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1.
Rheumatology (Oxford) ; 43(8): 992-9, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15014199

RESUMO

OBJECTIVE: To evaluate the long-term safety of tacrolimus 3 mg/day in patients with rheumatoid arthritis (RA). METHODS: Patients with active RA who had discontinued all DMARDs for at least 2 weeks and had at least five tender/painful joints and three swollen joints, and required DMARD treatment in the opinion of the investigator, were enrolled into this open-label long-term safety trial. In addition, patients who had completed at least 3 months of treatment with tacrolimus 2 mg/day, tacrolimus 3 mg/day or placebo in a Phase III double-blind efficacy trial were allowed to roll over into this study. This latter group of patients did not have to fulfil any joint count requirements prior to entry into the long-term safety study, provided that no more than 14 days had elapsed between the end of their participation in the double-blind study and screening for the long-term safety study. All patients enrolled received tacrolimus 3 mg/day in addition to their current regimen of NSAIDs and corticosteroids. RESULTS: 896 patients received at least one dose of tacrolimus 3 mg. The median duration of treatment was 359 days. 145 patients (16.2%) withdrew from the study for adverse events possibly or probably related to tacrolimus, 33 patients (3.7%) withdrew from the study for adverse events unrelated to tacrolimus and 112 (12.5%) withdrew for lack of efficacy. No adverse event with an incidence >0.7% appeared for the first time after the first 3 months of treatment with 3 mg tacrolimus. 529 patients (59%) experienced an adverse event that was possibly or probably related to tacrolimus; the most common were diarrhoea (14.6%), nausea (10.3%), tremor (9.0%), headache (8.7%), abdominal pain (7.9%), dyspepsia (7.6%), increased creatinine (6.8%) and hypertension (5.4%). Twenty-four patients (2.7%) experienced serious adverse events possibly or probably related to study drug; the most common were pneumonia (0.6%), hyperglycaemia (0.3%), gastroenteritis (0.2%), pancreatitis (0.2%) and diabetes mellitus (0.2%). The mean creatinine level increased from 67+/-19 micromol/l (0.76+/-0.22 mg/dl) at baseline to 75+/-26 micromol/l (0.85+/-0.30 mg/dl) (P<0.0001) at end of treatment. 351 (40.3%) of the 872 patients for whom creatinine levels were available at both baseline and during treatment had > or =30% increase from baseline in serum creatinine during the study, either related or unrelated to tacrolimus, with 73 patients (8.4%) having creatinine levels exceeding the normal range. At end of treatment, 177 patients (20.3%) had a > or =30% increase from baseline in creatinine. Serum creatinine remained within the normal range throughout the trial in approximately 90% of patients. At the end of treatment, the ACR20, ACR50 and ACR70 response rates were 38.4%, 18.6% and 9.0% respectively. Over 26% of patients had at least a 70% improvement in both swollen and painful/tender joints. CONCLUSION: This study demonstrates that tacrolimus was safe and well-tolerated and provided clinical benefit over a period of at least 12 months.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Imunossupressores/efeitos adversos , Tacrolimo/efeitos adversos , Idoso , Anti-Inflamatórios não Esteroides/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/sangue , Artrite Reumatoide/fisiopatologia , Pressão Sanguínea/fisiologia , Creatinina/sangue , Diabetes Mellitus/induzido quimicamente , Feminino , Humanos , Imunossupressores/uso terapêutico , Assistência de Longa Duração/métodos , Masculino , Pessoa de Meia-Idade , Tacrolimo/uso terapêutico , Resultado do Tratamento , Tremor/induzido quimicamente
2.
Cell Mol Biol (Noisy-le-grand) ; 49(2): 193-207, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12887102

RESUMO

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.


