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1.
J Immunol ; 201(7): 1907-1917, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30127089

RESUMO

In both NOD mice and humans, the development of type 1 diabetes (T1D) is dependent in part on autoreactive CD8+ T cells recognizing pancreatic ß cell peptides presented by often quite common MHC class I variants. Studies in NOD mice previously revealed that the common H2-Kd and/or H2-Db class I molecules expressed by this strain aberrantly lose the ability to mediate the thymic deletion of pathogenic CD8+ T cell responses through interactions with T1D susceptibility genes outside the MHC. A gene(s) mapping to proximal chromosome 7 was previously shown to be an important contributor to the failure of the common class I molecules expressed by NOD mice to mediate the normal thymic negative selection of diabetogenic CD8+ T cells. Using an inducible model of thymic negative selection and mRNA transcript analyses, we initially identified an elevated Nfkbid expression variant as a likely NOD-proximal chromosome 7 region gene contributing to impaired thymic deletion of diabetogenic CD8+ T cells. CRISPR/Cas9-mediated genetic attenuation of Nfkbid expression in NOD mice resulted in improved negative selection of autoreactive diabetogenic AI4 and NY8.3 CD8+ T cells. These results indicated that allelic variants of Nfkbid contribute to the efficiency of intrathymic deletion of diabetogenic CD8+ T cells. However, although enhancing thymic deletion of pathogenic CD8+ T cells, ablating Nfkbid expression surprisingly accelerated T1D onset that was associated with numeric decreases in both regulatory T and B lymphocytes in NOD mice.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Cromossomos Humanos Par 7/genética , Diabetes Mellitus Tipo 1/imunologia , Proteínas I-kappa B/genética , Timo/imunologia , Alelos , Animais , Autoantígenos/imunologia , Diferenciação Celular , Células Cultivadas , Deleção Clonal , Modelos Animais de Doenças , Suscetibilidade a Doenças , Humanos , Proteínas I-kappa B/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Polimorfismo Genético
2.
J Immunol ; 200(10): 3353-3363, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29632144

RESUMO

Type 1 diabetes (T1D) is characterized by T cell-mediated destruction of the insulin-producing ß cells of the pancreatic islets. Among the loci associated with T1D risk, those most predisposing are found in the MHC region. HLA-B*39:06 is the most predisposing class I MHC allele and is associated with an early age of onset. To establish an NOD mouse model for the study of HLA-B*39:06, we expressed it in the absence of murine class I MHC. HLA-B*39:06 was able to mediate the development of CD8 T cells, support lymphocytic infiltration of the islets, and confer T1D susceptibility. Because reduced thymic insulin expression is associated with impaired immunological tolerance to insulin and increased T1D risk in patients, we incorporated this in our model as well, finding that HLA-B*39:06-transgenic NOD mice with reduced thymic insulin expression have an earlier age of disease onset and a higher overall prevalence as compared with littermates with typical thymic insulin expression. This was despite virtually indistinguishable blood insulin levels, T cell subset percentages, and TCR Vß family usage, confirming that reduced thymic insulin expression does not impact T cell development on a global scale. Rather, it will facilitate the thymic escape of insulin-reactive HLA-B*39:06-restricted T cells, which participate in ß cell destruction. We also found that in mice expressing either HLA-B*39:06 or HLA-A*02:01 in the absence of murine class I MHC, HLA transgene identity alters TCR Vß usage by CD8 T cells, demonstrating that some TCR Vß families have a preference for particular class I MHC alleles.


Assuntos
Diabetes Mellitus Tipo 1/genética , Antígenos HLA-B/genética , Insulina/genética , Timo/metabolismo , Alelos , Animais , Linfócitos T CD8-Positivos/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Modelos Animais de Doenças , Genes MHC Classe I/genética , Antígeno HLA-A2/genética , Células Secretoras de Insulina/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos
3.
Proc Natl Acad Sci U S A ; 115(10): E2329-E2337, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29463744

