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1.
Autoimmun Rev ; 21(10): 103164, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35926768

RESUMO

Abdominal aortic aneurism (AAA) is a complex immunological disease with a strong genetic component, and one of the ten leading causes of death of individuals 55-74 years old worldwide. Strong evidence has been accumulated suggesting that AAA is an autoimmune specific antigen-driven disease. Mononuclear cells infiltrating AAA lesions comprised of T and B lymphocytes and other cells expressing early-, intermediate- and late-activation antigens, and the presence of antigen-presenting cells have been documented, demonstrating an ongoing immune response. The three components of the trimolecular complex, T-cell receptor (TCR)/peptide (antigen)/HLA have been identified in AAA, and specifically: (i) clonal expansions of T-cell clones in AAA lesions; (ii) the association of AAA with particular HLA Class I and Class II; and (iii) self or nonself putative AAA-associated antigens. IgG autoantibodies recognizing proteins present in normal aortic tissue have been reported in patients with AAA. Molecular mimicry, defined as the sharing of antigenic epitopes between microorganisms (bacteria, viruses) and self antigens, maybe is responsible for T-cell responses and antibody production in AAA. Also, the frequency and the suppressor activity of CD4+ CD25+ FOXP3+ Tregs and the expression of FOXP3 transcripts and protein have been reported to be significantly impaired in AAA patients vs normal donors.


Assuntos
Aneurisma da Aorta Abdominal , Idoso , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/patologia , Autoanticorpos , Autoantígenos , Epitopos , Fatores de Transcrição Forkhead , Humanos , Imunoglobulina G , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T
2.
PLoS One ; 14(7): e0218990, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31310631

RESUMO

Abdominal aortic aneurysm (AAA) is a life-threatening immunological disease responsible for 1 to 2% of all deaths in 65 year old or older individuals. Although mononuclear cell infiltrates have been demonstrated in AAA lesions and autoimmunity may be responsible for the initiation and account for the propagation of the disease, the information available about the pathogenesis of AAA is limited. To examine whether AAA lesions from patients with AAA contain clonally expanded α-chain TCR transcripts, we amplified by the non-palindromic adaptor-PCR (NPA-PCR)/Vα-specific PCR and/or the Vα-specific PCR these α-chain TCR transcripts. The amplified transcripts were cloned and sequenced. Substantial proportions of identical α-chain TCR transcripts were identified in AAA lesions of 4 of 5 patients, demonstrating that clonally expanded T cells are present in these AAA lesions. These results were statistically significant by the bimodal distribution. Three of 5 of these patients were typed by DNA-based HLA-typing and all three expressed DRB1 alleles containing the DRßGln70 amino acid residue that has been demonstrated to be associated with AAA. All three patients exhibited clonally expanded T cells in AAA lesions. Four of the 5 patients with AAA who exhibited clonal expansions of α-chain TCR transcripts, also exhibited clonal expansions of ß-chain TCR transcripts in AAA lesions, as we have demonstrated previously (J Immunol 192:4897, 2014). αß TCR-expressing T cells infiltrating AAA lesions contain T-cell clones which have undergone proliferation and clonal expansion in vivo in response to as yet unidentified specific antigens that may be self or nonself. These results provide additional evidence supporting the hypothesis that AAA is a specific antigen-driven T-cell autoimmune disease.


Assuntos
Antígenos/genética , Aneurisma da Aorta Abdominal/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Transcrição Gênica , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos/genética , Antígenos/imunologia , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/patologia , Células Cultivadas , Células Clonais/imunologia , Humanos , Masculino , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Análise de Sequência de RNA , Linfócitos T/imunologia , Linfócitos T/patologia
3.
Autoimmun Rev ; 13(11): 1114-20, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25182207