Assuntos
Autoanticorpos/imunologia , Idiótipos de Imunoglobulinas/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Animais , Artrite Reumatoide/imunologia , Humanos , Interleucina-2/metabolismo , Lúpus Eritematoso Sistêmico/imunologia , Camundongos , Linfócitos T
3.
Springer Semin Immunopathol ; 23(1-2): 63-72, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11455862

RESUMO

It is clear that the rate of infection is increased in most of the more serious forms of autoimmune disease and agents such as high-dose steroids and the alkylating agents increase this risk. Other agents such as MTX, CsA, LEF, AZA and the TNF antagonists do not appear to increase the risk of infection given either alone or in combination. Similarly, the risk of malignancy in certain types of autoimmune disease appears increased. However, other than the alkylating agents, none of the agents used appear to increase this risk. The more recently released agents such as CsA, LEF and the TNF antagonists need longer durations of follow-up to substantiate this, however. It is clear that, unless they are absolutely necessary, one should avoid the alkylating agents used either alone or in combination to avoid problems with infection and malignancy. In addition, the use of steroids should be kept as low as possible to avoid infections. It is possible that the use of the more benign agents alone and in combination earlier in the disease course may help to reduce both infection and the incidence of malignancy in the long run.


Assuntos
Corticosteroides/uso terapêutico , Alquilantes/uso terapêutico , Doenças Autoimunes/terapia , Infecções/etiologia , Neoplasias/etiologia , Corticosteroides/efeitos adversos , Alquilantes/efeitos adversos , Antirreumáticos/efeitos adversos , Antirreumáticos/uso terapêutico , Doenças Autoimunes/complicações , Relação Dose-Resposta a Droga , Interações Medicamentosas , Quimioterapia Combinada , Humanos , Infecções/induzido quimicamente , Neoplasias/induzido quimicamente
4.
J Clin Rheumatol ; 7(1): 3-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17039079

RESUMO

This report describes the results of a clinic-based study conducted to verify a community-reported excess prevalence of systemic lupus erythematosus (SLE) and a possible connection between ethnicity and environmental factors in the reporting of SLE in the United States-Mexico border town of Nogales, Arizona. A community group in Nogales reported 37 cases of SLE in its community, suggesting a prevalence rate of 200 per 100,000. This report describes 19 definite and 7 probable cases of SLE using the 1982 American College of Rheumatology criteria. All definite and probable cases were self-identified, Mexican-American females. This yields a prevalence rate of 94 per 100,000, among the highest reported to date. The majority of cases resided within 3 miles of the United States-Mexico border and within 1 mile of the polluted Nogales Wash or ground wells with documented toxins. It remains to be determined whether this confirms that SLE is more common in Mexican-Americans or whether environmental factors, especially pollutants, are predominantly responsible. In addition to the need to be aware about the apparent increased risk of SLE in many Latin-Americans, clinicians should ask about possible environmental factors.

5.
J Rheumatol ; 27(8): 1855-63, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10955324

RESUMO

OBJECTIVE: To determine the safety and potential clinical efficacy of primary and booster injections of a DR4/1 peptide in patients with active rheumatoid arthritis (RA) despite methotrexate therapy. METHODS. Subjects with active RA were enrolled in a randomized, placebo controlled, double blind, dose-escalating clinical trial of synthetic DR4/1 peptide containing the shared epitope. The primary injection of the DR4/1 peptide in alum adjuvant was administered at one of 3 doses, 1.3, 4.0, and 13 mg, followed by up to 3 or 4 booster injections every 6 or 8 weeks at the same dose. The primary outcomes were the occurrence of adverse effects and changes in measures of immune function. Clinical efficacy was assessed using the American College of Rheumatology 20% criteria for clinical improvement. RESULTS: Fifty-three patients were entered into the trial, including 44 who completed the study. In the absence of any observations of a dose response to the DR4/1 peptide injections, the 3 dosage groups were combined for subsequent analysis into 3 groups: patients receiving DR4/1 peptide injections every 6 weeks, patients receiving DR4/1 peptide injections every 8 weeks, and a placebo group. At all doses and each dosing interval the primary and booster injections of synthetic DR4/1 peptide were well tolerated and did not produce any significant changes in lymphocyte counts or evidence of generalized immunosuppression. Analysis of clinical efficacy showed that the 6 week group had trends toward improvement in disease measures. CONCLUSION: Primary and booster injections of the DR4/1 peptide containing the shared epitope were safe and did not broadly suppress immune function.


