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2.
Eur J Immunol ; 45(7): 1991-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25847325

RESUMO

Oral tolerance is the antigen-specific inhibition of a systemic immune response after oral antigen uptake and well established in animal models. We recently showed that keyhole limpet hemocyanin (KLH) feeding modulates subsequently induced systemic immune responses in humans as well. In the present study, we investigated whether oral KLH can also modulate preexisting antigen-specific systemic B- and T-cell responses. We induced delayed-type hypersensitivity (DTH) reactions as well as systemic KLH-specific B- and T-cell responses by subcutaneous KLH injections. Subsequent oral KLH administration decreased the small proportion of antigen-specific CD4(+) T cells positive for the cytokine IL-17 at the end of the feeding regimen even further. After reimmunization, there was no difference in DTH reactions and the KLH-specific B-cell responses, but KLH-fed volunteers had an increased proportion of antigen-specific CD4(+) T cells positive for IL-10 and a reduced proportion of antigen-specific CD4(+) T cells positive for the skin-homing receptor cutaneous lymphocyte antigen and IL-2 and IFN-γ. Taken together, oral KLH can modulate a preexisting systemic KLH-specific immune response. These results suggest that feeding antigen may offer therapeutic strategies for the suppression of unwanted immune reactions in humans.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Linfócitos T CD4-Positivos/imunologia , Hemocianinas/administração & dosagem , Tolerância Imunológica/imunologia , Administração Oral , Adulto , Dessensibilização Imunológica/métodos , Feminino , Citometria de Fluxo , Hemocianinas/imunologia , Humanos , Hipersensibilidade Tardia/imunologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
3.
Immunology ; 139(1): 100-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23278129

RESUMO

Plasmacytoid dendritic cells (pDC) in mesenteric lymph nodes (MLN) may be important regulators of both inflammatory and non-inflammatory mucosal immune responses but human studies are rare. Here we compare pDC from human MLN and peripheral blood (PB) by phenotype and function. MLN from patients with or without inflammatory bowel disease (IBD) undergoing colon surgery and PB from patients with IBD and from controls were used to isolate mononuclear cells. The pDC were analysed by flow cytometry for the expression of CD40, CD80, CD83, CD86, CCR6, CCR7, CX3CR1, CD103 and HLA-DR. Purified pDC from MLN and PB were stimulated with staphylococcus enterotoxin B (SEB), CpG-A, interleukin-3 (IL-3), SEB + IL-3, CpG-A + IL-3 or left unstimulated, and cultured alone or with purified allogeneic CD4(+) CD45RA(+) HLA-DR- T cells. Subsequently, concentrations of IL-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-17, interferon-α (IFN-α), IFN-γ and tumour necrosis factor-α (TNF-α) in culture supernatants were determined by multiplex bead array. The PB pDC from IBD patients exhibited an activated and matured phenotype whereas MLN pDC and control PB pDC were less activated. CpG-A and CpG-A + IL-3-stimulated MLN pDC secreted less IL-6 and TNF-α compared with PB pDC from controls. Compared with co-cultures of naive CD4 T cells with PB pDC, co-cultures with MLN pDC contained more IL-2, IL-10 and IFN-γ when stimulated with SEB and SEB + IL-3, and less IFN-α when stimulated with CpG-A. MLN pDC differ phenotypically from PB pDC and their pattern of cytokine secretion and may contribute to specific outcomes of mucosal immune reactions.


Assuntos
Células Dendríticas/imunologia , Imunidade nas Mucosas , Doenças Inflamatórias Intestinais/imunologia , Linfonodos/imunologia , Mesentério/imunologia , Plasmócitos/imunologia , Idoso , Antígenos CD/imunologia , Antígenos CD/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Técnicas de Cocultura , Citocinas/imunologia , Citocinas/metabolismo , Citocinas/farmacologia , Células Dendríticas/metabolismo , Células Dendríticas/patologia , Enterotoxinas/farmacologia , Feminino , Humanos , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Linfonodos/metabolismo , Linfonodos/patologia , Masculino , Mesentério/metabolismo , Mesentério/patologia , Pessoa de Meia-Idade , Oligodesoxirribonucleotídeos/farmacologia , Plasmócitos/metabolismo , Plasmócitos/patologia
4.
Arthritis Res Ther ; 12(6): R204, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21050432