RESUMO

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by the presence of rheumatoid factor (RF) and anti-citrullinated protein/peptide autoantibodies (ACPAs). Citrulline derives from arginine by peptidyl arginine deiminases, and ACPAs are directed against different citrullinated antigens, including fibrinogen, fibronectin, α-enolase, collagen type II, histones. ACPAs are present in two thirds of RA patients have higher specificity than RF for RA, and are associated with joint radiographic damage and extra-articular manifestations and they are detected years before the onset clinical arthritis. Recent studies suggest that citrullinated antigens are most likely arthritogenic autoantigens in RA. ACPA production is associated with the HLA-DRB1 shared epitope (HLA-DRB1 SE) and accounts for the well-known RA-HLA-DRB1 SE association, as T cells recognize citrullinated peptides. Smoking and periodontitis, known environmental risk factors for RA promote protein citrullination and ACPA production. Cirullinated proteins are capable of inducing arthritis in transgenic mice carrying HLA-DRB1 SE genes, and ACPAs induce macrophage TNF-α production, osteoclastogenesis and complement activation. They also induce the formation of neutrophil extracellular traps (NETs). NETs, increased in RA, are a source of citrullinated autoantigens in RA and induce fibroblast interleukin-8 production. This knowledge is likely to have therapeutic implications, as there is a need of matching therapy with patient profile. Abatacept, a T cell activation modulator, is the best therapy for ACPA(+) RA patients, although clinical data are sparse at present. Rituximab, a monoclonal antibody that depletes B cells, is also the best therapy for ACPA(+) RA patients, and clinical data support this view.


Assuntos
Artrite Reumatoide/imunologia , Autoantígenos/imunologia , Citrulina/imunologia , Animais , Artrite Reumatoide/tratamento farmacológico , Linfócitos B/imunologia , Humanos , Peptídeos/imunologia
5.
J Immunol ; 192(10): 4897-912, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24752442

RESUMO

Abdominal aortic aneurysm (AAA) is a common disease with often life-threatening consequences. This vascular disorder is responsible for 1-2% of all deaths in men aged 65 years or older. Autoimmunity may be responsible for the pathogenesis of AAA. Although it is well documented that infiltrating T cells are essentially always present in AAA lesions, little is known about their role in the initiation and/or progression of the disease. To determine whether T cells infiltrating AAA lesions contain clonally expanded populations of T cells, we amplified ß-chain TCR transcripts by the nonpalindromic adaptor-PCR/Vß-specific PCR and/or Vß-specific PCR, followed by cloning and sequencing. We report in this article that aortic abdominal aneurysmal lesions from 8 of 10 patients with AAA contained oligoclonal populations of T cells. Multiple identical copies of ß-chain TCR transcripts were identified in these patients. These clonal expansions are statistically significant. These results demonstrate that αß TCR(+) T lymphocytes infiltrating aneurysmal lesions of patients with AAA have undergone proliferation and clonal expansion in vivo at the site of the aneurysmal lesion, in response to unidentified self- or nonself Ags. This evidence supports the hypothesis that AAA is a specific Ag-driven T cell disease.


Assuntos
Aneurisma da Aorta Abdominal/imunologia , Proliferação de Células , Seleção Clonal Mediada por Antígeno , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Linfócitos T/imunologia , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linfócitos T/patologia
6.
Cell Immunol ; 266(2): 143-53, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21055733

RESUMO

IL-10 transcripts were expressed in 14/15 primary breast adenocarcinomas and in 5/8 established breast tumor lines. Immunohistochemistry and immunoprecipitation from lysates and supernatants revealed that established breast tumor lines produced IL-10 protein. Immunohistochemistry revealed that IL-10 is localized to tumor cells of primary breast adenocarcinomas and to occasional infiltrating MNC. Established breast tumor cell lines expressed IL-12p40 transcripts (6/8) and protein (4/7) and IL-12p35 transcripts (6/7). Using two sandwich ELISAs, specific, respectively, for IL-12p40 and IL-12p70 proteins, we demonstrated that established breast tumor cell lines produce IL-12p40 monomer/homodimer, but not IL-12p70. Positive staining for IL-12p70 in primary breast adenocarcinomas was found only in MNC infiltrating the tumor while tumor cells were negative. IL-12p40 homodimer/monomer inhibit as antagonists IL-12 or IL-23, although they may also act as agonists and positive regulators. Also, primary breast adenocarcinomas (15/15) and established breast tumor cell lines (6/8) expressed TGF-ß1 transcripts. IL-10, IL-12p40 and TGF-ß1 may inhibit substantially the anti-tumor immune response.