RESUMO

Autoimmune type 1 diabetes (T1D) and other autoimmune diseases are associated with particular MHC haplotypes and expansion of autoreactive T cells. Induction of MHC-mismatched but not -matched mixed chimerism by hematopoietic cell transplantation effectively reverses autoimmunity in diabetic nonobese diabetic (NOD) mice, even those with established diabetes. As expected, MHC-mismatched mixed chimerism mediates deletion in the thymus of host-type autoreactive T cells that have T-cell receptor (TCR) recognizing (cross-reacting with) donor-type antigen presenting cells (APCs), which have come to reside in the thymus. However, how MHC-mismatched mixed chimerism tolerizes host autoreactive T cells that recognize only self-MHC-peptide complexes remains unknown. Here, using NOD.Rag1-/-BDC2.5 or NOD.Rag1-/-BDC12-4.1 mice that have only noncross-reactive transgenic autoreactive T cells, we show that induction of MHC-mismatched but not -matched mixed chimerism restores immune tolerance of peripheral noncross-reactive autoreactive T cells. MHC-mismatched mixed chimerism results in increased percentages of both donor- and host-type Foxp3+ Treg cells and up-regulated expression of programmed death-ligand 1 (PD-L1) by host-type plasmacytoid dendritic cells (pDCs). Furthermore, adoptive transfer experiments showed that engraftment of donor-type dendritic cells (DCs) and expansion of donor-type Treg cells are required for tolerizing the noncross-reactive autoreactive T cells in the periphery, which are in association with up-regulation of host-type DC expression of PD-L1 and increased percentage of host-type Treg cells. Thus, induction of MHC-mismatched mixed chimerism may establish a peripheral tolerogenic DC and Treg network that actively tolerizes autoreactive T cells, even those with no TCR recognition of the donor APCs.


Assuntos
Diabetes Mellitus Tipo 1/genética , Complexo Principal de Histocompatibilidade , Tolerância Periférica , Linfócitos T/imunologia , Animais , Autoimunidade , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/terapia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/transplante , Quimeras de Transplante/genética
4.
Diabetes ; 67(5): 923-935, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29472249

RESUMO

Improved mouse models for type 1 diabetes (T1D) therapy development are needed. T1D susceptibility is restored to normally resistant NOD.ß2m-/- mice transgenically expressing human disease-associated HLA-A*02:01 or HLA-B*39:06 class I molecules in place of their murine counterparts. T1D is dependent on pathogenic CD8+ T-cell responses mediated by these human class I variants. NOD.ß2m-/--A2.1 mice were previously used to identify ß-cell autoantigens presented by this human class I variant to pathogenic CD8+ T cells and for testing therapies to attenuate such effectors. However, NOD.ß2m-/- mice also lack nonclassical MHC I family members, including FcRn, required for antigen presentation, and maintenance of serum IgG and albumin, precluding therapies dependent on these molecules. Hence, we used CRISPR/Cas9 to directly ablate the NOD H2-Kd and H2-Db classical class I variants either individually or in tandem (cMHCI-/-). Ablation of the H2-Ag7 class II variant in the latter stock created NOD mice totally lacking in classical murine MHC expression (cMHCI/II-/-). NOD-cMHCI-/- mice retained nonclassical MHC I molecule expression and FcRn activity. Transgenic expression of HLA-A2 or -B39 restored pathogenic CD8+ T-cell development and T1D susceptibility to NOD-cMHCI-/- mice. These next-generation HLA-humanized NOD models may provide improved platforms for T1D therapy development.


Assuntos
Diabetes Mellitus Tipo 1/genética , Modelos Animais de Doenças , Antígeno HLA-A2/genética , Antígenos HLA-B/genética , Camundongos , Microglobulina beta-2/genética , Animais , Sistemas CRISPR-Cas , Diabetes Mellitus Tipo 1/terapia , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos Transgênicos
5.
J Immunol ; 199(11): 3757-3770, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29055002

RESUMO

In NOD mice and also likely humans, B lymphocytes play an important role as APC-expanding autoreactive T cell responses ultimately causing type 1 diabetes (T1D). Currently, humans at high future T1D risk can only be identified at late prodromal stages of disease indicated by markers such as insulin autoantibodies. When commenced in already insulin autoantibody+ NOD mice, continuous BAFFR-Fc treatment alone or in combination with anti-CD20 (designated combo therapy) inhibited T1D development. Despite eliciting broader B lymphocyte depletion, continuous combo therapy afforded no greater T1D protection than did BAFFR-Fc alone. As previously observed, late disease stage-initiated anti-CD20 monotherapy did not inhibit T1D, and in this study was additionally found to be associated with development of drug-blocking Abs. Promisingly, NOD mice given transient late disease stage BAFFR-Fc monotherapy were rendered T1D resistant. However, combo treatment abrogated the protective effect of transient BAFFR-Fc monotherapy. NOD mice receiving transient BAFF blockade were characterized by an enrichment of regulatory B lymphocytes that inhibit T1D development through IL-10 production, but this population is sensitive to deletion by anti-CD20 treatment. B lymphocytes from transient BAFFR-Fc-treated mice suppressed T cell proliferation to a greater extent than did those from controls. Proportions of B lymphocytes expressing CD73, an ecto-enzyme operating in a pathway converting proinflammatory ATP to anti-inflammatory adenosine, were also temporarily increased by transient BAFFR-Fc treatment, but not anti-CD20 therapy. These collective studies indicate transient BAFFR-Fc-mediated B lymphocyte depletion elicits long-term T1D protection by enriching regulatory B lymphocytes that are deleted by anti-CD20 cotherapy.


