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1.
J Laryngol Otol ; 131(7): 614-619, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28502258

ABSTRACT

BACKGROUND: Eustachian tube dysfunction is a poorly defined condition associated with various symptoms and it can predispose to middle-ear disease. Balloon dilation Eustachian tuboplasty has been proposed as a treatment for Eustachian tube dysfunction. OBJECTIVE: To evaluate the subjective and objective outcomes of balloon dilation Eustachian tuboplasty in patients with recurrent, previously treated chronic Eustachian tube dysfunction. METHODS: The study was conducted on 11 patients (13 ears) who had undergone previous unsuccessful medical and surgical treatment. Tympanometry was the primary outcome measure. Secondary outcome measures included pure tone audiogram assessment and seven-item Eustachian Tube Dysfunction Questionnaire score. RESULTS: Balloon dilation Eustachian tuboplasty resulted in significant improvements in 11 patients' subjective but not objective outcome measures. CONCLUSION: The objective abnormality and subjective symptoms in Eustachian tube dysfunction may represent two distinct pathological processes, which may nevertheless influence and exacerbate each other.


Subject(s)
Dilatation/methods , Ear Diseases/therapy , Eustachian Tube , Adult , Catheterization/methods , Ear Diseases/diagnosis , Endoscopy , Female , Humans , Male , Middle Aged , Patient Satisfaction , Treatment Outcome
2.
J Med Life ; 6(3): 244-8, 2013 Sep 15.
Article in English | MEDLINE | ID: mdl-24155782

ABSTRACT

Respiratory diseases are responsible for a significant number of deaths and considerable suffering in humans. Accumulating evidence suggests that oral disorders, particularly periodontal disease, may influence the course of respiratory infections like bacterial pneumonia and chronic obstructive pulmonary disease (COPD). Oral periodontopathic bacteria can be aspirated into the lung causing aspiration pneumonia. The teeth may also serve as a reservoir for respiratory pathogen colonization and subsequent nosocomial pneumonia. The overreaction of the inflammatory process that leads to the destruction of the connective tissue is present in both periodontal disease and emphysema. This overreaction may explain the association between periodontal disease and chronic obstructive pulmonary disease. The mechanisms of infection could be the aspiration into the lung of oral pathogens capable of causing pneumonia, colonization of dental plaque by respiratory pathogens followed by aspiration, or facilitation of colonization of the upper airway by pulmonary pathogens by periodontal pathogens. The present article briefly reviews the epidemiologic evidence & role of periodontopathogens in causing respiratory infections.


Subject(s)
Periodontal Diseases/complications , Periodontal Diseases/microbiology , Respiratory Tract Diseases/etiology , Respiratory Tract Diseases/microbiology , Cytokines/metabolism , Humans , Respiratory Aspiration/complications , Respiratory Aspiration/microbiology , Respiratory Mucosa/microbiology , Respiratory Mucosa/pathology , Risk Factors
3.
Clin Exp Immunol ; 172(2): 217-27, 2013 May.
Article in English | MEDLINE | ID: mdl-23574318

ABSTRACT

Nuclear factor (NF)-κB is a transcription factor implicated in the pathogenesis of autoimmune disorders such as rheumatoid arthritis (RA). Here we have examined the effect of intra-articular administration of the IKK inhibitor, NEMO-binding domain peptide (NBD), on the severity of collagen-induced arthritis (CIA). NBD peptides were injected intra-articularly into the knee joints of DBA/1J mice after the onset of disease. Collagen-injected mice given a scrambled peptide served as controls. Arthritis severity was determined by visual examination of paws. Intra-articular NBD injection reduced the arthritis score and ameliorated morphological signs of bone destruction compared to the controls. Serum levels of type-II collagen-specific immunoglobulin (Ig)G2a antibodies were lower in NBD-treated mice versus the control mice, whereas the levels of type-II collagen-specific IgG1 antibodies were increased by NBD treatment. NBD treatment diminished the proinflammatory cytokines interleukin (IL)-17 and interferon (IFN)-γ in serum, but increased the regulatory cytokine IL-10. NBD-treated CIA mice exhibited significantly higher percentages and numbers of forkhead box protein 3 (FoxP3(+)) CD4(+) CD25(+) regulatory T cells than controls. Immunofluorescence analysis of NBD-treated mice revealed that FoxP3 and Ym1, a marker of alternatively activated macrophages, were juxtaposed to each other within draining inguinal lymph nodes. Intra-articular administration of NBD peptide is effective as an experimental therapy in a murine model of RA. Nevertheless, the intra-articular treatment modality is still associated with systemic effects on the immune system.