Assuntos
Adenocarcinoma/imunologia , Neoplasias da Mama/imunologia , Interleucina-10/biossíntese , Subunidade p40 da Interleucina-12/biossíntese , Adenocarcinoma/metabolismo , Adulto , Idoso , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Interleucina-10/análise , Subunidade p35 da Interleucina-12/análise , Subunidade p35 da Interleucina-12/biossíntese , Subunidade p40 da Interleucina-12/análise , Interleucina-23/agonistas , Interleucina-23/antagonistas & inibidores , Interleucina-23/biossíntese , Pessoa de Meia-Idade , Fator de Crescimento Transformador beta1/análise , Fator de Crescimento Transformador beta1/imunologia
7.
Anticancer Res ; 29(11): 4673-82, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20032419

RESUMO

The expression of the CD3zeta subunit was investigated in fresh (uncultured) tumor-infiltrating lymphocytes (TILs) isolated from either solid tumor (ST) specimens or ascites (ASC) from patients with epithelial ovarian carcinoma (EOC). Western blot analysis of CD3zeta immunoprecipitates using anti-CD3zeta rabbit serum revealed that in 6 out of 6 patients with EOC, the CD3zeta protein was absent from ST-TILs. Immunoprecipitation with anti-phosphotyrosine monoclonal antibody (anti-PY20) from ST-TILs from one patient revealed bands co-migrating with the phosphorylated CD3zeta. CD3zeta protein was found to be expressed in only 1 out of 7 ST-TILs from patients with EOC. ASC-TILs were available in 5 of these patients and immunoprecipitation/Western blotting experiments using anti-CD3zeta rabbit serum revealed that CD3zeta protein was expressed in all 5. In addition, CD3zeta protein was expressed in 3 additional ASC-TIL specimens for which ST-TILs were not available. Therefore, the CD3zeta protein was expressed in ASC-TIL isolated from 8 out of 8 patients with EOC. CD3zeta protein was also expressed on peripheral blood mononuclear cells (PBMCs) from patients with EOC and from normal donors. RT-PCR studies of fresh ST-TIL specimens, using CD3zeta-specific primers, revealed that CD3zeta transcripts were absent from 13 out of 21 patients with EOC, down-regulated in 4 patients and present at levels comparable to those found in PBMCs in 4 other patients. In contrast, CD3delta transcripts were present at comparable levels in all specimens. Treatment with recombinant interleukin-2 (rIL-2) (600 IU/ml) restored the expression of CD3zeta protein and transcripts in cultured ST-TILs, whereas fresh ST-TILs did not express CD3zeta, in contrast to fresh ASC-TILs. These results demonstrate differential expression of CD3zeta in ST-TILs versus ASC-TILs in patients with EOC. CD3zeta transcripts and protein were found to be absent from most ST-TILs from patients with EOC, whereas they were expressed in ASC-TILs and PBMCs from such patients.


Assuntos
Complexo CD3/biossíntese , Linfócitos do Interstício Tumoral/imunologia , Neoplasias Ovarianas/imunologia , Idoso , Idoso de 80 Anos ou mais , Ascite/metabolismo , Ascite/patologia , Regulação para Baixo , Feminino , Humanos , Imunoprecipitação , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , Pessoa de Meia-Idade , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/patologia , Fosforilação , Tirosina/metabolismo
9.
Immunol Res ; 38(1-3): 359-72, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17917046