Assuntos
Fator Ativador de Células B/antagonistas & inibidores , Linfócitos B Reguladores/imunologia , Diabetes Mellitus Tipo 1/imunologia , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Imunoterapia/métodos , Rituximab/uso terapêutico , Linfócitos T/imunologia , Animais , Receptor do Fator Ativador de Células B/genética , Receptor do Fator Ativador de Células B/uso terapêutico , Proliferação de Células , Células Cultivadas , Terapia Combinada , Humanos , Fragmentos Fc das Imunoglobulinas/genética , Imunossupressão , Interleucina-10/metabolismo , Depleção Linfocítica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD
6.
Comp Med ; 67(4): 335-343, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28830580

RESUMO

Segmented filamentous bacterium (SFB) a gram-positive, anaerobic, and intestinal commensal organism directly influences the development of Th17 helper cells in the small intestine of mice. In NOD mice, SFB colonization interferes with the development of type 1 diabetes (T1D), a T-cell-mediated autoimmune disease, suggesting that SFB may influence Th17 cells to inhibit Th1 populations associated with the anti-ß-cell immune response. This effect is a serious concern for investigators who use NOD mice for diabetes research because the expected incidence of disease decreases markedly when they are colonized by SFB. A room housing mice for T1D studies at The Jackson Laboratory was determined by fecal PCR testing to have widespread SFB colonization of multiple NOD strains after a steady decline in the incidence of T1D was noted. Rederivation of all NOD-related mouse strains was not feasible; therefore an alternative treatment using antibiotics to eliminate SFB from colonized mice was undertaken. After antibiotic treatment, soiled bedding from NOD mouse strains housed in SFB-free high-health-status production barrier rooms was used to reintroduce the gastrointestinal microbiota. Over the past 16 mo since treating the mice and disinfecting the mouse room, regular PCR testing has shown that no additional SFB colonization of mice has occurred, and the expected incidence of T1D has been reestablished in the offspring of treated mice.


Assuntos
Ampicilina/farmacologia , Antibacterianos/farmacologia , Diabetes Mellitus Tipo 1/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/veterinária , Intestinos/efeitos dos fármacos , Criação de Animais Domésticos/métodos , Animais , Descontaminação/métodos , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Modelos Animais de Doenças , Monitoramento Ambiental/métodos , Fezes/microbiologia , Predisposição Genética para Doença , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/microbiologia , Interações Hospedeiro-Patógeno , Intestinos/imunologia , Intestinos/microbiologia , Camundongos Endogâmicos NOD , Fenótipo , Células Th1/imunologia , Células Th1/microbiologia , Células Th17/imunologia , Células Th17/microbiologia , Fatores de Tempo
7.
J Immunol ; 198(11): 4255-4267, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28461573

RESUMO

B lymphocytes play a key role in type 1 diabetes (T1D) development by serving as a subset of APCs preferentially supporting the expansion of autoreactive pathogenic T cells. As a result of their pathogenic importance, B lymphocyte-targeted therapies have received considerable interest as potential T1D interventions. Unfortunately, the B lymphocyte-directed T1D interventions tested to date failed to halt ß cell demise. IgG autoantibodies marking humans at future risk for T1D indicate that B lymphocytes producing them have undergone the affinity-maturation processes of class switch recombination and, possibly, somatic hypermutation. This study found that CRISPR/Cas9-mediated ablation of the activation-induced cytidine deaminase gene required for class switch recombination/somatic hypermutation induction inhibits T1D development in the NOD mouse model. The activation-induced cytidine deaminase protein induces genome-wide DNA breaks that, if not repaired through RAD51-mediated homologous recombination, result in B lymphocyte death. Treatment with the RAD51 inhibitor 4,4'-diisothiocyanatostilbene-2, 2'-disulfonic acid also strongly inhibited T1D development in NOD mice. The genetic and small molecule-targeting approaches expanded CD73+ B lymphocytes that exert regulatory activity suppressing diabetogenic T cell responses. Hence, an initial CRISPR/Cas9-mediated genetic modification approach has identified the AID/RAD51 axis as a target for a potentially clinically translatable pharmacological approach that can block T1D development by converting B lymphocytes to a disease-inhibitory CD73+ regulatory state.


