMP-8 y gelatinasas, y los efectos de las mismas se exacerban, ya que los pacientes tienen bajos niveles de sus inhibidores naturales (TIMP-1). La MMP-9, además de degradar componentes de la matriz extracelular, cataliza la activación postranscripcional de IL-1ß, potenciando el proceso inflamatorio. Estos resultados son los primeros en explicar mecanismos inmunológicos involucrados en la etiopatogénesis de la QCE y aportan nuevas alternativas para el desarrollo de terapias preventivas utilizando inhibidores de IL-1ß y/o gelatinasas(AU)


Objective. To investigate whether components of innate immunity are involved in the initiation / perpetuation of the structural abnormalities observed in Bowman's layer and superficial stroma of the córnea of patients with Climatic droplet keratopathy (CDK). Materials and Methods. The study included 8 CDK patients and 12 healthy individuals from Department El Cuy, Province of Río Negro, and 10 healthy subjects from the city of Córdoba. All of them, after signing informed consent, received a thorough eye exam and tear samples were collected to study the concentrations of different cytokines, and levels and forms of matrix metalloproteinases (MMPs) and their natural inhibitor (TIMP-1). In vivo confocal microscopy (CFM) was performed in some patients and controls. Corneal biopsies from CDK patients treated with penetrating keratoplasty were also studied by immunohistochemistry (IHC). Results. CFM results clearly indicated a progression in the amount of deposits at corneal sub epithelial level as the disease progresses. The progressive damage in the nerve plexus in stages 2 and 3 correlated with a loss of corneal sensitivity. In addition to these alterations, we observed that the number of dendritic cells (DC) in the limbus increased significantly as the disease progresses.In tears of patients with CDK we detected significantly higher concentrations of pro-inflammatory cytokines (IL-1ß and IL-8) than in control subjects (p < 0.005). We found no IL-2, IL-17, IL-4, IL-13 and IL-10 in patients and controls. The activities of gelatinases (MMP-9 and -2) were significantly higher in CDK than in controls (p < 0.001), while TIMP-1 levels were significantly lower in patients (p < 0.05). The concentration of MMP-8 was higher in controls, but levels of this collagenase-2 were 30 times higher, both in CDK and controls, with respect to MMP-8 values of individuals inhabiting an urban area. By IHC we observed reactivity for MMP-9 in most epithelial cells only in CDK corneas. Conclussion. We demonstrated a key role of the axis pro-inflammatory cytokines ­ gelatinases in the development of CDK. High levels of IL-1ß and IL-8 in tears of patients facilitate the production of MMP-8 and gelatinases, and the effects of these molecules are exacerbated because patients have low levels of their natural inhibitors (TIMP-1). Since MMP-9 besides degrading extracellular matrix components, catalyzes the post translational activation of IL-1ß, the inflammatory process is fuelled. These results are the first to explain immunological mechanisms involved in the pathogenesis of the QCE and provide new alternatives for the development of preventive therapies using inhibitors of IL-1ß and / or gelatinases.(AU)


Subject(s)
Humans , Adult , Ascorbic Acid Deficiency , Cytokines , Corneal Diseases , Immunologic Factors/deficiency
12.
G Ital Nefrol ; 27(6): 668-73, 2010.
Article in Italian | MEDLINE | ID: mdl-21132650

ABSTRACT

Immunotactoid glomerulopathy is a clinicopathological entity characterized by extracellular deposition of microtubular substructures, which are negative for the usual staining that identifies amyloid within the mesangium and capillary walls of renal glomeruli. Despite ongoing debate in the nephrological community, it is kept distinct from fibrillary glomerulonephritis on the basis of the size and arrangement of the microtubules and microfibrils. It is clinically characterized by the presence of glomerular proteinuria in the nephrotic range, microscopic hematuria and hypertension, and is often associated with hypocomplementemia, monoclonal gammopathy, and lymphoprolipherative disorders. A 47-year-old woman was referred to our unit for evaluation of proteinuria associated with nephrotic syndrome. Laboratory findings revealed a serum M component and hypocomplementemia. Renal biopsy yielded three fragments for optical microscopy, immunofluorescence, and electron microscopy; Congo red staining was used. Renal histology showed a morphological pattern of membranoproliferative glomerulonephritis. Immunofluorescence showed IgG deposits with monoclonal kappa light chain restriction as well as C3 and C1q deposits. Electron microscopy revealed the presence within the mesangium of microtubules measuring >35 nm that were focally parallel oriented. The final diagnosis was nephrotic syndrome caused by immunotactoid glomerulopathy. The clinical diagnosis of immunotactoid glomerulopathy is based on pathological, clinical and hematological features and requires the exclusion of other diseases that are associated with organized glomerular deposits. We discuss the diagnostic options offered by the clinical and morphological elements of this case; the use of electron microscopy is emphasized, especially when a renal syndrome is associated with paraproteinemia.