RESUMO

We are investigating the hypothesis that most human autoimmune diseases are specific antigen-driven T-cell diseases. T-cell clones responding to specific antigenic epitopes are responsible for the initiation and/or the propagation of these diseases. Similarly, specific antigen-driven T-cell responses are responsible for the rejection of organ allografts and the immune response to tumors. Activated T cells provide the "engine" for the chronic inflammation that is associated with autoimmune diseases, organ graft rejection and tumor immunity. The best way to identify whether specific antigen-driven T cell responses are involved in the initiation and/or propagation of these disorders is to investigate whether T cells that infiltrate relevant tissues from these diseases contain monoclonal or oligoclonal, that is to say clonally expanded, populations of T cells. Identification of the T-cell antigen receptor (TCR) transcripts employed by the clonally expanded T cells in these patients permits the identification of the specific antigens that elicit these T-cell responses. These antigens may be responsible for the pathogenesis of these diseases. We will summarize here certain of our findings in this area of research.


Assuntos
Antígenos/análise , Doenças Autoimunes/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Líquido Cefalorraquidiano/imunologia , Humanos , Mimetismo Molecular , Receptores de Antígenos de Linfócitos T/genética , Transcrição Gênica
11.
Ann N Y Acad Sci ; 1085: 224-35, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17182939

RESUMO

To determine whether monoclonal/oligoclonal T cells are present in abdominal aortic aneurysm (AAA) lesions, we amplified beta-chain T cell receptor (TCR) transcripts from these lesions by the nonpalindromic adaptor (NPA)-polymerase chain reaction (PCR)/V-beta-specific PCR followed by cloning and sequencing. Sequence analysis revealed the presence of substantial proportions of identical beta-chain TCR transcripts in AAA lesions in 9 of 10 patients examined, strongly suggesting the presence of oligoclonal populations of alphabeta TCR+ T cells. We have also shown the presence of oligoclonal populations of gammadelta TCR+ T cells in AAA lesions. Sequence analysis after appropriate PCR amplification and cloning revealed the presence of substantial proportions of identical VgammaI and VgammaII TCR transcripts in 15 of 15 patients examined, and of Vdelta1 and Vdelta2 TCR transcripts in 12 of 12 patients. These clonal expansions were very strong. All these clonal expansions were statistically significant by the binomial distribution. In other studies, we determined that mononuclear cells infiltrating AAA lesions express early- (CD69), intermediate- (CD25, CD38), and late- (CD45RO, HLA class II) activation antigens. These findings suggest that active ongoing inflammation is present in the aortic wall of patients with AAA. These results demonstrate that oligoclonal alphabeta TCR+ and gammadelta TCR+T cells are present in AAA lesions. These oligoclonal T cells have been clonally expanded in vivo in response to yet unidentified antigens. Although the antigenic specificity of these T cells remains to be determined, these T cells may play a significant role in the initiation and/or the propagation of the AAA. It appears that AAA is a specific antigen-driven T cell disease.


Assuntos
Antígenos/imunologia , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/imunologia , Doenças Linfáticas/complicações , Doenças Linfáticas/imunologia , Aneurisma da Aorta Abdominal/genética , Humanos , Doenças Linfáticas/genética , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Transcrição Gênica/genética
12.
Nat Clin Pract Rheumatol ; 2(12): 679-85, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17133253

RESUMO

Systemic sclerosis is characterized by extensive fibrosis, microvascular stenosis and autoantibody production. All three characteristics can be accounted for by activation of cells of the immune system. Activation of T cells is antigen-driven and occurs early in the course of the disease, before microscopic evidence of fibrosis. Activated T cells are predominantly of the type 2 T-helper lineage, and produce interleukin-4 and interleukin-13, which induce fibrosis. B cells are also activated early in the course of the disease and, through the production of autoantibodies, cause fibroblasts to adopt a profibrotic phenotype. Macrophages in perivascular infiltrates are activated and produce CC-chemokine ligand 2, transforming growth factor beta and platelet derived growth factor, all of which promote fibrosis and fibroproliferation. These new insights have direct impact on the treatment of patients with systemic sclerosis; therapies that target T cells, B cells and their harmful mediators are a logical approach, and preliminary data are promising.