Subject(s)
Arthritis, Experimental/drug therapy , Arthritis, Experimental/immunology , Macrophages/immunology , NF-kappa B/antagonists & inhibitors , T-Lymphocytes, Regulatory/immunology , Animals , Arthritis, Experimental/metabolism , Autoimmunity , CD4 Antigens/biosynthesis , Collagen , Forkhead Transcription Factors/biosynthesis , Immunoglobulin G/immunology , Interferon-gamma/blood , Interleukin-10/blood , Interleukin-17/biosynthesis , Interleukin-2 Receptor alpha Subunit/biosynthesis , Lectins , Lymphocyte Activation , Macrophage Activation , Macrophages/metabolism , Male , Mice , Mice, Inbred DBA , Peptides/administration & dosage , Peptides/pharmacology , T-Lymphocytes, Regulatory/metabolism , beta-N-Acetylhexosaminidases
4.
J Contemp Dent Pract ; 13(4): 571-3, 2012 Jul 01.
Article in English | MEDLINE | ID: mdl-23151712

ABSTRACT

UNLABELLED: Fluorosis can cause enamel degeneration to varying extent depending on the fluoride levels prevalent in that particular area. It can range from slight mottling of enamel to severe degeneration leading to demineralization and resultant discoloration. In the latter case, treatment options are limited to bonding of the outer surface of teeth either with composite or porcelain. CLINICAL SIGNIFICANCE: Porcelain laminates offer an excellent solution to enhance esthetics in a patient with fluorosis as it combines the advantage of being highly esthetic along with being conservative in its penetration to enamel.


Subject(s)
Dental Porcelain/therapeutic use , Dental Veneers , Fluorosis, Dental/therapy , Humans , Male , Tooth Preparation, Prosthodontic , Young Adult
5.
J Contemp Dent Pract ; 13(1): 80-4, 2012 Jan 01.
Article in English | MEDLINE | ID: mdl-22430699

ABSTRACT

The present study was undertaken to assess the skeletal craniofacial asymmetry in South Indian population by a posteroanterior cephalometric radiographic method. The skeletal craniofacial structures on one side of the face were compared with that of the other, by drawing various triangles representing different craniofacial regions. The sample consisted of 60 subjects (30 males and 30 females) aged between 18 to 25 years, who were mainly dental college students from South India. Overall 52 X-rays were obtained, with four errors each in the male and the female groups. The results revealed that the total facial structures in the South Indian population were larger on the left side (statistically insignificant). The cranial base area exhibited a greater degree of asymmetry than any other component area of the face, which might be due to the inaccuracy at the condylar point.


Subject(s)
Cephalometry/methods , Facial Asymmetry/diagnosis , Facial Bones/pathology , Skull/pathology , Adolescent , Adult , Chin/pathology , Dental Occlusion, Centric , Female , Humans , Incisor/pathology , India , Male , Mandible/pathology , Mandibular Condyle/pathology , Mastoid/pathology , Molar/pathology , Nasal Bone/pathology , Sella Turcica/pathology , Young Adult , Zygoma/pathology
6.
J Dent Res ; 91(2): 142-9, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21876032

ABSTRACT

Cigarette smoke (CS) causes considerable morbidity and mortality by inducing cancer, chronic lung and vascular diseases, and oral disease. Despite the well-recognized risks associated with smoking, the habit remains unacceptably prevalent. Several toxins present in CS have immunomodulatory effects. CS also contains trace amounts of microbial cell components, including bacterial lipopolysaccharide. These and other CS constituents induce chronic inflammation at mucosal surfaces and modify host responses to exogenous antigens. The effects of CS on immunity are far-reaching and complex; both pro-inflammatory and suppressive effects may be induced. The net effect of CS on immunity depends on many variables, including the dose and type of tobacco, the route and chronicity of exposure, and the presence of other factors at the time of immune cell stimulation, such as Toll receptor ligands or other inflammatory mediators. CS impairs innate defenses against pathogens, modulates antigen presentation, and promotes autoimmunity. CS also impairs immunity in the oral cavity and promotes gingival and periodontal disease and oral cancer. The recognition of specific mechanisms by which CS affects host immunity is an important step toward elucidating mechanisms of tobacco-induced disease and may identify novel therapeutic approaches for the management of diseases that afflict smokers.