Subject(s)
Glomerulonephritis, Membranoproliferative/diagnosis , Nephrotic Syndrome/diagnosis , Complement C3/deficiency , Diagnosis, Differential , Disease Progression , Female , Glomerulonephritis, Membranoproliferative/complications , Glomerulonephritis, Membranoproliferative/drug therapy , Glomerulonephritis, Membranoproliferative/immunology , Glucocorticoids/therapeutic use , Humans , Immunologic Factors/deficiency , Middle Aged , Nephrotic Syndrome/drug therapy , Nephrotic Syndrome/etiology , Nephrotic Syndrome/immunology , Prednisone/therapeutic use , Proteinuria/etiology , Treatment Outcome
13.
Biochem Pharmacol ; 76(6): 726-37, 2008 Sep 15.
Article in English | MEDLINE | ID: mdl-18656454

ABSTRACT

Cannabidiol (CBD) is a cannabinoid compound derived from Cannabis Sativa that does not possess high affinity for either the CB1 or CB2 cannabinoid receptors. Similar to other cannabinoids, we demonstrated previously that CBD suppressed interleukin-2 (IL-2) production from phorbol ester plus calcium ionophore (PMA/Io)-activated murine splenocytes. Thus, the focus of the present studies was to further characterize the effect of CBD on immune function. CBD also suppressed IL-2 and interferon-gamma (IFN-gamma) mRNA expression, proliferation, and cell surface expression of the IL-2 receptor alpha chain, CD25. While all of these observations support the fact that CBD suppresses T cell function, we now demonstrate that CBD suppressed IL-2 and IFN-gamma production in purified splenic T cells. CBD also suppressed activator protein-1 (AP-1) and nuclear factor of activated T cells (NFAT) transcriptional activity, which are critical regulators of IL-2 and IFN-gamma. Furthermore, CBD suppressed the T cell-dependent anti-sheep red blood cell immunoglobulin M antibody forming cell (anti-sRBC IgM AFC) response. Finally, using splenocytes derived from CB1(-/-)/CB2(-/-) mice, it was determined that suppression of IL-2 and IFN-gamma and suppression of the in vitro anti-sRBC IgM AFC response occurred independently of both CB1 and CB2. However, the magnitude of the immune response to sRBC was significantly depressed in CB1(-/-)/CB2(-/-) mice. Taken together, these data suggest that CBD suppresses T cell function and that CB1 and/or CB2 play a critical role in the magnitude of the in vitro anti-sRBC IgM AFC response.


Subject(s)
Cannabidiol/pharmacology , Immunologic Factors/pharmacology , NFATC Transcription Factors/antagonists & inhibitors , Animals , Cannabidiol/metabolism , Cells, Cultured , Dose-Response Relationship, Drug , Female , Humans , Immunoglobulin M/biosynthesis , Immunologic Factors/deficiency , Interferon-gamma/immunology , Interleukin-2/immunology , Jurkat Cells , Mice , Mice, Inbred C57BL , Mice, Knockout , NFATC Transcription Factors/physiology , Spleen/cytology , Spleen/drug effects , Spleen/physiology , T-Lymphocytes/drug effects , T-Lymphocytes/physiology
14.
Hum Biol ; 80(1): 83-93, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18505047

ABSTRACT

Five types of known mutations within the C1q gene [located at C1qA-Gln186 (C >T), C1qB-Gly15 (G >A), C1qB-Arg150 (C >T), C1qC-Gly6 (G >A), and C1qC-Arg41 (C >T)] and two SNPs located at C1qA-Gly70 (G/A) and C1qC-Pro14 (T/C) were screened in a multiracial Malaysian population. One hundred thirty patients with systemic lupus erythematosus (SLE) and 130 matched healthy control subjects were genotyped using PCR-RFLP methods. We found no occurrence of the five types of mutations in either the homozygous or heterozygous form among the 260 samples studied. Statistical analysis also revealed that there were no significant associations observed in the genotype distributions and allele frequencies among the patients with SLE and healthy control subjects with both C1qA-Gly70 (G/A) and C1qC-Pro14 (T/C) SNPs. Overall, C1q deficiency was not proven as a primary causative genetic predisposition factor for SLE in the Malaysian population.