Assuntos
Linfócitos B/imunologia , Sistema Imunitário/imunologia , Escleroderma Sistêmico/imunologia , Linfócitos T/imunologia , Animais , Linfócitos B/patologia , Modelos Animais de Doenças , Fibrose/imunologia , Fibrose/patologia , Humanos , Sistema Imunitário/patologia , Sistema Imunitário/fisiopatologia , Ativação Linfocitária , Escleroderma Sistêmico/patologia , Escleroderma Sistêmico/fisiopatologia , Escleroderma Sistêmico/terapia , Linfócitos T/patologia
13.
Cell Immunol ; 234(2): 81-101, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16038891

RESUMO

To determine whether clonally expanded T cells are present in tumor specimens from patients with epithelial ovarian carcinoma (EOC) we amplified by the non-palindromic adaptor PCR (NPA-PCR) or by Vbeta-specific PCR beta-chain T-cell receptor (TCR) transcripts from these tumor specimens. The amplified transcripts were cloned and sequenced. Sequence analysis revealed the presence of substantial proportions of multiple identical copies of beta-chain TCR transcripts, suggesting the presence of clonal expansions of T cells in these patients, which were statistically significant by the binomial distribution in seven of nine patients. Independent amplification in separate experiments of beta-chain TCR transcripts from one patient by either NPA-PCR or by Vbeta-specific PCR, followed by cloning and sequencing, revealed identical clonal expansions irrespectively of the amplification method used. Multiple identical copies of beta-chain TCR transcripts can be derived only by specific antigen-driven proliferation and clonal expansion of the T-cell clones which recognize these antigens. Because of the very large size of the TCR repertoire, the probability of finding by chance multiple identical copies of these transcripts within an independent sample of T cells is negligible. These results demonstrate that T cells infiltrating solid tumor specimens or malignant ascites of patients with EOC contain monoclonal/oligoclonal populations of T cells.


Assuntos
Endométrio/imunologia , Neoplasias Ovarianas/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Linfócitos T/imunologia , Adulto , Idoso , Sequência de Aminoácidos , Sequência de Bases , Endométrio/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Alinhamento de Sequência
14.
Hum Immunol ; 66(5): 554-62, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15935893

RESUMO

Substantial evidence has been accumulated suggesting that T cells in patients with epithelial ovarian carcinoma (EOC) exhibit an antigen-driven immune response directed against the tumor cells. In the context of human leukocyte antigen (HLA), this suggests its possible involvement in the disease. Therefore, we examined the distribution of the HLA-DRB1*, -DQA1*, and -DQB1* alleles in 47 patients with EOC and 67 healthy Caucasian women. The frequency of D(70) and E(71) polymorphic residues of the DRB1 alleles was significantly reduced in EOC patients versus controls (pD(70)E(71) = 0.009), suggesting a protective role against the disease. The DQalpha residues R(52) and Y(11)R(55) were increased in the patients (p = 0.008 and 0.012, respectively). Because residues 11 and 55 participate in the formation of pocket 1, they may be functionally important amino acid positions that influence disease susceptibility. The frequency of the DQalpha susceptibility epitope (R(52)Y(11)R(55)) among the DRbetaD(70)E(71)-positive EOC patients was increased when compared with DRbetaD(70)E(71)-positive controls (EOC, 100%; control, 52%; p = 0.028). Among individuals without the DQalpha susceptibility epitope, the distribution of DRbetaD(70)E(71)-positive cases was significantly different between EOC patients and controls (EOC, 0%; control, 60%; p = 0.039). Therefore, it appears that the presence of DQalpha susceptibility elements overrides the protective effect of the DRbetaD(70)E(71) epitope and suggests an interactive relationship between DRbeta and DQalpha epitopes that may be of importance for disease susceptibility. Because positions DRbeta 70,71 and DQalpha 52 have been implicated in immunologic diseases, it is likely that besides being critical for T-cell recognition, they may also play a role in T-cell development and acquisition of the T-cell repertoire.