Assuntos
Artrite Reumatoide/terapia , Antígeno HLA-DR4/uso terapêutico , Oligopeptídeos/uso terapêutico , Adolescente , Adulto , Idoso , Artrite Reumatoide/imunologia , Linfócitos B/imunologia , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Citometria de Fluxo , Antígeno HLA-DR4/efeitos adversos , Antígeno HLA-DR4/imunologia , Humanos , Imunização Secundária , Injeções Intramusculares , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Masculino , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Monócitos/imunologia , Oligopeptídeos/efeitos adversos , Oligopeptídeos/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Segurança , Linfócitos T/imunologia , Resultado do Tratamento
6.
J Protein Chem ; 19(1): 9-21, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10882168

RESUMO

Natural autoantibodies to the T-cell receptor (Tcr) have been identified in all human sera. However, titer, epitope specificity, and isotype vary with physiological conditions, autoimmune diseases, and retroviral infections. The levels of anti-Tcr autoantibodies in rheumatoid arthritis (RA) patients are significantly higher than in normal individuals, and the autoantibodies are typically IgM. To obtain detailed information on these autoantibodies, we generated B-cell heterohybridomas secreting monoclonal IgM autoantibodies (mAAbs) from the synovial tissue and peripheral blood of RA patients. We selected clones secreting mAAbs that bound a major Vbeta epitope defined by a synthetic peptide that contains the CDR1 region of the Vbeta 8.1 gene product. From these we isolated a subset of seven mAAbs that bound a recombinant single-chain Valpha/Vbeta construct containing the peptide epitope and, also to JURKAT cells which express Vbeta 8.1. The mAAbs produced by these clones were distinct from each other in their V-region sequences. However, all the V regions were essentially identical to germline sequences in both the heavy and light chains. Heavy-chain CDR3 segments ranged in length from 17 to 26 residues, did not correspond to any known autoantibodies, and showed extensive N-region diversity in the V(D)J junctions. Five monoclonal autoantibodies use VH 3 genes, while the remaining two utilized VH 4 sequences. Light-chain variable regions used were Vkappa3 (two), Vlambda3 (four), and one Vlambda2. These autoantibodies derived their unique features from their CDR3 segments that could not be aligned with any known sequences.


Assuntos
Anticorpos Monoclonais/imunologia , Artrite Reumatoide/imunologia , Imunoglobulina M/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Sequência de Aminoácidos , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/química , Anticorpos Monoclonais/genética , Especificidade de Anticorpos , Autoanticorpos/biossíntese , Autoanticorpos/química , Autoanticorpos/genética , Autoanticorpos/imunologia , Sítios de Ligação de Anticorpos/genética , Ensaio de Imunoadsorção Enzimática , Humanos , Hibridomas/metabolismo , Imunoglobulina M/biossíntese , Imunoglobulina M/química , Imunoglobulina M/genética , Células Jurkat , Leucócitos/metabolismo , Leucócitos Mononucleares/metabolismo , Dados de Sequência Molecular , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Alinhamento de Sequência , Análise de Sequência de Proteína , Membrana Sinovial/imunologia
7.
Appl Biochem Biotechnol ; 83(1-3): 31-49; discussion 49-52, 145-53, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10826947