RESUMO

INTRODUCTION: Epratuzumab, a humanized anti-CD22 monoclonal antibody, is under investigation as a therapeutic antibody in non-Hodgkin's lymphoma and systemic lupus erythematosus (SLE), but its mechanism of action on B-cells remains elusive. Treatment of SLE patients with epratuzumab leads to a reduction of circulating CD27(negative) B-cells, although epratuzumab is weakly cytotoxic to B-cells in vitro. Therefore, potential effects of epratuzumab on adhesion molecule expression and the migration of B-cells have been evaluated. METHODS: Epratuzumab binding specificity and the surface expression of adhesion molecules (CD62L, ß7 integrin and ß1 integrin) after culture with epratuzumab was studied on B-cell subsets of SLE patients by flow cytometry. In addition, in vitro transwell migration assays were performed to analyze the effects of epratuzumab on migration towards different chemokines such as CXCL12, CXCL13 or to CXCR3 ligands, and to assess the functional consequences of altered adhesion molecule expression. RESULTS: Epratuzumab binding was considerably higher on B-cells relative to other cell types assessed. No binding of epratuzumab was observed on T-cells, while weak non-specific binding of epratuzumab on monocytes was noted. On B-cells, binding of epratuzumab was particularly enhanced on CD27(negative) B-cells compared to CD27(positive) B-cells, primarily related to a higher expression of CD22 on CD27(negative) B-cells. Moreover, epratuzumab binding led to a decrease in the cell surface expression of CD62L and ß7 integrin, while the expression of ß1 integrin was enhanced. The effects on the pattern of adhesion molecule expression observed with epratuzumab were principally confined to a fraction of the CD27(negative) B-cell subpopulation and were associated with enhanced spontaneous migration of B-cells. Furthermore, epratuzumab also enhanced the migration of CD27(negative) B-cells towards the chemokine CXCL12. CONCLUSIONS: The current data suggest that epratuzumab has effects on the expression of the adhesion molecules CD62L, ß7 integrin and ß1 integrin as well as on migration towards CXCL12, primarily of CD27(negative) B-cells. Therefore, induced changes in migration appear to be part of the mechanism of action of epratuzumab and are consistent with the observation that CD27(negative) B-cells were found to be preferentially reduced in the peripheral blood under treatment.


Assuntos
Anticorpos Monoclonais/farmacologia , Linfócitos B/efeitos dos fármacos , Moléculas de Adesão Celular/efeitos dos fármacos , Movimento Celular , Quimiotaxia de Leucócito/efeitos dos fármacos , Lúpus Eritematoso Sistêmico/metabolismo , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Adulto , Anticorpos Monoclonais Humanizados , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Moléculas de Adesão Celular/biossíntese , Moléculas de Adesão Celular/imunologia , Separação Celular , Feminino , Citometria de Fluxo , Humanos , Cadeias beta de Integrinas/biossíntese , Integrina beta1/biossíntese , Selectina L/biossíntese , Lúpus Eritematoso Sistêmico/imunologia , Masculino
5.
Eur J Immunol ; 40(11): 3128-37, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20957752

RESUMO

Oral antigen uptake can induce systemic immune responses ranging from tolerance to immunity. However, the underlying mechanisms are poorly understood, especially in humans. Here, keyhole limpet hemocyanin (KLH), a neoantigen which has been used in earlier studies of oral tolerance, was fed in a repeated low-dose and a single high-dose protocol to healthy volunteers. KLH-specific CD4(+) T-cell proliferation and cytokine production, as well as KLH-specific serum Ab and the effects of oral KLH on a subsequent parenterally induced systemic immune response, were analyzed. Repeated low-dose oral KLH alone induced antigen-specific CD4(+) T cells positive predominantly for the gut-homing receptor integrin ß7 and the cytokines IL-2 and TNF-α; some CD4(+) T cells also produced IL-4. Oral feeding of KLH accelerated a subsequent parenterally induced systemic CD4(+) T-cell response. The cytokine pattern of KLH-specific CD4(+) T cells shifted toward more IL-4- and IL-10- and less IFN-γ-, IL-2- and TNF-α-producing cells. The parenterally induced systemic KLH-specific B-cell response was accelerated and amplified by oral KLH. The impact of single high-dose oral KLH on antigen-specific immune responses was less pronounced compared with repeated low-dose oral KLH. These findings suggest that oral antigen can effectively modulate subsequently induced systemic antigen-specific immune responses. Immunomodulation by oral antigen may offer new therapeutic strategies for Th type1-mediated inflammatory diseases and for the development of vaccination strategies.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Linfócitos B/imunologia , Proliferação de Células/efeitos dos fármacos , Hemocianinas/administração & dosagem , Hemocianinas/imunologia , Células Th1/imunologia , Administração Oral , Adulto , Citocinas/imunologia , Relação Dose-Resposta Imunológica , Humanos , Cadeias beta de Integrinas/imunologia , Masculino , Pessoa de Meia-Idade , Vacinação
6.
J Trauma ; 64(3): 586-96; discussion 596-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18332797