Assuntos
Predisposição Genética para Doença/genética , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Sequência de Aminoácidos/genética , Suscetibilidade a Doenças/imunologia , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Feminino , Frequência do Gene/genética , Frequência do Gene/imunologia , Antígenos HLA-DQ/imunologia , Cadeias alfa de HLA-DQ , Antígenos HLA-DR/imunologia , Teste de Histocompatibilidade , Humanos , Dados de Sequência Molecular , Neoplasias Epiteliais e Glandulares/imunologia , Neoplasias Ovarianas/imunologia , Polimorfismo Genético/genética , Polimorfismo Genético/imunologia
16.
Clin Microbiol Rev ; 17(1): 174-207, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14726460

RESUMO

Both genetic background and environmental factors, very probably viruses, appear to play a role in the etiology of multiple sclerosis (MS). Lessons from viral experimental models suggest that many different viruses may trigger inflammatory demyelinating diseases resembling MS. Theiler's virus, a picornavirus, induces in susceptible strains of mice early acute disease resembling encephalomyelitis followed by late chronic demyelinating disease, which is one of the best, if not the best, animal model for MS. During early acute disease the virus replicates in gray matter of the central nervous system but is eliminated to very low titers 2 weeks postinfection. Late chronic demyelinating disease becomes clinically apparent approximately 2 weeks later and is characterized by extensive demyelinating lesions and mononuclear cell infiltrates, progressive spinal cord atrophy, and axonal loss. Myelin damage is immunologically mediated, but it is not clear whether it is due to molecular mimicry or epitope spreading. Cytokines, nitric oxide/reactive nitrogen species, and costimulatory molecules are involved in the pathogenesis of both diseases. Close similarities between Theiler's virus-induced demyelinating disease in mice and MS in humans, include the following: major histocompatibility complex-dependent susceptibility; substantial similarities in neuropathology, including axonal damage and remyelination; and paucity of T-cell apoptosis in demyelinating disease. Both diseases are immunologically mediated. These common features emphasize the close similarities of Theiler's virus-induced demyelinating disease in mice and MS in humans.


Assuntos
Infecções por Cardiovirus/fisiopatologia , Esclerose Múltipla/fisiopatologia , Theilovirus/patogenicidade , Animais , Infecções por Cardiovirus/imunologia , Infecções por Cardiovirus/metabolismo , Modelos Animais de Doenças , Humanos , Modelos Imunológicos , Esclerose Múltipla/imunologia , Esclerose Múltipla/metabolismo
17.
Clin Diagn Lab Immunol ; 11(1): 195-202, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14715568