RESUMO

To characterize the binding specificity and light- and heavy-chain variable region usage in monoclonal human autoantibodies (mAAbs) to T-cell receptors, we constructed heterohybridomas from peripheral blood B cells of three rheumatoid arthritis (RA) patients. From a panel of more than 200 heterohybridomas secreting IgM autoantibodies binding to T-cell receptor Vbeta chain first complementarity determining segments (CDR1), we characterized two IgM/lambda molecules from a single patient in detail. These bound to both CDR1 peptide epitopes and intact TCR of recombinant single-chain T-cell receptor constructs, and to T-cell surface TCR. Spectratype analysis using epitopes mimicking a set of 24 Vbeta genes indicated that one molecule bound only a few members of the set, whereas the second showed considerable epitope promiscuity by binding to more than half of the tested CDR1 peptides. Both mAAbs used variants of a Vlambda3 gene that were very similar to one another and to the germline gene. The epitope-promiscuous autoantibody used a V(H)4 gene identical to a germline prototype, while the other incorporated a V(H)3 sequence differing in only a single residue from its germline prototype. The CDR3s of both were large and distinct from each other as well as from the corresponding segments of rheumatoid factors and "cold agglutinins" using the same or related V(H) germline genes. These mAAbs offer models for deciphering the basis of epitope promiscuity, and serve as candidates for direct use in immunomodulation because they are of intrinsic human origin and do not require molecular engineering to adapt them for use in therapy.


Assuntos
Anticorpos Monoclonais/genética , Autoanticorpos/genética , Receptores de Antígenos de Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Linfócitos B/imunologia , Epitopos/genética , Genes de Imunoglobulinas , Humanos , Hibridomas/imunologia , Imunoglobulina M/genética , Região Variável de Imunoglobulina/genética , Camundongos , Dados de Sequência Molecular , Peptídeos/genética , Peptídeos/imunologia , Receptores de Antígenos de Linfócitos T/genética , Fator Reumatoide/genética , Fator Reumatoide/imunologia , Homologia de Sequência de Aminoácidos
8.
Rheumatology (Oxford) ; 39(2): 156-64, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10725065

RESUMO

OBJECTIVE: To compare the safety, tolerability and efficacy of the new oral microemulsion formulation of cyclosporin A (CyA; Sandimmun Neoral) and the original CyA formulation (Sandimmun), in patients with severe active rheumatoid arthritis (RA), over a 12-month period. METHODS: In this double-blind, multicentre study, patients were randomized to treatment with Neoral or Sandimmun, starting with 2.5 mg/kg/day, with dose adjustments after 4 weeks. Primary efficacy criteria included patients' assessment of disease activity. Pharmacokinetic and safety assessments were performed at regular intervals. RESULTS: Compared with Sandimmun, Neoral showed a consistent trend towards greater clinical efficacy from week 12 onwards, including a significant difference in patients' assessment of disease activity at the study end-points. A significantly lower increase in dose from baseline was observed with Neoral at week 24. Pharmacokinetic assessments at week 24 showed increased absorption and decreased variability with Neoral. No differences in safety were found between treatment groups. CONCLUSION: These observations indicate that Neoral is as safe and at least as effective as Sandimmun and have important implications for patient management given the increasing role for CyA in the treatment of severe, active RA.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Ciclosporina/uso terapêutico , Antirreumáticos/administração & dosagem , Antirreumáticos/efeitos adversos , Artrite Reumatoide/sangue , Pressão Sanguínea/efeitos dos fármacos , Química Farmacêutica , Creatinina/sangue , Ciclosporina/administração & dosagem , Ciclosporina/efeitos adversos , Método Duplo-Cego , Emulsões , Humanos , Articulações/efeitos dos fármacos , Articulações/patologia , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Segurança , Índice de Gravidade de Doença , Resultado do Tratamento
9.
Rheum Dis Clin North Am ; 26(1): 145-59, x-xi, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10680202

RESUMO

Stress and pain mechanisms are complex and share many central nervous system pathways. Both are critical issues for patients with rheumatoid arthritis and other connective tissue diseases. The link between stress and neuroendoimmune function suggests that alternative therapies focusing on improved psychologic and metabolic function could significantly change patients' pain outcomes. Programs using alternative therapies such as tai chi and meditation in combination with traditional medications appear to be beneficial for patients with arthritis. These individuals appear to live better lives and may have better long-term outcomes.