Subject(s)
Smoking/immunology , Antigen Presentation/immunology , Autoimmunity/immunology , Complex Mixtures/immunology , Humans , Immunity, Mucosal/immunology , Immunologic Factors/immunology , Immunosuppressive Agents/immunology , Inflammation/immunology , Inflammation Mediators/immunology , Mouth Diseases/immunology , Mouth Neoplasms/immunology , Periodontal Diseases/immunology , Toxins, Biological/immunology
7.
Child Care Health Dev ; 31(6): 703-6, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16207228

ABSTRACT

BACKGROUND: We have previously reported the developmental gains achieved, after introducing a simple programme of structured play to stimulate children in an orphanage. It was envisaged that the caregivers could continue the programme. However, the enthusiasm of the caregivers waned over the year the programme was entrusted to them. After 1 year, a full time play therapist was recruited to rejuvenate the play programme. METHODS: Children's development was assessed using the Indian adaptation of the Bayley Scales of Infant Development. The first assessment was done when the play therapist joined. Subsequently, three-monthly assessments were done and the scores achieved were recorded. RESULTS: The initial mean motor and mental scores, when the play therapist joined, were 66.14 and 56.95, respectively (similar to the pre-intervention scores of the pilot study reported in an earlier paper). The scores improved to 81.84 and 78.25 within 3 months of restarting the play programme. CONCLUSION: The schedule of the 'Not by Bread Alone' project can accelerate the motor and mental development of children in orphanages. However, it requires a highly motivated and dedicated person to sustain this programme over long periods.


Subject(s)
Child Development , Orphanages , Play Therapy/methods , Attitude to Health , Child, Institutionalized/psychology , Child, Preschool , Humans , Infant , Intelligence , Motor Skills/physiology
8.
Cell Mol Biol (Noisy-le-grand) ; 49(2): 193-207, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12887102

ABSTRACT

Autoantibodies directed against variable domain epitopes of the alpha/beta T cell receptor (TCR) occur in sera of man, mouse and other vertebrates. Here, we focus upon autoantibodies expressed in human rheumatoid arthritis (RA) and systemic erythematosus (SLE) with parallel studies involving collagen induced arthritis (CIA) in mice transgenic for human HLA-DR conferring resistance or susceptibility to autoimmune disease. We report specificity characterization of polyclonal and monoclonal IgM and IgG autoantibodies from SLE and for IgM monoclonal autoantibodies of RA patients. The data suggests that autoantibodies directed against "public" idiotopes present in the first complementarity determining region (CDR1) and the third framework (FR3) of the Vbeta gene products are generated in response to over-production of autodestructive T cells bearing particular Vbeta gene products and function to modulate (downregulate) the expression of these T cells. Since antibodies of these specificities are present in polyclonal IgG immunoglobulin (IVIG) preparations used for therapeutic purposes, the immunomodulatory effects of antibodies directed against TCR variable domains may account, at least in part, for the efficacy of IVIG preparations in therapy of autoimmune diseases and in the prevention of graft versus host reactions.


Subject(s)
Autoantibodies/immunology , Immunoglobulin Idiotypes/immunology , Receptors, Antigen, T-Cell/immunology , Animals , Arthritis, Rheumatoid/immunology , Humans , Interleukin-2/metabolism , Lupus Erythematosus, Systemic/immunology , Mice , T-Lymphocytes
9.
Child Care Health Dev ; 28(1): 95-100, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11856192