RESUMO

Osteoarthritis (OA) is a heterogeneous disease which rheumatologists consider to be noninflammatory. However, recent studies suggest that, at least in certain patients, OA is an inflammatory disease and that patients often exhibit inflammatory infiltrates in the synovial membranes (SMs) of macrophages and activated T cells expressing proinflammatory cytokines. We report here that the expression of CD3zeta is significantly decreased in T cells infiltrating the SMs of patients with OA. The CD3zeta chain is involved in the T-cell signal transduction cascade, which is initiated by the engagement of the T-cell antigen receptor and which culminates in T-cell activation. Double immunofluorescence of single-cell suspensions derived from the SMs from nine patients with OA revealed significantly increased proportions of CD3epsilon-positive (CD3epsilon+) cells compared with the proportions of CD3zeta-positive (CD3zeta+) T cells (means +/- standard errors of the means, 80.48% +/- 3.92% and 69.02% +/- 6.51%, respectively; P = 0.0096), whereas there were no differences in the proportions of these cells in peripheral blood mononuclear cells (PBMCs) from healthy donors (94.73% +/- 1.39% and 93.79% +/- 1.08%, respectively; not significant). The CD3zeta+ cell/CD3epsilon+ cell ratio was also significantly decreased for T cells from the SMs of patients with OA compared with that for T cells from the PBMCs of healthy donors (0.84 +/- 0.17 and 0.99 +/- 0.01, respectively; P = 0.0302). The proportions of CD3epsilon+ CD3zeta+ cells were lower in the SMs of patients with OA than in the PBMCs of healthy donors (65.04% +/- 6.7% and 90.81% +/- 1.99%, respectively; P = 0.0047). Substantial proportions (about 15%) of CD3epsilon+ CD3zeta-negative (CD3zeta-) and CD3epsilon-negative (CD3epsilon-) CD3zeta- cells were found in the SMs of patients with OA. Amplification of the CD3zeta and CD3delta transcripts from the SMs of patients with OA by reverse transcriptase PCR consistently exhibited stronger bands for CD3delta cDNA than for CD3zeta cDNA The CD3zeta/CD3delta transcript ratio in the SMs of patients with OA was significantly lower than that in PBMCs from healthy controls (P < 0.0001). These results were confirmed by competitive MIMIC PCR. Immunoreactivities for the CD3zeta protein were detected in the SMs of 10 of 19 patients with OA, and they were of various intensities, whereas SMs from all patients were CD3epsilon+ (P = 0.0023). The decreased expression of the CD3zeta transcript and protein in T cells from the SMs of patients with OA relative to that of the CD3epsilon transcript is suggestive of chronic T-cell stimulation and supports the concept of T-cell involvement in OA.


Assuntos
Complexo CD3/metabolismo , Osteoartrite/imunologia , Osteoartrite/patologia , Membrana Sinovial/imunologia , Membrana Sinovial/patologia , Linfócitos T/imunologia , Linfócitos T/patologia , Adulto , Idoso , Complexo CD3/genética , DNA Complementar/genética , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Osteoartrite/genética
18.
Cell Immunol ; 225(2): 75-90, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14698142

RESUMO

Chronic cardiac allograft rejection is characterized by graft arteriopathy and is a major obstacle of graft survival. We investigated T-cell receptor (TCR) alpha-chain transcripts of T cells infiltrating human epicardial coronary arteries from cardiac allografts with chronic rejection. The non-palindromic adaptor-polymerase chain reaction (NPA-PCR) was used to specifically amplify TCR alpha-chain transcripts from five explanted cardiac allografts with chronic rejection. The amplified products were cloned and sequenced to obtain the entire ValphaJalpha region. Immuno-histochemistry was used to identify the mononuclear cell infiltrates in the coronary arteries. All the five coronary artery specimens exhibited large populations of infiltrating mononuclear cells, which were primarily comprised of T cells and macrophages. In three specimens, high proportions ( approximately 80%) of identical alpha-chain TCR transcripts were detected. In peripheral blood mononuclear cells from a healthy individual, alpha-chain TCR transcripts were unique when compared to each other. Endomyocardial biopsies collected from one patient six months before the allograft was explanted, contained identical alpha-chain TCR transcripts to those found to be clonally expanded in the coronary arteries from this patient. These results indicate that T cells infiltrating the epicardial arteries of cardiac allografts with chronic rejection undergo proliferation and clonal expansion in response to a specific antigen, which very likely is an (allo)antigen(s).


Assuntos
Vasos Coronários/imunologia , Rejeição de Enxerto/imunologia , Transplante de Coração , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/metabolismo , Movimento Celular/imunologia , Vasos Coronários/patologia , Variação Genética , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Receptores de Antígenos de Linfócitos T/biossíntese , Linfócitos T/imunologia , Linfócitos T/patologia , Transplante Homólogo
19.
Virology ; 315(1): 110-23, 2003 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-14592764