Subject(s)
Complement C1q/genetics , Genotype , Immunologic Factors/genetics , Lupus Erythematosus, Systemic/genetics , Mutation , Polymorphism, Single Nucleotide , Case-Control Studies , Complement C1q/deficiency , Complement C1q/isolation & purification , Humans , Immunologic Factors/deficiency , Immunologic Factors/isolation & purification , Lupus Erythematosus, Systemic/blood , Lupus Erythematosus, Systemic/immunology , Malaysia , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length
15.
J Immunol ; 179(3): 1634-47, 2007 Aug 01.
Article in English | MEDLINE | ID: mdl-17641030

ABSTRACT

1,25-Dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) can modulate immune responses, but whether it directly affects B cell function is unknown. Patients with systemic lupus erythematosus, especially those with antinuclear Abs and increased disease activity, had decreased 1,25(OH)(2)D(3) levels, suggesting that vitamin D might play a role in regulating autoantibody production. To address this, we examined the effects of 1,25(OH)(2)D(3) on B cell responses and found that it inhibited the ongoing proliferation of activated B cells and induced their apoptosis, whereas initial cell division was unimpeded. The generation of plasma cells and postswitch memory B cells was significantly inhibited by 1,25(OH)(2)D(3), although the up-regulation of genetic programs involved in B cell differentiation was only modestly affected. B cells expressed mRNAs for proteins involved in vitamin D activity, including 1 alpha-hydroxylase, 24-hydroxylase, and the vitamin D receptor, each of which was regulated by 1,25(OH)(2)D(3) and/or activation. Importantly, 1,25(OH)(2)D(3) up-regulated the expression of p27, but not of p18 and p21, which may be important in regulating the proliferation of activated B cells and their subsequent differentiation. These results indicate that 1,25(OH)(2)D(3) may play an important role in the maintenance of B cell homeostasis and that the correction of vitamin D deficiency may be useful in the treatment of B cell-mediated autoimmune disorders.


Subject(s)
B-Lymphocytes/cytology , B-Lymphocytes/drug effects , Calcitriol/physiology , Cell Differentiation/drug effects , Cell Differentiation/immunology , Immunologic Factors/physiology , ADP-ribosyl Cyclase 1/biosynthesis , Adolescent , Adult , Aged , Apoptosis/drug effects , Apoptosis/genetics , Apoptosis/immunology , B-Lymphocytes/enzymology , B-Lymphocytes/immunology , Calcitriol/deficiency , Calcitriol/pharmacology , Cell Differentiation/genetics , Cells, Cultured , Down-Regulation/drug effects , Down-Regulation/genetics , Down-Regulation/immunology , Female , Gene Expression Regulation/drug effects , Growth Inhibitors/genetics , Growth Inhibitors/physiology , Humans , Immunologic Factors/deficiency , Immunologic Factors/pharmacology , Lupus Erythematosus, Systemic/drug therapy , Lupus Erythematosus, Systemic/immunology , Lupus Erythematosus, Systemic/pathology , Lymphocyte Activation/drug effects , Male , Middle Aged , Plasma Cells/drug effects , Plasma Cells/pathology , Receptors, Calcitriol/biosynthesis , Receptors, Calcitriol/genetics , Steroid Hydroxylases/biosynthesis , Steroid Hydroxylases/genetics , Vitamin D/analogs & derivatives , Vitamin D/antagonists & inhibitors , Vitamin D/blood , Vitamin D3 24-Hydroxylase
16.
Pediatr. aten. prim ; 8(31): 491-504, jul.-sept. 2006.
Article in Spanish | IBECS | ID: ibc-140435