RESUMO

BACKGROUND: Recent data suggest that ubiquitin (Ub) is systemically released after trauma, has pleiotropic effects on host defense mechanisms, and that Ub administration reduces fluid shifts into tissues during inflammation. Ub release after burns (B) has not been studied and its association with injury severity and outcome after blunt trauma (T) is unknown. Thus, we evaluated Ubs association with injury severity and outcomes after B and T. METHODS: Injury severity was assessed with the Injury Severity Score (ISS) in T and burn size (% total body surface area, %TBSA) in B. A total of 129 T (ISS: 26 +/- 13) and 55 B (46% +/- 18% TBSA) were observed for sepsis/multiple organ failure (MOF) and survival. In B, sequential organ failure assessment scores were documented daily. Fifty volunteers served as controls (C) Ub serum levels were measured on day 0 (admission), 1, 3, 5, and 7 by enzyme-linked immunosorbent assay. Data were analyzed using bivariate or partial correlation analyses, t test, and analysis of variance with Tukey post-hoc test for multiple comparisons (two-tailed p < 0.05). RESULTS: Ub was significantly elevated in patients. Peak levels (ng/mL) were detectable on day 0 (C: 118 +/- 76; T: 359 +/- 205; B: 573 +/- 331) and increased with increased ISS, %TBSA, and presence of inhalation injury. In T, Ub normalized by day 3, but remained elevated in B. In B, Ub correlated significantly negative with sequential organ failure assessment scores (r: -0.143; p = 0.0147), sepsis/MOF development (r: -0.363; p = 0.001), and survival (r: -0.231; p = 0.009). Compared with B who recovered uneventfully, Ub levels were significantly lower on days 1 to 7 and on days 5/7 in B who developed sepsis/MOF or died, respectively. CONCLUSION: Ub concentrations reflect the extent of tissue damage. Along with Ubs previously described anti- inflammatory properties, this study suggests that its systemic release is protective, that burn patients who develop sepsis/MOF have a relative Ub deficiency and that Ub could play an important role during the physiologic response to burn injury.


Assuntos
Queimaduras/sangue , Ubiquitina/sangue , Ferimentos não Penetrantes/sangue , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/sangue , Sepse/sangue , Ferimentos não Penetrantes/complicações
7.
J Orthop Res ; 26(7): 999-1006, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18302283

RESUMO

Post-traumatic disc degeneration with consecutive loss of reduction and kyphosis remains a debatable issue within both the operative and nonoperative treatment regimen of thoracolumbar spine fractures. Intervertebral disc (IVD) cell apoptosis has been suggested to play a vital role in promoting the degeneration process. To evaluate and compare apoptosis-regulating signaling mechanisms, IVDs were obtained from patients with thoracolumbar spine fractures (n = 21), patients suffering from symptomatic IVD degeneration (n = 6), and from patients undergoing surgical resection of a primary vertebral tumor (n = 3 used as control samples). All tissues were prospectively analyzed in regards to caspase-3/7, -8, and -9 activity, apoptosis-receptor expression levels, and gene expression of the mitochondria-bound apoptosis-regulating proteins Bax and Bcl-2. Morphologic changes characteristic for apoptotic cell death were confirmed by H&E staining. Statistical significance was designated at p < 0.05 using the Student's t-test. Both traumatic and degenerative IVD demonstrated a significant increase of caspase-3/7 activity with evident apoptosis. Although caspase-3/7 activation was significantly greater in degenerated discs, both showed equally significant activation of the initiator caspases 8 and 9. Traumatic IVD alone demonstrated a significant increase of the Fas receptor (FasR), whereas the TNF receptor I (TNFR I) was equally up-regulated in both morbid IVD groups. Only traumatic IVD showed distinct changes in up-regulated TNF expression, in addition to significantly down-regulated antiapoptotic Bcl-2 protein. Our results suggest that post-traumatic disc changes may be promoted and amplified by both the intrinsic mitochondria-mediated and extrinsic receptor-mediated apoptosis signaling pathways, which could be, in part, one possible explanation for developing subsequent disc degeneration.