RESUMO

Theiler murine encephalomyelitis virus (TMEV), DA strain, induces in susceptible strain of mice a biphasic disease consisting of early acute disease followed by late chronic demyelinating disease. Both phases of the disease are associated with inflammatory infiltrates of the central nervous system (CNS). Late chronic demyelinating disease induced by TMEV serves as an excellent model to study human demyelinating disease, multiple sclerosis. During early acute disease, the virus is partially cleared from the CNS by CD3(+) T cells. These T cells express Fas, FasL, negligible levels of Bcl-2 proteins and undergo activation-induced cell death as determined by TUNEL assay leading to resolution of the inflammatory response. In contrast, during late chronic demyelinating disease, and despite dense perivascular and leptomeningeal infiltrates, only very few cells undergo apoptosis. Mononuclear cells infiltrating the CNS express Bcl-2. It appears that the lack of apoptosis of T cells during late chronic demyelinating disease leads to the accumulation of these cells in the CNS. These cells may play a role in the pathogenesis of the demyelinating disease.


Assuntos
Apoptose , Complexo CD3/metabolismo , Sistema Nervoso Central/imunologia , Ativação Linfocitária , Linfócitos T/imunologia , Theilovirus/imunologia , Doença Aguda , Animais , Infecções por Cardiovirus/imunologia , Infecções por Cardiovirus/virologia , Sistema Nervoso Central/virologia , Doença Crônica , Modelos Animais de Doenças , Proteína Ligante Fas , Feminino , Imuno-Histoquímica , Glicoproteínas de Membrana/metabolismo , Camundongos , Esclerose Múltipla , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptor fas/metabolismo
20.
Anticancer Res ; 23(3A): 1969-96, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12894571

RESUMO

Strong evidence has been accumulated demonstrating that tumor cells in humans and animal are recognized in general as non-self by the immune system and they are able to induce an immune response which often leads to their elimination. In humans, this evidence includes: (a) The development of T-cell lines and clones with antitumor activity (cytotoxic or helper) which is restricted to autologous tumor cells or to cells expressing the same tumor peptide/HLA epitope; (b) the presence of oligoclonal T cells infiltrating many tumors; (c) the identification and molecular cloning of tumor antigens and of peptides derived from these antigens, which elicit HLA-restricted immune responses. Their discovery provided the ultimate proof for the presence of specific immune responses in human tumors. The availability for the first time of molecularly cloned tumor antigens permitted the development of peptide or recombinant tumor vaccines. Although significant progress has been made and tumor peptide vaccines capable of eliciting biological responses in more than 50% of the patients and objective clinical responses in 10 to 42% of the patients have been reported, certain major problems remain and need to be resolved in order to develop effective tumor vaccines. These problems emanate from the following mechanisms that the tumor cells are employing to avoid detection and destruction by the immune system: (i) Down-regulation of HLA class I expression on the surface of tumor cells; (ii) Down-regulation of tumor antigen expression or selection of negative tumor variants; (iii) Expression of naturally occurring altered peptide ligands by tumor cells; (iv) Lack of costimulatory molecules on tumors cells; (v) Production of immunosuppressive cytokines, such as TGF-beta and IL-10; (vi) Induction of lymphocyte apoptosis by tumor cells using the Fas/Fas L pathway; (vii) Down-regulation or absence of CD3 zeta (zeta) transcripts or protein in tumor-infiltrating lymphocytes (TIL), and others. The selection of optimal tumor antigens for vaccine development is another issue that requires attention. Lineage specific or differentiation antigens appear to be better candidates for the development of tumor vaccines because they are expressed in all tumor cells. Methods for antigen presentation, such as those using dendritic cells, also play a critical role in the development of tumor vaccines. In addition to the progress towards the development of tumor vaccines, substantial progress has been made in developing advanced methods of adoptive immunotherapy based on TIL. This approach can be effective when an immune response can not be elicited in vivo. The progress made towards the development of tumor vaccines and approaches for adoptive immunotherapy has been substantial. Additional studies need to be carried out to develop new and effective tumor vaccines and adoptive immunotherapy methods.


Assuntos
Vacinas Anticâncer/imunologia , Neoplasias/imunologia , Animais , Humanos , Imunoterapia Ativa/métodos
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