Assuntos
Terapia Comportamental , Terapia por Exercício , Manejo da Dor , Doenças Reumáticas/terapia , Estresse Fisiológico/terapia , Terapias Complementares , Humanos , Dor/etiologia , Dor/imunologia , Educação de Pacientes como Assunto , Doenças Reumáticas/complicações , Doenças Reumáticas/imunologia , Estresse Fisiológico/etiologia , Estresse Fisiológico/imunologia
10.
Semin Arthritis Rheum ; 29(1): 27-35, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10468412

RESUMO

OBJECTIVES: To provide: 1) a brief review of current thought on the role of T cells in the pathogenesis of rheumatoid arthritis (RA); and 2) To provide an overview of RA therapies directed against T cells. METHODS: The following papers in relevant American and European medical journals were reviewed. Those related to: the role of T cells in the pathogenesis of RA; to biological therapy directed against cell surface markers specific to T cell populations implicated in RA; and to treatment of RA with cyclosporin A and leflunomide, pharmacological agents known to interfere with the T cell response to antigens. RESULTS: Although a variety of cell types are now recognized as contributors to the progressive joint destruction that is a hallmark of RA, T cell activation is still thought to be a central event in the initiation and progression of this disease. As a result, various therapeutic options directed against T cells have been developed. These include biological agents directed against specific populations of activated T cells and pharmacological agents that have specific T cell-modulatory actions. CONCLUSIONS: Use of T cell-directed biological therapies for RA has been disappointing, as a result of both lack of efficacy and serious toxicity. Treatment of RA with pharmacological agents that interfere with antigen-driven T cell proliferation has been more successful.


Assuntos
Artrite Reumatoide/imunologia , Artrite Reumatoide/terapia , Linfócitos T/imunologia , Anti-Inflamatórios não Esteroides/uso terapêutico , Antígenos CD/imunologia , Células Clonais/imunologia , Predisposição Genética para Doença , Humanos , Imunossupressores/uso terapêutico , Imunoterapia , Isoxazóis/uso terapêutico , Leflunomida , Ativação Linfocitária/imunologia , Linfócitos T/efeitos dos fármacos
11.
Drugs Today (Barc) ; 35(4-5): 295-307, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-12973434

RESUMO

Rheumatoid arthritis (RA) is a chronic inflammatory process of unknown etiology affecting 1% of the population worldwide. It results in excess morbidity in a majority of cases and early mortality in patients with aggressive disease. Early immunohistologic studies of the rheumatoid synovium demonstrate that T-cells, especially cluster of differentiation (CD)4(+) cells, are a major component of the infiltrating inflammatory cells. It has also been demonstrated that RA patients share a common major histocompatibility complex (MHC) class II molecule, HLA-DR4. Immune activation by T-cells requires the formation of the antigen recognition complex composed of the T-cell receptor, the MHC II molecule, and antigen. Many treatment modalities for RA have targeted the T-cell and/or the antigen recognition complex. These have varied from relatively crude methods such as leukopheresis to very specific monoclonal antibodies directed toward specific T-cell antigens such as the CD4 molecule itself. Not only have these therapies been effective, but also they have provided some interesting data on the pathogenesis of RA. Unfortunately, some have been associated with harmful side effects. To date, the safest and most effective modality has been immunomodulatory drugs such as cyclosporin and FK506, either alone or in combination with other agents. It appears that the earlier these treatments are started in the course of RA, the more effective they are, not only in controlling disease but also in achieving a potential remission.

13.
Curr Opin Rheumatol ; 10(4): 319-25, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9725093

RESUMO

Whereas it is clear that HLA-B27 is increased in many North American natives, the prevalence varies a great deal. There is still a paucity of data on a large number of tribes. There is, however, a suggestion that HLA-B27 positive prevalence follows cultural/linguistic groupings. Reactive arthritis, sacroiliitis, and ankylosing spondylitis also appear to be increased in these people, but their relationship to HLA-B27 and possibly additional genetic predisposing factors is far from clear. Given these data and the known association of infectious agents, more extensive studies are warranted, especially in those tribes with a large enough population to achieve statistical significance.