ABSTRACT

BACKGROUND AND OBJECTIVES: In developing countries, caring for the large number of babies in orphanages is very hard work. Whereas the physical needs of most of the children are met, play often gets neglected. Studies have repeatedly shown that babies in such institutionalized settings suffer from severe psychomotor retardation. The aim of this project was to develop an intervention programme of structured play. We hypothesized that such an intervention would result in acceleration of psychosocial development in otherwise healthy institutionalized children. DESIGN: Prospective longitudinal. SETTING: Mother Teresa's Orphanage, run by Missionaries of Charity. SUBJECT AND METHODS: All 30 children in the orphanage aged 6 months-2.5 years, were assessed for their Motor, Mental and Social Quotients, using the Indian adaptation of Bailey's Scale of Infant Development(DASII) and the Vineland's Social Maturity Scale. A structured 'Regime of Play' was then built into the routine of the orphanage. A repeat developmental assessment was performed at the end of 3 months to assess the impact. RESULTS: Out of the original cohort of 30, 19 children were available for post-intervention assessments. The remainder were adopted before their assessments. Their mean Motor Quotient rose from 63.7 to 81.7, mean Mental Quotient rose from 65.8 to 89.6 and the mean Social Quotient rose from 61.9 to 91.3, a gain of 18, 23 and 30 points respectively (p < 0.0001). There was also an overall change in the environment of the orphanage. Children became more active, playful, responsive and independent. Contrary to what caretakers assumed, their workload actually decreased. The responsiveness in the children awakened as a result of play, acted as a positive feedback for caretakers to continue the play sessions. CONCLUSIONS: This study shows that short daily sessions of play can significantly improve the development of children in such institutions. It is vital to remember that children grow 'Not by Bread Alone'.


Subject(s)
Child Development , Child, Institutionalized/psychology , Foster Home Care , Play Therapy , Child, Preschool , Cohort Studies , Developing Countries , Humans , India , Infant , Outcome Assessment, Health Care
12.
Arthritis Res ; 2(3): 205-7, 2000.
Article in English | MEDLINE | ID: mdl-11094430

ABSTRACT

Human leucocyte antigen (HLA) class II molecules have been shown to be associated with predisposition to rheumatoid arthritis (RA). We generated HLA-DR and DQ transgenic mice that lacked endogenous class II molecules to study the interaction between the DR and DQ molecules and define the immunologic mechanisms in rheumatoid arthritis. Using collagen-induced arthritis (CIA) as an experimental model for inflammatory polyarthritis, we show that both DQ and DR are involved in predisposition or resistance to arthritis. Our studies suggest that polymorphism in DQB1 genes may determine predisposition to RA while the DRB1 polymorphism may dictate severity/protection of the disease. These mice provide powerful tools to develop immunotherapeutic protocols.


Subject(s)
Arthritis, Rheumatoid/immunology , Arthritis, Rheumatoid/physiopathology , Histocompatibility Antigens Class II/genetics , Histocompatibility Antigens Class II/immunology , Animals , Disease Models, Animal , Humans , Mice , Mice, Knockout
14.
Hum Immunol ; 61(12): 1383-9, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11163096

ABSTRACT

On the basis of our extensive studies on collagen induced arthritis in HLA class II transgenic mice, we proposed a hypothesis to explain role of shared epitope in rheumatoid arthritis (RA) association. According to our hypothesis, complementation between both DQ and DR molecules is required for susceptibility or protection from disease. While certain DQ alleles predispose individuals to RA, DRB1 molecule can modulate disease by shaping T-cell repertoire in the thymus by providing self-peptides and presented by DQ molecules. Using A beta o.DQ8 transgenic mice, we tested ability of peptides derived from HV3 of DR molecules, implicated in RA positively or negatively, to activate T cells. While the peptides derived from RA susceptible DR molecule were poor binders and poor in activating T cells, the peptides derived from RA resistant DR molecules were high affinity binders and efficient T-cell activators. Our experiments suggest that high affinity DR peptides could induce tolerance to autoimmunity while the low affinity peptides could be permissive to autoimmunity. Using peptide from DRB1*0402 molecule, known to be associated with resistance to RA, prior to induction of collagen induced arthritis prevents the onset of disease. Thus, self-peptides derived from HLA molecules could potentially generate tolerance or autoimmunity depending on their binding affinity with HLA molecules.