Assuntos
Linfócitos B Reguladores/imunologia , Proteínas de Transporte/antagonistas & inibidores , Citidina Desaminase/antagonistas & inibidores , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/prevenção & controle , Ativação Linfocitária , Proteínas Nucleares/antagonistas & inibidores , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , 5'-Nucleotidase/imunologia , Animais , Autoanticorpos/imunologia , Sistemas CRISPR-Cas , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Diabetes Mellitus Experimental , Switching de Imunoglobulina , Camundongos , Camundongos Endogâmicos NOD , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Hipermutação Somática de Imunoglobulina
8.
Diabetes ; 66(3): 710-721, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27920091

RESUMO

Type 1 diabetes development in the NOD mouse model is widely reported to be dependent on high-level production by autoreactive CD4+ and CD8+ T cells of interferon-γ (IFN-γ), generally considered a proinflammatory cytokine. However, IFN-γ can also participate in tolerance-induction pathways, indicating it is not solely proinflammatory. This study addresses how IFN-γ can suppress activation of diabetogenic CD8+ T cells. CD8+ T cells transgenically expressing the diabetogenic AI4 T-cell receptor adoptively transferred disease to otherwise unmanipulated NOD.IFN-γnull , but not standard NOD, mice. AI4 T cells only underwent vigorous intrasplenic proliferation in NOD.IFN-γnull recipients. Disease-protective IFN-γ could be derived from any lymphocyte source and suppressed diabetogenic CD8+ T-cell responses both directly and through an intermediary nonlymphoid cell population. Suppression was not dependent on regulatory T cells, but was associated with increased inhibitory STAT1 to STAT4 expression levels in pathogenic AI4 T cells. Importantly, IFN-γ exposure during activation reduced the cytotoxicity of human-origin type 1 diabetes-relevant autoreactive CD8+ T cells. Collectively, these results indicate that rather than marking the most proinflammatory lymphocytes in diabetes development, IFN-γ production could represent an attempted limitation of pathogenic CD8+ T-cell activation. Thus, great care should be taken when designing possible diabetic intervention approaches modulating IFN-γ production.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Interferon gama/imunologia , Ativação Linfocitária/imunologia , RNA Mensageiro/metabolismo , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Células Cultivadas , Feminino , Humanos , Interferon gama/genética , Interferon gama/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT4/metabolismo , Baço/citologia , Linfócitos T Reguladores/efeitos dos fármacos
9.
Diabetes ; 65(7): 1977-1987, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26961115

RESUMO

While the autoimmune destruction of pancreatic ß-cells underlying type 1 diabetes (1D) development is ultimately mediated by T-cells in NOD mice and also likely humans, B-lymphocytes play an additional key pathogenic role. It appears expression of plasma membrane bound immunoglobulin (Ig) molecules that efficiently capture ß-cell antigens allows autoreactive B-lymphocytes bypassing normal tolerance induction processes to be the subset of antigen presenting cells most efficiently activating diabetogenic T-cells. NOD mice transgenically expressing Ig molecules recognizing antigens that are (insulin) or not (hen egg lysozyme; HEL) expressed by ß-cells have proven useful in dissecting the developmental basis of diabetogenic B-lymphocytes. However, these transgenic Ig specificities were originally selected for their ability to recognize insulin or HEL as foreign, rather than autoantigens. Thus, we generated and characterized NOD mice transgenically expressing an Ig molecule representative of a large proportion of naturally occurring islet-infiltrating B-lymphocytes in NOD mice recognizing the neuronal antigen peripherin. Transgenic peripherin autoreactive B-lymphocytes infiltrate NOD pancreatic islets, acquire an activated proliferative phenotype, and potently support accelerated T1D development. These results support the concept of neuronal autoimmunity as a pathogenic feature of T1D, and targeting such responses could ultimately provide an effective disease intervention approach.

10.
J Immunol ; 194(1): 407-17, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25429069

RESUMO

Type 1 diabetic NOD mice have defects in both thymic negative selection and peripheral regulation of autoreactive T cells, and induction of mixed chimerism can effectively reverse these defects. Our recent studies suggest that MHC-mismatched mixed chimerism mediates negative selection of autoreactive thymocytes in wild-type NOD and TCR-transgenic NOD.Rag1(+/+).BDC2.5 mice. However, it remains unknown how mismatched I-A(b) MHC class II can mediate deletion of autoreactive T cells positively selected by I-A(g7). In the present study, we directly tested the hypothesis that mismatched MHC class II in mixed chimeras mediates deletion of cross-reactive autoreactive thymocytes. We first identify that transgenic BDC2.5 T cells from NOD.Rag1(+/+).BDC2.5 but not NOD.Rag1(-/-).BDC2.5 mice possess cross-reactive TCRs with endogenous TCRα-chains; MHC-mismatched H-2(b) but not matched H-2(g7) mixed chimerism mediates thymic deletion of the cross-reactive transgenic T cells in NOD.Rag1(+/+).BDC2.5 mice. Second, by transplanting T cell-depleted (TCD) bone marrow (BM) cells from NOD.Rag1(+/+).BDC2.5 or NOD.Rag1(-/-).BDC2.5 mice into lethally irradiated MHC-mismatched H-2(b) C57BL/6 or MHC-matched congenic B6.H-2(g7) recipients, we demonstrate that NOD.Rag1(+/+).BDC2.5 BM-derived cross-reactive transgenic T cells, but not NOD.Rag1(-/-).BDC2.5 BM-derived non-cross-reactive transgenic T cells, can be positively selected in MHC-mismatched H-2(b) thymus. Third, by cotransplanting NOD.Rag1(+/+).BDC2.5 TCD BM cells with BM cells from MHC-mismatched T cell-deficient C57BL/6 mice into lethally irradiated MHC-matched B6.H-2(g7) recipients, we demonstrate that thymic deletion of the cross-reactive transgenic T cells is dependent on MHC-mismatched donor BM-derived APCs but not on donor BM-derived T cells. Taken together, our studies indicate that MHC-mismatched mixed chimerism can mediate thymic deletion of cross-reactive autoreactive T cells that express more than one TCR.