Assuntos
Artrite/etnologia , Antígeno HLA-B27 , Indígenas Norte-Americanos , Artrite/imunologia , Humanos
15.
J Rheumatol ; 25(7): 1257-62, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9676753

RESUMO

OBJECTIVE: The goal of this single infusion, dose escalation study was to evaluate the safety of the PRIMATIZED anti-CD4 monoclonal antibody (Mab), IDEC-CE9.1, in patients with rheumatoid arthritis (RA). METHODS: Twenty-five patients received single infusions of IDEC-CE9.1 in dose escalation form (0.03 to 4 mg/kg). Cohorts consisted of 3 patients each with seropositive RA. Following treatment, patients were monitored for 2 weeks before initiation of treatment of the next cohort. Peripheral blood samples were taken during and after treatment to measure immune function. Flow cytometry of peripheral blood mononuclear cells and in vitro proliferative responses to antigens and recall antigens were assessed pre and post-treatment. Cell surface markers CD3, CD4 (OKT4 and Leu 3a), CD8, CD20, CD25, CD45Ro, CD45Ra and DR were analyzed, and proliferation to mitogens and recall antigens was measured. RESULTS: No infusion related adverse events were noted and other drug related adverse events were mild. Reduction in peripheral CD4 T cell number was brief (3 to 7 days) and not associated with infection. CD4 cell surface antigen downmodulation was observed postinfusion. Suppression of CD25 expression was associated with a positive clinical response. In vitro proliferative responses to mitogens and antigen were inhibited for up to one month with no association to positive clinical response. CONCLUSION: IDEC-CE9.1 appears to have a benign safety profile and may modulate immune function rather than deplete CD4+ T cells.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Antígenos CD4/imunologia , Adulto , Idoso , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/sangue , Antígenos CD/análise , Artrite Reumatoide/imunologia , Contagem de Linfócito CD4/efeitos dos fármacos , Relação Dose-Resposta Imunológica , Feminino , Humanos , Macaca/imunologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
16.
J Clin Invest ; 101(7): 1362-71, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9525978

RESUMO

Proinflammatory cytokines, including tumor necrosis factor (TNF) and interleukin 1 (IL-1), mediate the joint destruction that characterizes rheumatoid arthritis (RA). Previous studies have shown that parathyroid hormone-related protein (PTHrP) is a member of the cascade of proinflammatory cytokines induced in parenchymal organs during lethal endotoxemia. To test the hypothesis that NH2-terminal PTHrP, a potent bone resorbing agent, could also be a member of the synovial cascade of tissue-destructive cytokines whose expression is induced in RA, PTHrP expression was examined in synovium and synoviocytes obtained from patients with RA and osteoarthritis (OA). PTHrP production, as determined by measurement of immunoreactive PTHrP(1-86) in tissue explant supernatants, was increased 10-fold in RA versus OA synovial tissue. Synovial lining cells and fibroblast-like cells within the pannus expressed both PTHrP and the PTH/PTHrP receptor, findings that were confirmed by in vitro studies of cultured synoviocytes. TNF-alpha and IL-1beta stimulated PTHrP expression in synoviocytes, while dexamethasone and interferon-gamma, agents with some therapeutic efficacy in the treatment of RA, inhibited PTHrP release. Treatment of synoviocytes with PTHrP(1-34) stimulated IL-6 secretion. These results suggest that proinflammatory cytokine-stimulated production of NH2-terminal PTHrP by synovial tissue directly invading cartilage and bone in RA may mediate joint destruction through direct effects on cartilage or bone, or, indirectly, via the induction of mediators of bone resorption in the tumor-like synovium.