Subject(s)
Arthritis, Rheumatoid/genetics , Arthritis, Rheumatoid/immunology , Autoimmune Diseases/genetics , Immune Tolerance/genetics , Animals , Arthritis, Rheumatoid/therapy , Autoimmune Diseases/therapy , Collagen/administration & dosage , Collagen/immunology , Genetic Predisposition to Disease , HLA-DQ Antigens/biosynthesis , HLA-DQ Antigens/genetics , HLA-DR Antigens/genetics , HLA-DRB1 Chains , Humans , Mice , Mice, Transgenic , Peptide Fragments/chemical synthesis , Peptide Fragments/immunology , Peptide Fragments/therapeutic use , Sequence Homology, Amino Acid , T-Lymphocytes/immunology
15.
Hum Immunol ; 60(9): 816-25, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10527388

ABSTRACT

We generated transgenic mice with DRB1*0401 gene with mutation in the beta2 domain (aa 110 and 139) for better interaction with mCD4. The DR4 transgene was introduced into H2-Aq (B10RQB3) and H2-Af (B10RFB3) to examine the role of DR4 in collagen arthritis. The HLA-DR molecules in these mice were found to be functional on the basis of their positive/negative selection of the Vbeta T cell repertoire. H2-Aq mice are resistant to porcine CII-induced arthritis. The RQB3/DR4 mice (H2Aq/DR4) developed severe collagen induced arthritis (CIA) when immunized with Porcine type II collagen while the negative littermates were resistant. RQB3.DR4 mice were also highly susceptible to CIA induced by Human CII while negative littermates got only mild disease. However, RFB3/DR4 mice (H2Af/ DR4) did not get CIA with any type II collagen. Therefore, the DR4 gene in the context of H2-Aq predisposes to severe arthritis but not in the context of H2-Af. Antibodies to renatured cyanogen bromide (CB) cleaved fragments of PII in RQB3/DR4 mice and negative littermates suggest that the presence of DR4 does not result in any differences in specificity of antibody response to CB fragments. These results indicate that a specific gene complementation occurring between DR4 and H2.Aq but not DR4 and H2Af promotes the induction of arthritis with PII and HII in these mice. A similar interaction may be involved between DR and DQ molecules in human RA.


Subject(s)
Arthritis, Rheumatoid/immunology , H-2 Antigens/immunology , HLA-DR Antigens/immunology , HLA-DR4 Antigen/immunology , Animals , Arthritis, Experimental/immunology , Arthritis, Rheumatoid/chemically induced , Collagen/immunology , Disease Models, Animal , Drug Resistance , Gene Expression , HLA-DR Antigens/biosynthesis , HLA-DR Antigens/genetics , HLA-DR4 Antigen/biosynthesis , HLA-DR4 Antigen/genetics , HLA-DRB1 Chains , Humans , Interferon-gamma/immunology , Mice , Mice, Transgenic , Receptors, Antigen, T-Cell, alpha-beta/biosynthesis , Swine
16.
Immunol Rev ; 169: 67-79, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10450509

ABSTRACT

Predisposition to develop various autoimmune disorders has been associated with certain HLA class II molecules but there is a lack of information on the pathophysiological role of HLA genes in conferring susceptibility. Various experimental animal models of autoimmune disease have been studied to address the role of immune response genes. To study the interactions involved between class II molecules (DQ and DR) and define the immunologic mechanisms in various diseases, we generated HLA-DR and DQ transgenic mice that lacked endogenous class II molecules. The HLA molecules in these mice are expressed on the cell surface and can positively select CD4+ T cells expressing various V beta T-cell receptors (TCR). A peripheral tolerance is maintained to transgenic HLA molecules thus indicating that these molecules act as self. Mouse co-stimulatory and accessory molecules can interact with the HLA-peptide-TCR complex leading to efficient T-cell activation. In this review, we describe immunogenetic models for human diseases using these transgenic mice. Our studies show that HLA class II transgene-restricted T cells recognize the immunodominant antigens and peptide epitopes, similar to HLA class II-restricted human T cells. Thus these mice provide powerful tools to understand the role of HLA class II molecules in predisposition and onset of human diseases and to develop immunotherapy and vaccines.