Assuntos
Quimerismo , Diabetes Mellitus Tipo 1/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Células Secretoras de Insulina/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Timócitos/imunologia , Animais , Autoimunidade , Células da Medula Óssea/imunologia , Transplante de Medula Óssea , Reações Cruzadas/imunologia , Diabetes Mellitus Tipo 1/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/imunologia , Células Secretoras de Insulina/patologia , Depleção Linfocítica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Timo/imunologia
11.
J Immunol ; 194(2): 560-74, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25488990

RESUMO

Interactions of B7H1 (programmed death ligand 1 [PD-L1]) with its two ligands, PD-1 and CD80, on T cells play a pivotal role in controlling T cell activation, proliferation, anergy, and apoptosis. However, the interactions between the two pathways remain unknown. Using an alloimmune response model of graft-versus-host disease (GVHD), we report in this study that: 1) Comparison of proliferation and apoptosis of wild-type (WT) and PD-1(-/-)CD4(+) conventional T (Tcon) cells in WT and B7H1(-/-) recipients revealed that B7H1/CD80 interaction per se augments T cell proliferation, and this interaction augments T cell apoptosis mediated by B7H1/PD-1 interaction. This observation was recapitulated in an in vitro MLR assay. 2) Specific blockade of the B7H1/CD80 axis by anti-B7H1 mAb reduces WT-alloreactive Tcon cell proliferation, IL-2 production, expression of PD-1, and apoptosis, resulting in worsening GVHD. In contrast, specific blockade of B7H1/CD80 interaction reduces donor PD-1(-/-) Tcon cell proliferation without an impact on apoptosis, resulting in ameliorating GVHD. 3) B7H1 fused to an Ig Fc domain (B7H1-Ig), when produced in vivo by hydrodynamic injection of B7H1-Ig plasmid, ameliorates GVHD by augmenting proliferation and apoptosis of WT- alloreactive Tcon cells. Conversely, B7H1-Ig treatment has no impact on apoptosis but augments PD-1(-/-) T cell proliferation and worsens GVHD. These results indicate that B7H1/CD80 interaction augments Tcon cell proliferation, IL-2 production, and expression of PD-1, which leads to increased apoptosis mediated by the B7H1/PD-1 pathway. Additionally, by engaging both PD-1 and CD80, B7H1-Ig can be a powerful therapeutic reagent for downregulating the T cell immune response.


Assuntos
Apoptose/imunologia , Antígeno B7-1/imunologia , Antígeno B7-H1/imunologia , Linfócitos T CD4-Positivos/imunologia , Doença Enxerto-Hospedeiro/imunologia , Receptor de Morte Celular Programada 1/imunologia , Animais , Apoptose/genética , Antígeno B7-1/genética , Antígeno B7-H1/genética , Antígeno B7-H1/farmacologia , Linfócitos T CD4-Positivos/patologia , Proliferação de Células/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , Doença Enxerto-Hospedeiro/genética , Doença Enxerto-Hospedeiro/patologia , Doença Enxerto-Hospedeiro/terapia , Interleucina-2/genética , Interleucina-2/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Receptor de Morte Celular Programada 1/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/farmacologia
12.
J Immunol ; 193(4): 2005-15, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25000982

RESUMO

In nonautoimmune recipients, induction of mixed and complete chimerism with hematopoietic progenitor cells from MHC (HLA)-matched or -mismatched donors are effective approaches for induction of organ transplantation immune tolerance in both animal models and patients. But it is still unclear whether this is the case in autoimmune recipients. With the autoimmune diabetic NOD mouse model, we report that, although mixed and complete MHC-mismatched chimerism provide immune tolerance to donor-type islet and skin transplants, neither mixed nor complete MHC-matched chimerism does. The MHC-mismatched chimerism not only tolerizes the de novo developed, but also the residual pre-existing host-type T cells in a mismatched MHC class II-dependent manner. In the MHC-mismatched chimeras, the residual host-type peripheral T cells appear to be anergic with upregulation of PD-1 and downregulation of IL-7Rα. Conversely, in the MHC-matched chimeras, the residual host-type peripheral T cells manifest both alloreactivity and autoreactivity; they not only mediate insulitis and sialitis in the recipient, but also reject allogeneic donor-type islet and skin grafts. Interestingly, transgenic autoreactive BDC2.5 T cells from Rag1(+/+), but not from Rag1(-/-), NOD mice show alloreactivity and mediate both insulitis and rejection of allografts. Taken together, MHC-mismatched, but not MHC-matched, chimerism can effectively provide transplantation immune tolerance in autoimmune recipients.