Assuntos
Apoptose/fisiologia , Disco Intervertebral/metabolismo , Vértebras Lombares/lesões , Doenças da Coluna Vertebral/metabolismo , Fraturas da Coluna Vertebral/metabolismo , Vértebras Torácicas/lesões , Adulto , Idoso , Caspases/metabolismo , Regulação para Baixo , Feminino , Humanos , Disco Intervertebral/enzimologia , Disco Intervertebral/fisiopatologia , Masculino , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/fisiologia , Receptor fas/metabolismo
8.
Crit Care ; 12(1): R8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18211685

RESUMO

INTRODUCTION: The innate immune response to trauma hemorrhage involves inflammatory mediators, thus promoting cellular dysfunction as well as cell death in diverse tissues. These effects ultimately bear the risk of post-traumatic complications such as organ dysfunction, multiple organ failure, or adult respiratory distress syndrome. In this study, a murine model of resuscitated hemorrhagic shock (HS) was used to determine the apoptosis in spleen as a marker of cellular injury and reduced immune functions. METHODS: Male C57BL-6 mice were subjected to sham operation or resuscitated HS. At t = 0 hours, t = 24 hours, and t = 72 hours, mice were euthanized and the spleens were removed and evaluated for apoptotic changes via DNA fragmentation, caspase activities, and activation of both extrinsic and intrinsic apoptotic pathways. Spleens from untreated mice were used as control samples. RESULTS: HS was associated with distinct lymphocytopenia as early as t = 0 hours after hemorrhage without regaining baseline levels within the consecutive 72 hours when compared with sham and control groups. A rapid activation of splenic apoptosis in HS mice was observed at t = 0 hours and t = 72 hours after hemorrhage and predominantly confirmed by increased DNA fragmentation, elevated caspase-3/7, caspase-8, and caspase-9 activities, and enhanced expression of intrinsic mitochondrial proteins. Accordingly, mitochondrial pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins were inversely expressed within the 72-hour observation period, thereby supporting significant pro-apoptotic changes. Solely at t = 24 hours, expression of the anti-apoptotic Mcl-1 protein shows a significant increase when compared with sham-operated and control animals. Furthermore, expression of extrinsic death receptors were only slightly increased. CONCLUSION: Our data suggest that HS induces apoptotic changes in spleen through a biphasic caspase-dependent mechanism and imply a detrimental imbalance of pro- and anti-apoptotic mitochondrial proteins Bax, Bcl-2, and Mcl-1, thereby promoting post-traumatic immunosuppression.


Assuntos
Apoptose/fisiologia , Fragmentação do DNA , Genes bcl-2/fisiologia , Proteínas de Neoplasias/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Choque Hemorrágico/fisiopatologia , Baço/fisiologia , Proteína X Associada a bcl-2/fisiologia , Animais , Caspases/metabolismo , Contagem de Células , Linfopenia/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína de Sequência 1 de Leucemia de Células Mieloides , Ressuscitação , Choque Hemorrágico/complicações , Choque Hemorrágico/imunologia , Baço/enzimologia , Baço/metabolismo
9.
J Trauma ; 62(6): 1396-403; discussion 1403-4, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17563655

RESUMO

BACKGROUND: Today's management of patients with multiple injuries remains controversial with regard to damage control and the appropriate timing of operative treatment ("second hit"). Among the multitude of physiologic parameters critical to the immune defense and clinical course of recovery, recent research has proven the regulation of distinct pro- and anti-inflammatory mediators to be closely associated with posttraumatic outcome and complications, including systemic inflammatory response syndrome (SIRS) and sepsis. This study sought to investigate the significance of multiple injuries and consecutive operative treatment ("second hit") with regard to the early inflammatory profile and its importance within the host's immune function. METHODS: Peripheral whole blood was obtained from 32 patients with multiple injuries (injury severity score [ISS] >20) and 14 healthy control subjects on the day of injury (day 0) and 24 hours thereafter (day 1). Trauma patients were divided into two groups (trauma versus trauma + immediate operation ["second hit"]). Whole blood was centrifuged at 400 g at room temperature for subsequent plasma collection and analyses of Interleukin-6 (IL-6), IL-10 and soluble triggering receptor expressed on myeloid cells (sTREM)-1 plasma concentrations by enzyme-linked immunosorbent assay, respectively. RESULTS: IL-6 plasma levels from second hit trauma patients (n = 18, ISS 35.5 +/- 12.2) significantly exceeded values determined in both trauma patients without a second hit (n = 14, ISS 30.5 +/- 5.3) and healthy control subjects (n = 14) by posttrauma day 1 (p < 0.05). IL-10 plasma concentrations on day 1 were equally and significantly elevated in both trauma patient populations, when compared with control samples (p < 0.05). In contrast, sTREM-1 was exclusively increased in trauma patients with a second hit, suggesting a strong proinflammatory response in patients with multiple injuries challenged with immediate surgical care (p < 0.05). CONCLUSION: Immediate surgical treatment of patients with multiple injuries augments the proinflammatory immune response in the early phase of recovery as determined by increased IL-6 and sTREM-1 plasma levels. If not required solely for damage control, the early second hit from additional surgical stress might promote posttraumatic complications by surcharging the innate immune response to injury.