Subject(s)
Autoimmune Diseases/genetics , Autoimmune Diseases/immunology , Genes, MHC Class II , HLA-DQ Antigens/genetics , HLA-DR Antigens/genetics , Amino Acid Sequence , Animals , Arthritis, Rheumatoid/genetics , Arthritis, Rheumatoid/immunology , Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 1/immunology , Disease Models, Animal , Humans , Hypersensitivity/genetics , Hypersensitivity/immunology , Mice , Mice, Transgenic , Multiple Sclerosis/genetics , Multiple Sclerosis/immunology , Myasthenia Gravis/genetics , Myasthenia Gravis/immunology , Polychondritis, Relapsing/genetics , Polychondritis, Relapsing/immunology , Selection, Genetic , Thyroiditis, Autoimmune/genetics , Thyroiditis, Autoimmune/immunology , Vaccines/genetics , Vaccines/immunology
17.
Biochim Biophys Acta ; 1433(1-2): 272-80, 1999 Aug 17.
Article in English | MEDLINE | ID: mdl-10446377

ABSTRACT

A non-specific acid phosphatase (APase) hydrolysing L-tyrosine-O-phosphate and 3'-AMP was purified to electrophoretic homogeneity from mature lentil seeds with apparent native molecular mass of 100 kDa and subunit molecular mass of 24 kDa. These activities appear to reside on the same protein which shows a single band in native and SDS-PAGE. The pH optimum is 5.5, while the K(m) (mM) and V(max) (micromoles/min/mg protein) for p-nitrophenyl phosphate (pNPP) are 0.7 and 9.2 and for L-tyrosine-O-phosphate 1.4 and 10.1, respectively, at 30 degrees C and for 3'-AMP, 2 and 4.4 at 37 degrees C. The protein also hydrolyses other phosphomonoesters to a lesser extent. L-Tyrosine-O-phosphate, 3'-AMP and pNPP hydrolysis is potently inhibited by micromolar orthovanadate and also to nearly the same extent by sodium fluoride, potassium tartrate and metal ions. Histidine and cysteine are likely to be involved in the catalysis. Thermal inactivation studies indicate that the active site conformations for pNPP and 3'-AMP hydrolytic activities are different. The enzyme shows the characteristics of the animal protein tyrosine phosphatase.


Subject(s)
Fabaceae/enzymology , Plants, Medicinal , Protein Tyrosine Phosphatases/chemistry , Adenosine Monophosphate/metabolism , Aniline Compounds/metabolism , Binding Sites , Chromatography, Liquid/methods , Cysteine/analysis , Electrophoresis, Polyacrylamide Gel , Enzyme Inhibitors/pharmacology , Histidine/analysis , Kinetics , Molecular Weight , Organophosphorus Compounds/metabolism , Protein Conformation , Protein Tyrosine Phosphatases/isolation & purification , Protein Tyrosine Phosphatases/metabolism , Seeds/enzymology , Substrate Specificity
18.
Biochem Biophys Res Commun ; 250(3): 629-34, 1998 Sep 29.
Article in English | MEDLINE | ID: mdl-9784397

ABSTRACT

A germination specific isozyme of acid phosphatase (EC 3.1.3.2) hydrolysing O-phospho-L-Tyrosine, pH optima 5.5 is induced in lentil seeds. When seeds at 0 h, 24 h and 36 h of germination are electrophorezed, native PAGE on specific enzyme staining shows several constitutive isozymes of acid phosphatases. At 48 h, an isozyme is induced which gradually decreases and then disappears at 108 h of germination. The short lived, induced isozyme is present in the embryo and seed-coat but not in the plumule and the radical. Induction of this isozyme is inhibited by cycloheximide and actinomycin-D and increased by plant growth regulators such as heteroauxin and gibbrellic acid treatment during germination. The induced isozyme is a single 30 kD polypeptide, with subunit molecular mass of 25 kD, shows activity for O-phospho-L-Tyrosine. It is strongly inhibited by vanadate (microM), molybdate, tungustate as also by iodoacetate, p-chloromercuribenzoate and diethylpyrocarbonate. This study shows for the first time that the germination induced low molecular weight Acid phosphatase is a Tyrosine phosphatase super family class IV enzyme, having a role in cellular differentiation and development during seed germination.


