March 2. 00. 9 | British Journal of Medical Practitioners. Authors. Article Citation and PDF Link. Abstract. Bacterial infections are associated with many autoimmune diseases involving chronic inflammation and demyelination. The possible mechanisms of bacterial involvement as aetiological agents or in the exacerbation of these diseases have been investigated intensively. G antigen of Rh blood group system is present either along with D and/or C positive red cells. Hence, [serologically anti-G presents with the similar picture as that. 9781434466518 1434466515 The Blue Poetry Book, Andrew Lang 9781434467294 1434467295 Lismoyle - An Experiment in Ireland, B.M. Croker 9781436871693 1436871697 Historic. This review focuses the role of bacterial infections in the pathogenesis of autoimmune, inflammatory and demyelinating diseases. Possible modes of pathogenic action of bacteria are discussed, viz. Toll- like receptor signalling, the interaction of heat shock proteins with the immune system, and the role of nitric oxide. An auto- regulatory loop might exist in the interaction of bacteria with the host and in pathogenic signal processing. These studies reveal potential therapeutic targets. Abbreviations: AQP4 Aquaporin- 4; AS ankylosing spondylitis; CSF cerebrospinal fluid; EAE autoimmune encephalomyelitis; GB Guillain- Barre syndrome; HLA human leukocyte antigens; HSP heat shock protein; IL interleukin; LPS lipopolysaccharides; MAM Mycoplasma arthritidis antigen; MHC [proteins encoded by] major histocompatibility gene complex; MS multiple sclerosis; NK natural killer cells; NMO neuromyelitis optica; NO nitric oxide; NOS nitirc oxide synthase; PCR polymerase chain reaction; RA rheumatoid arthritis; SLE systemic lupus erythematosus; TLR Toll- like receptors; TNF tumour necrosis factor. Introduction. Bacterial and viral infections are commonplace in a variety of autoimmune and chronic illnesses such as the chronic fatigue syndrome (myalgic encephalomyelitis), fibromyalgia syndrome, Gulf War illnesses and rheumatoid conditions. Much attention is focused at present on the role of bacteria and the possible mechanisms of their involvement in the pathogenesis of several diseases. The route of infection and penetration and the immune responses of the host can not only make any bacterial infection pathogenic but probably can also determine the aggressiveness of the disease and the chance for full recovery. Therefore the two basic elements addressed here are the association between bacterial infection and autoimmune disease and the involvement of the immune system in the disease process. Bacterial infections in rheumatoid conditions. Gmail is email that's intuitive, efficient, and useful. 15 GB of storage, less spam, and mobile access. References. Tracheal and tracheostomy tubes and airways. In: Al-Shaikh B and Stacey S eds. Essentials of anaesthetic equipment. 2 nd edition. Churchill Livingstone.A wide variety of bacterial infections have been associated with rheumatoid conditions. Rheumatic diseases might have a manifold aetiology with varying genetic susceptibility, but bacteria- related autoimmunity might be an important factor. Mycoplasma infection, e. M. pneumoniae, M. M. fermentans, has been strongly associated with RA (rheumatoid arthritis)5- 8. There is often systemic infection of more than one species. Windows Server 2003 Enterprise R2 Sp2 Full Iso Download here. Mycoplasma antigens induce both cell- mediated and humoral immune responses.Enhanced levels of antibodies against MAM (Mycoplasma arthritidis antigen) have been found in sera from RA patients in comparison with antibodies against Staphylococcal enterotoxins A and B. Also antibody titers were higher in RA serum than in systemic lupus erythematosus, ankylosing spondylitis, psoriatic arthritis, Reiter's syndrome, or healthy controls. The mycoplasma antigen MAM can activate T cells. MAM contains two domains, one of which can inhibit lymphocyte proliferation; the second domain, which contains concanavalin A motif- , is required for T cell activation. It can also up regulate natural killer cell activity. Furthermore, synovial tissues of RA patients contain T- cells, which bear the same T- cell receptors as used by MAM. The mitogen seems to be capable of initiating and exacerbating arthritic changes. MAM is a zinc- dependent antigen that binds to MHC class II molecules. Zinc induces MHC protein dimerisation required for MAM binding, MHC- induced cell- cell adhesion, and efficient T cell activation. As discussed in later sections, MAM can alter cytokine expression profiles and activate and modulate nitric oxide synthase (NOS) signalling pathways. Bacterial DNA isolated from rheumatoid arthritis (RA) and juvenile arthritis has included Haemophilus influenzae, Bordatella and Yersinia as possible infecting organisms. Lyme arthritis, which resembles rheumatoid synovial infiltration by Borrelia burgdorferi, has often been suggested to be an autoimmune condition. The B. burgdorferi surface protein A (Osp. A1. 