Assuntos
Imunidade Inata/imunologia , Inflamação/imunologia , Traumatismo Múltiplo/imunologia , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Feminino , Humanos , Inflamação/etiologia , Interleucina-10/sangue , Interleucina-6/sangue , Masculino , Glicoproteínas de Membrana/sangue , Pessoa de Meia-Idade , Traumatismo Múltiplo/sangue , Receptores Imunológicos/sangue , Receptor Gatilho 1 Expresso em Células Mieloides
10.
J Trauma ; 61(5): 1285-91, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17099548

RESUMO

Posttraumatic anemia in multiply injured patients is caused by hemorrhage, reduced red blood cell survival, and impaired erythropoiesis. Trauma-induced hyperinflammation causes impaired bone-marrow function by means of blunted erythropoietin (EPO) response, reduced iron availability, suppression and egress of erythroid progenitor cells. To treat posttraumatic anemia in severely injured patients, symptomatic therapy by blood transfusion is not sufficient. Furthermore, EPO, iron, and the use of red cell substitutes should be considered. The posttraumatic systemic inflammatory response syndrome (SIRS) induces posttraumatic anemia. Thus, a worsening of SIRS by a "second-hit" through blood transfusion ought to be avoided.


Assuntos
Anemia/etiologia , Eritropoese/fisiologia , Ferro/fisiologia , Traumatismo Múltiplo/fisiopatologia , Transfusão de Eritrócitos , Eritrócitos/patologia , Hidratação , Hemorragia/complicações , Humanos , Deficiências de Ferro , Ressuscitação/métodos , Síndrome de Resposta Inflamatória Sistêmica/fisiopatologia
11.
BMC Clin Pathol ; 6: 5, 2006 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-16719914

RESUMO

BACKGROUND: Vertebral fractures resulting from high energy trauma often comprise the risk of posttraumatic degenerative changes in the affected intervertebral discs (IVD). Particularly in conservatively treated patients, or in cases after implant removal of an exclusively posterior stabilization, consecutive disc degeneration and the associated functional losing of the spinal segment clearly represent detrimental treatment results. In this regard, apoptosis of IVD cells has been suggested to be involved in the critical changes of the extracellular matrix. METHODS: To investigate whether fractures of the vertebrae induce apoptosis in the affected IVD, disc tissue from patients (n = 17) undergoing open reduction and internal fixation of thoracolumbar spine fractures were analysed in regards to caspase activity, apoptosis-receptor expression levels and gene expression of apoptosis-regulating proteins such as Bax and Bcl-2. Healthy IVD tissue (n = 3) obtained from patients undergoing surgical resection of adjacent vertebrae were used as control samples. RESULTS: In contrast to healthy control IVD tissues, samples from traumatic thoracolumbar IVD showed positive TUNEL staining and a significant increase of caspase-3/7 activity. Interestingly, analyses of the initiator caspase-8 and -9 revealed significantly increased activation levels compared to control values, suggesting the coexistent activation of both the extrinsic (receptor-mediated) and intrinsic (mitochondria-mediated) apoptosis pathway. Accordingly, expression levels of the Fas receptor (FasR) mRNA were significantly increased. Although the TNF receptor I (TNFR I) was only slightly upregulated, corresponding TNFalpha from trauma IVD presented significantly increased mRNA expression values. Furthermore, traumatic IVD cells demonstrated significantly reduced expression of the mitochondria-bound anti-apoptotic Bcl-2, thereby maintaining baseline transcriptional levels of the pro-apoptotic Bax protein when compared to control IVD cells. CONCLUSION: Our data suggest that thoracolumbar fractures induce early caspase-dependent apoptosis in IVD cells of the affected intervertebral disc, in part, by downregulation of the anti-apoptotic protein Bcl-2 (intrinsic apoptosis pathway), as well as signalling via the death receptor complex (TNFR I and FasR).

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