Subject(s)
Acid Phosphatase/metabolism , Fabaceae/enzymology , Isoenzymes/metabolism , Plants, Medicinal , Enzyme Induction , Protein Tyrosine Phosphatases/metabolism , Seeds/enzymology
19.
Int Immunol ; 10(10): 1449-57, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9796911

ABSTRACT

Mouse class II-deficient HLA-DQB1*0302, DQA1*0301 (DQ8) transgenic mice are susceptible to severe collagen-induced arthritis (CIA), an animal model for rheumatoid arthritis. To examine whether polymorphism at the DRB1 locus can modulate DQ-restricted arthritis, we generated double-transgenic (DR/DQ) mice. HLA-DRB1*1502 (DR2) and DRB1*0301 (DR3) were introduced separately into CIA susceptible DQ8.Abeta transgenic mice to generate DQ8/DR2.Abeta and DQ8/ DR3.AbetaO mice. The HLA-DR molecules in these mice were found to be functional on the basis of their positive/negative selection of the Vbeta T cell repertoire. Introduction of the DR2 gene led to a significant decrease in disease incidence in DQ8.Abeta mice, while the DR3 transgene had no effect. In vitro T cell proliferative responses against bovine Cll collagen in primed mice were higher in DQ8/DR3 mice compared with DQ8/DR2 mice. Cytokine analysis showed a Th2 profile in DQ8/DR2 mice, while DQ8/DR3 mice showed a Th1 profile. These results suggest that DRB1 polymorphism can modulate the disease.


Subject(s)
Arthritis/chemically induced , HLA-DQ Antigens/immunology , HLA-DR Antigens/genetics , Animals , Arthritis, Rheumatoid/chemically induced , Collagen/pharmacology , Disease Models, Animal , HLA-DQ Antigens/biosynthesis , HLA-DR Antigens/biosynthesis , HLA-DRB1 Chains , Immunoglobulin G/blood , Interleukin-4/biosynthesis , Lymphocyte Activation/drug effects , Lymphocytes/metabolism , Mice , Mice, Transgenic , Peptides/pharmacology , Polymorphism, Genetic/physiology , Receptors, Antigen, T-Cell, alpha-beta/biosynthesis , T-Lymphocytes/drug effects , T-Lymphocytes/immunology
20.
Proc Natl Acad Sci U S A ; 95(18): 10797-802, 1998 Sep 01.
Article in English | MEDLINE | ID: mdl-9724784

ABSTRACT

T helper 1 cells play a major role in protective immunity against mycobacterial pathogens. Since the antigen (Ag) specificity of CD4(+) human T cells is strongly controlled by HLA class II polymorphism, the immunogenic potential of candidate Ags needs to be defined in the context of HLA polymorphism. We have taken advantage of class II-deficient (Ab0) mice, transgenic for either HLA-DRA/B1*0301 (DR3) or HLA-DQB1*0302/DQA*0301 (DQ8) alleles. In these animals, all CD4(+) T cells are restricted by the HLA molecule. We reported previously that human DR3-restricted T cells frequently recognize heat shock protein (hsp)65 of Mycobacterium tuberculosis, and only a single hsp65 epitope, p1-20. DR3.Ab0 mice, immunized with bacillus Calmette-Guérin or hsp65, developed T cell responses to M. tuberculosis, and recognized the same hsp65 epitope, p1-20. Hsp65-immunized DQ8.Ab0 mice mounted a strong response to bacillus Calmette-Guérin but not to p1-20. Instead, we identified three new DQ8-restricted T cell epitopes in the regions 171-200, 311-340, and 411-440. DR3.Ab0 mice immunized with a second major M. tuberculosis protein, Ag85 (composed of 85A, 85B, and 85C), also developed T cell responses against only one determinant, 85B p51-70, that was identified in this study. Importantly, subsequent analysis of human T cell responses revealed that HLA-DR3+, Ag85-reactive individuals recognize exactly the same peptide epitope as DR3.Ab0 mice. Strikingly, both DR3-restricted T cell epitopes represent the best DR3-binding sequences in hsp65 and 85B, revealing a strong association between peptide-immunodominance and HLA binding affinity. Immunization of DR3.Ab0 with the immunodominant peptides p1-20 and p51-70 induced T cell reactivity to M. tuberculosis. Thus, for two different Ags, T cells from DR3.Ab0 mice and HLA-DR3+ humans recognize the same immunodominant determinants. Our data support the use of HLA-transgenic mice in identifying human T cell determinants for the design of new vaccines.


Subject(s)
Bacterial Proteins/immunology , Histocompatibility Antigens Class II/immunology , Mycobacterium tuberculosis/immunology , Amino Acid Sequence , Animals , BCG Vaccine , Epitopes/immunology , Humans , Mice , Mice, Transgenic , Molecular Sequence Data , T-Lymphocytes/immunology
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