61- 1. 75) is recognised by T- cells and HLA (human leukocyte antigen)- DR molecules that bind this T- cell epitope and to these events is attributed the development of autoimmunity following B. However, these decline with antibiotic therapy. Therefore, in spite of the perceived association, Drouin et al. Osp. A (1. 65- 1. The epitope Osp. A (1. Lyme disease. Serum reactivity against Osp.A is also found in RA patients.Our knowledge concerning the interaction of B.Ghosh et al. 1. 9 have suggested cytokeratin 1.Gavanescu et al. 2.It is not known if this cellular organelle is involved with autoimmunity in RA. here. B. burgdorferi seems to be able to induce inflammatory responses including secretion of cytokines and cellular responses of the T- helper cell- 1 (Th- 1) type. Beermann et al. 2. LV) from this bacterium and incorporated them into peripheral blood mononuclear cells. The resultant LV- T cells were predominantly the immune effector CD8+. Furthermore, these cells destroyed autologous T- cells carrying LV. These data do indeed support the existence of an autoimmune condition. Overall, a conservative conclusion would be that the molecular mimicry and autoimmunity thesis is yet to be fully tested. Proteus mirabilis has been implicated in the pathogenesis of RA2. OA)2. 7, 2. 8. Again, the HLA DRB1 alleles appear to be the major genetic susceptibility factors as postulated some years ago. Bacterial infection associated with other autoimmune conditions Bacterial infections have been identified in association with other autoimmune conditions besides RA. Members of the Enterobacteriaceae family are associated with autoimmune conditions such as Kawasaki syndrome and Graves disease. Demyelinating diseases have been a focus of active investigation in the past few years. Kollef et al. 3. 0 suggested that central and peripheral nerve demyelination might occur following M. Since then patients with the autoimmune condition SLE (systemic lupus erythematosus) have been investigated for mycoplasma infections. Early studies revealed differences between SLE patients and control subjects in respect of genitourinary mycoplasma infections. However, the deployment of more sensitive methods of detection has not supported these early claims. Runge et al. 3. 2, for instance, found no difference in the incidence of Ureaplasma urealyticum in SLE patients, and they discount the notion that this mycoplasma species has any role to play in the pathogenesis of SLE. Nonetheless, there should be no serious doubts that mycoplasma infection can lead to demyelination. The demyelinating neuropathy known as Guillain- Barre (GB) syndrome often has pathogenic association with bacterial infections. Campylobacter jejuni, Haemophilus influenzae and M pneumoniae have been implicated as possible causative agents of GB. C. jejuni is the major infecting organism here together with M. GB is associated with the presence of antibodies against galactocerebroside, which is a major component of myelin. Some bacterial LPS (lipopolysaccharides) apparently bear molecular similarity to the human gangliosides GM1, GM1b, GD1a, and Gal. NAc- GD1a of the motor axolemma and are said to be the target epitopes for antibodies occurring in the GB subtype acute motor axonal neuropathy. The antiganglioside antibodies cause axonal neuropathy.The host immune response to LPS moieties of the HB9.C. jejuni cross- reacts with human nerve gangliosides and induce GBS3. . Multiple sclerosis (MS) is a chronic inflammatory and demyelinating disease of the central nervous system. The pathogenesis of MS is possibly a consequence of autoimmune condition or infection by viral or bacterial agents. Both infections lead to the development of demyelinating plaques. Bacterial infections can evoke immune responses and induce demyelination. Infections of the brain parenchyma are sequestered from the immune system.
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