Assuntos
Autoimunidade/imunologia , Diabetes Mellitus/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Quimeras de Transplante/imunologia , Tolerância ao Transplante/imunologia , Aloenxertos/imunologia , Animais , Complexo CD3/imunologia , Linfócitos T CD4-Positivos/imunologia , Antígenos CD8/imunologia , Feminino , Rejeição de Enxerto/genética , Rejeição de Enxerto/imunologia , Células-Tronco Hematopoéticas/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Proteínas de Homeodomínio/genética , Memória Imunológica , Insulina/imunologia , Ilhotas Pancreáticas/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Endogâmicos NOD , Transplante de Órgãos , Receptor de Morte Celular Programada 1/biossíntese , Receptores de Interleucina-7/biossíntese , Transplante de Pele , Tolerância ao Transplante/genética
13.
Biol Blood Marrow Transplant ; 20(8): 1089-103, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24796279

RESUMO

Chronic graft-versus-host disease (cGVHD) is an autoimmune-like syndrome, and donor B cells play important roles in augmenting its pathogenesis. B cell-depleting anti-CD20 mAb has been administered before or after cGVHD onset for preventing or treating cGVHD in the clinic. Although administration before onset appeared to be more effective, the effect is variable and sometimes minimal. Here, we used 2 mouse cGVHD models to evaluate the preventive and therapeutic effect of anti-CD20 mAb. With the model of DBA/2 donor to MHC-matched BALB/c recipient, 1 intravenous injection of anti-CD20 mAb (40 mg/kg) the following day or on day 7 after hematopoietic cell transplantation when serum autoantibodies were undetectable effectively prevented induction of cGVHD and preserved a strong graft-versus-leukemia (GVL) effect. The separation of GVL effect from GVHD was associated with a significant reduction of donor CD4(+) T cell proliferation and expansion and protection of host thymic medullary epithelial cells. Anti-CD20 mAb administration also prevented expansion of donor T cells and induction of cGVHD in another mouse model of C57BL/6 donor to MHC-mismatched BALB/c recipients. In contrast, administration of anti-CD20 mAb after GVHD onset was not able to effectively deplete donor B cells or ameliorate cGVHD in either model. These results indicate that administration of anti-CD20 mAb before signs of cGVHD can prevent induction of autoimmune-like cGVHD while preserving a GVL effect; there is little effect if administered after cGVHD onset. This provides new insights into clinical prevention and therapy of cGVHD with B cell-depleting reagents.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Doença Enxerto-Hospedeiro/prevenção & controle , Efeito Enxerto vs Leucemia/fisiologia , Animais , Anticorpos Monoclonais Humanizados/administração & dosagem , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
14.
Biol Blood Marrow Transplant ; 20(7): 920-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24691220

RESUMO

We reported previously that anti-CD3 mAb treatment before hematopoietic cell transplantation (HCT) prevented graft-versus-host disease (GVHD) and preserved graft-versus-leukemia (GVL) effects in mice. These effects were associated with downregulated donor T cell expression of tissue-specific homing and chemokine receptors, marked reduction of donor T cell migration into GVHD target tissues, and deletion of CD103(+) dendritic cells (DCs) in mesenteric lymph nodes (MLN). MLN CD103(+) DCs and peripheral lymph node (PLN) DCs include CCR7(+) and CCR7(-) subsets, but the role of these DC subsets in regulating donor T cell expression of homing and chemokine receptors remain unclear. Here, we show that recipient CCR7(+), but not CCR7(-), DCs in MLN induced donor T cell expression of gut-specific homing and chemokine receptors in a retinoid acid-dependent manner. CCR7 regulated activated DC migration from tissue to draining lymph node, but it was not required for the ability of DCs to induce donor T cell expression of tissue-specific homing and chemokine receptors. Finally, anti-CD3 treatment depleted CCR7(+) but not CCR7(-) DCs by inducing sequential expansion and apoptosis of CCR7(+) DCs in MLN and PLN. Apoptosis of CCR7(+) DCs was associated with DC upregulation of Fas expression and natural killer cell but not T, B, or dendritic cell upregulation of FasL expression in the lymph nodes. These results suggest that depletion of CCR7(+) host-type DCs, with subsequent inhibition of donor T cell migration into GVHD target tissues, can be an effective approach in prevention of acute GVHD and preservation of GVL effects.