Assuntos
Artrite Reumatoide/metabolismo , Hormônio Paratireóideo/metabolismo , Proteínas/metabolismo , Membrana Sinovial/metabolismo , Células Cultivadas , Dexametasona/farmacologia , Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Humanos , Imuno-Histoquímica , Interferon gama/farmacologia , Interleucina-1/farmacologia , Interleucina-6/farmacologia , Osteoartrite/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo , Proteínas/genética , RNA Mensageiro/genética , Receptor Tipo 1 de Hormônio Paratireóideo , Receptores de Hormônios Paratireóideos/metabolismo , Membrana Sinovial/citologia
17.
J Rheumatol ; 24(6): 1031-6, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9195505

RESUMO

OBJECTIVE: A 24 week study of subcutaneous (sq) dosing with titration of CAMPATH-1H (C1H) dose against the circulating CD4+ T cell count in patients with rheumatoid arthritis (RA) was undertaken to examine the safety, biologic activity, and clinical efficacy of this approach. METHODS: All patients met American Rheumatism Association (ARA) criteria for active RA. Patients received either 0.5 or 1.0 mg of C1H subcutaneously twice per week; dosing could be doubled after the first 8 weeks of treatment and subsequently following 4 week dose intervals for lack of clinical efficacy, but was discontinued any time the CD4+ T cell count fell below 400/mm3. Patients were evaluated weekly for 2 weeks and then biweekly for clinical and laboratory variables of safety, biological activity, and disease activity. RESULTS: Ten patients were treated, 6 in the 0.5 mg cohort and 4 in the 1.0 mg cohort. Four of ten patients had a 20% modified Paulus response (2 in each cohort) while taking drug; there were minimal side effects, primarily limited to local reaction at the injection site. All patients had a > 50% drop in circulating CD4+ T cells within the first 2 weeks of therapy, with no further significant reduction; only 1/6 patients in the 0.5 mg cohort had dose limiting CD4+ T cell depression vs 2/4 in the 1.0 mg cohort. All patients developed antibodies to C1H. Appearance of anti-C1H was temporarily associated with a halt in further reduction of CD4+ T cell count despite continued C1H administration. CONCLUSION: Subcutaneous administration of C1H in low doses (0.5 mg biweekly) was well tolerated and did not result in dose limiting CD4+ T cell depletion in 5 of 6 patients. Clinical efficacy was observed in some patients but could not be maintained, possibly due to the production of anti-C1H antibodies.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Antineoplásicos/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Alemtuzumab , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Anticorpos Antineoplásicos/imunologia , Anticorpos Antineoplásicos/farmacologia , Antirreumáticos/imunologia , Antirreumáticos/farmacologia , Artrite Reumatoide/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
19.
Br J Rheumatol ; 35 Suppl 2: 19-23, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8810686

RESUMO

The role of combination therapy in rheumatoid arthritis (RA) is increasing with the development of new treatment modalities. Past combinations of slow-acting anti-rheumatic drugs resulted in either excessive side-effects or lack of efficacy over single-agent therapy. However, refined methodology and a better understanding of the mechanism of action of newer agents have led to improved combinations, which appear more promising. In particular, in a 6 month, randomized, double-blind trial, the combination of cyclosporin (CyA) with methotrexate was found to be more efficacious than methotrexate alone, providing enhanced clinical benefit, without evidence of increased adverse events. The mean final dose of 2.97 mg/kg per day CyA in combination was lower than that required for CyA monotherapy. Further, a new formulation of CyA, with improved bioavailability, should provide enhanced efficacy and an acceptable safety profile, not only as monotherapy but also in combination with agents such as methotrexate. These developments offer new hope to patients with progressive RA, which is unresponsive to conventional therapy.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Ciclosporina/uso terapêutico , Quimioterapia Combinada , Previsões , Humanos , Metotrexato/uso terapêutico , Reumatologia/tendências
20.
J Rheumatol Suppl ; 44: 75-7, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8833059

RESUMO

The role of combination therapy in rheumatoid arthritis is increasing with the recent development of various new treatment modalities. While past combinations of slow acting antirheumatic drugs have resulted in either excessive side effects or lack of efficacy over single agent therapy, recent combinations appear more promising. Recently, the combination of cyclosporine and methotrexate (MTX) was shown to be more efficacious than MTX alone. Improved methodology and a better understanding of the mechanisms of action of these newer agents is responsible for these exciting results.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Ciclosporina/uso terapêutico , Quimioterapia Combinada , Previsões , Humanos
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