ABSTRACT

En los últimos años se han producido novedades en el tratamiento de la dermatitis atópica (DA) con la aparición de dos nuevos fármacos inhibidores de la calcineurina: tacrolimus (T) y pimecrolimus (P). Diversos ensayos clínicos aleatorizados controlados con placebo han demostrado que T y P son eficaces para el control de la DA. Sin embargo, la comunicación de potenciales efectos adversos graves a largo plazo (neoplasias), el elevado coste de ambos medicamentos y la escasez de estudios que los comparen con el tratamiento tópico habitual (corticoides de distinta potencia) hacen pertinente la realización de una búsqueda bibliográfica para responder a la pregunta: en niños y adolescentes con DA, ¿el tratamiento con inmunomoduladores tópicos es más eficaz, seguro y/o eficiente que el tratamiento con corticoides? Se realizó una búsqueda bibliográfica en TRIP Database y Pub- Med y se recuperaron tres documentos relevantes: dos revisiones sistemáticas y un informe de evaluación de tecnologías sanitarias. De su valoración crítica se concluye que P y T no deben considerarse fármacos de primera elección para el tratamiento de la DA y no pueden ser utilizados en ningún caso en menores de dos años. En presencia de efectos adversos o ?corticofobia? familiar, se podrían plantear como segunda línea de tratamiento en la DA moderada-grave, tras la oportuna información de beneficios-perjuicios-costes: en este sentido, los estudios actuales apoyan el uso preferente de T sobre P. Cuando esté indicado su uso, debe realizarse durante períodos cortos. El tratamiento de primera elección en los brotes de DA siguen siendo los corticoides tópicos (AU)


Some new items have turned up in atopic dermatitis (DA) treatment during recent years as two new calcioneurin-inhibitor drugs have appeared: tacrolimus (T) and pimecrolimus (P). Several randomized placebo-controlled trials have proved that T and P are effective in the treatment of DA. Nevertheless, the communication of potential severe long-time side effects (cancer), the high cost of both drugs and the need of studies comparing them with conventional treatment (steroids of different strength) make it appropriate to make a bibliographic search to be able to answer to the question: in children and adolescents with DA, topical immunomodulator treatment is more effective, save and/or efficient than steroid treatment? A bibliographic search in TRIP Database and Pub-Med was undertaken and three relevant documents were retrieved: two systematic reviews and one report on evaluation of sanitary technologies. After their critical appraisal we conclude that P and T should not be considered first line drugs in DA treatment and, should never be used in any case in children under two years of age. If corticoid side effects are present or there exists familial “corticophobia”, they could be used as second line drugs in moderate-severe DA, after informing parents on benefits-risk-cost: current studies support the use of T rather than P. When prescribed they should be used for short periods of time. First line treatment in DA exacerbations is still topical steroids (AU)


Subject(s)
Adolescent , Child , Infant, Newborn , Humans , Immunologic Factors/administration & dosage , Immunologic Factors/deficiency , Anti-Infective Agents, Local/metabolism , Anti-Infective Agents, Local/pharmacology , Dermatitis, Atopic/complications , Dermatitis, Atopic/pathology , Pharmaceutical Preparations , Pharmaceutical Preparations/metabolism , Clinical Trials as Topic/methods , Clinical Trials as Topic/psychology , Immunologic Factors/genetics , Immunologic Factors/metabolism , Anti-Infective Agents, Local/administration & dosage , Anti-Infective Agents, Local , Dermatitis, Atopic/genetics , Dermatitis, Atopic/metabolism , Pharmaceutical Preparations/administration & dosage , Pharmaceutical Preparations/blood , Clinical Trials as Topic/instrumentation , Clinical Trials as Topic
18.
J. bras. med ; 76(1/2): 19-21, fev. 1999.
Article in Portuguese | LILACS | ID: lil-344315

ABSTRACT

Os autores revisam evidências que sugerem a participação de infecções virais na etiopatogênese da artrite reumatóide juvenil (ARJ), bem como o papel de alterações imunológicas e mediadores inflamatórios reguladores da resposta imune (citocinas) no desencadeamento do processo inflamatório intra-articular


Subject(s)
Adolescent , Arthritis, Rheumatoid , Virus Diseases , Cytokines , Immunologic Factors/deficiency , Risk Factors
SELECTION OF CITATIONS
SEARCH DETAIL
...