Assuntos
Células Dendríticas/imunologia , Receptores CCR7/imunologia , Linfócitos T/imunologia , Linfócitos T/transplante , Condicionamento Pré-Transplante/métodos , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Complexo CD3/imunologia , Movimento Celular/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Quimiocinas/imunologia , Doadores de Tecidos , Transplante Homólogo , Tropismo/imunologia
15.
Diabetes ; 63(6): 2051-62, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24458357

RESUMO

Destruction of pancreatic islet ß-cells in type 1 diabetes (T1D) is mainly mediated by autoimmune T and B lymphocytes. We reported that induction of major histocompatibility complex (MHC)-mismatched mixed chimerism reversed autoimmunity and reestablished thymic negative selection of autoreactive T cells in NOD mice, but it is still unclear how mixed chimerism tolerizes autoreactive B cells. The current studies were designed to reveal the mechanisms on how mixed chimerism tolerizes autoreactive B cells in T1D. Accordingly, mixed chimerism was induced in NOD mice through radiation-free nonmyeloablative anti-CD3/CD8 conditioning and infusion of donor CD4(+) T cell-depleted spleen and whole bone marrow (BM) cells or through myeloablative total body irradiation conditioning and reconstitution with T cell-depleted BM cells from donor and host. Kinetic analysis of percentage and yield of preplasma and plasma B cells, newly developed B-cell subsets, and their apoptosis was performed 30-60 days after transplantation. Induction of MHC-mismatched mixed chimerism results in depleting host-type pre-existing preplasma and plasma B cells as well as augmenting apoptosis of immature transitional T1 B cells, including insulin-specific B cells in a donor B cell-dependent manner. Therefore, induction of MHC-mismatched mixed chimerism depletes pre-existing and de novo-developed autoreactive B cells.


Assuntos
Anticorpos Monoclonais/imunologia , Quimerismo , Complexo Principal de Histocompatibilidade/imunologia , Baço/imunologia , Quimeras de Transplante/imunologia , Animais , Transplante de Medula Óssea , Feminino , Citometria de Fluxo , Hematopoese/imunologia , Depleção Linfocítica/métodos , Camundongos , Camundongos Endogâmicos NOD , Tolerância ao Transplante/imunologia
16.
J Immunol ; 191(1): 488-99, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23709681

RESUMO

Prevention of chronic graft-versus-host disease (cGVHD) remains a major challenge in allogeneic hematopoietic cell transplantation (HCT) owing to limited understanding of cGVHD pathogenesis and lack of appropriate animal models. In this study, we report that, in classical acute GVHD models with C57BL/6 donors and MHC-mismatched BALB/c recipients and with C3H.SW donors and MHC-matched C57BL/6 recipients, GVHD recipients surviving for >60 d after HCT developed cGVHD characterized by cutaneous fibrosis, tissue damage in the salivary gland, and the presence of serum autoantibodies. Donor CD8(+) T cells were more potent than CD4(+) T cells for inducing cGVHD. The recipient thymus and de novo-generated, donor-derived CD4(+) T cells were required for induction of cGVHD by donor CD8(+) T cells but not by donor CD4(+) T cells. Donor CD8(+) T cells preferentially damaged recipient medullary thymic epithelial cells and impaired negative selection, resulting in production of autoreactive CD4(+) T cells that perpetuated damage to the thymus and augmented the development of cGVHD. Short-term anti-CD4 mAb treatment early after HCT enabled recovery from thymic damage and prevented cGVHD. These results demonstrate that donor CD8(+) T cells cause cGVHD solely through thymic-dependent mechanisms, whereas CD4(+) T cells can cause cGVHD through either thymic-dependent or independent mechanisms.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/transplante , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/transplante , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Timo/imunologia , Timo/patologia , Doença Aguda , Animais , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Doença Crônica , Transplante de Células-Tronco Hematopoéticas , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Knockout , Timo/transplante
17.
J Immunol ; 189(1): 222-33, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22649197

RESUMO

We reported that both donor CD4(+) T and B cells in transplants were required for induction of an autoimmune-like chronic graft-versus-host disease (cGVHD) in a murine model of DBA/2 donor to BALB/c recipient, but mechanisms whereby donor B cells augment cGVHD pathogenesis remain unknown. In this study, we report that, although donor B cells have little impact on acute GVHD severity, they play an important role in augmenting the persistence of tissue damage in the acute and chronic GVHD overlapping target organs (i.e., skin and lung); they also markedly augment damage in a prototypical cGVHD target organ, the salivary gland. During cGVHD pathogenesis, donor B cells are activated by donor CD4(+) T cells to upregulate MHC II and costimulatory molecules. Acting as efficient APCs, donor B cells augment donor CD4(+) T clonal expansion, autoreactivity, IL-7Rα expression, and survival. These qualitative changes markedly augment donor CD4(+) T cells' capacity in mediating autoimmune-like cGVHD, so that they mediate disease in the absence of donor B cells in secondary recipients. Therefore, a major mechanism whereby donor B cells augment cGVHD is through augmenting the clonal expansion, differentiation, and survival of pathogenic CD4(+) T cells.


Assuntos
Autoanticorpos/biossíntese , Subpopulações de Linfócitos B/transplante , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Proliferação de Células , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Regulação para Cima/imunologia , Animais , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/patologia , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Doença Crônica , Células Clonais , Modelos Animais de Doenças , Doença Enxerto-Hospedeiro/genética , Pulmão/imunologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Camundongos Knockout , Camundongos Transgênicos , Glândulas Salivares/imunologia , Glândulas Salivares/patologia , Pele/imunologia , Pele/patologia , Regulação para Cima/genética
18.
Sci Transl Med ; 4(133): 133ra59, 2012 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-22572882

RESUMO

Type 1 diabetes (T1D) results from an autoimmune destruction of insulin-producing ß cells. Currently, islet transplantation is the only curative therapy for late-stage T1D, but the beneficial effect is limited in its duration, even under chronic immunosuppression, because of the chronic graft rejection mediated by both auto- and alloimmunity. Clinical islet transplantation is also restricted by a severe shortage of donor islets. Induction of mixed chimerism reverses autoimmunity, eliminates insulitis, and reverses new-onset but not late-stage disease in the nonobese diabetic (NOD) mouse model of T1D. Administration of gastrin and epidermal growth factor (EGF) also reverses new-onset but not late-stage T1D in this animal model. Here, we showed that combination therapy of induced mixed chimerism under a radiation-free nontoxic anti-CD3/CD8 conditioning regimen and administration of gastrin/EGF augments both ß cell neogenesis and replication, resulting in reversal of late-stage T1D in NOD mice. If successfully translated into humans, this combination therapy could replace islet transplantation as a long-term curative therapy for T1D.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Transplante das Ilhotas Pancreáticas , Animais , Terapia Combinada , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/fisiopatologia , Modelos Animais de Doenças , Fator de Crescimento Epidérmico/administração & dosagem , Feminino , Gastrinas/administração & dosagem , Humanos , Resistência à Insulina , Células Secretoras de Insulina/patologia , Células Secretoras de Insulina/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Camundongos Transgênicos , Regeneração , Pesquisa Médica Translacional , Quimeras de Transplante , Condicionamento Pré-Transplante
19.
Diabetes ; 60(2): 555-64, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21270266

RESUMO

OBJECTIVE: Induction of mixed or complete chimerism via hematopoietic cell transplantation (HCT) from nonautoimmune donors could prevent or reverse type 1 diabetes (T1D). In clinical settings, HLA-matched HCT is preferred to facilitate engraftment and reduce the risk for graft versus host disease (GVHD). Yet autoimmune T1D susceptibility is associated with certain HLA types. Therefore, we tested whether induction of mixed chimerism with major histocompatibility complex (MHC)-matched donors could reverse autoimmunity in the NOD mouse model of T1D. RESEARCH DESIGN AND METHODS: Prediabetic wild-type or transgenic BDC2.5 NOD mice were conditioned with a radiation-free GVHD preventative anti-CD3/CD8 conditioning regimen and transplanted with bone marrow (BM) from MHC-matched or mismatched donors to induce mixed or complete chimerism. T1D development and thymic deletion of host-type autoreactive T-cells in the chimeric recipients were evaluated. RESULTS: Induction of mixed chimerism with MHC-matched nonautoimmune donor BM transplants did not prevent T1D in wild-type NOD mice, although induction of complete chimerism did prevent the disease. However, induction of either mixed or complete chimerism with MHC-mismatched BM transplants prevented T1D in such mice. Furthermore, induction of mixed chimerism in transgenic BDC2.5-NOD mice with MHC-matched or -mismatched MHC II(-/-) BM transplants failed to induce thymic deletion of de novo developed host-type autoreactive T-cells, whereas induction of mixed chimerism with mismatched BM transplants did. CONCLUSIONS: Induction of mixed chimerism with MHC-mismatched, but not matched, donor BM transplants re-establishes thymic deletion of host-type autoreactive T-cells and prevents T1D, with donor antigen-presenting cell expression of mismatched MHC II molecules being required.


Assuntos
Transplante de Medula Óssea/imunologia , Quimerismo , Complexo Principal de Histocompatibilidade/imunologia , Linfócitos T/imunologia , Timo/imunologia , Animais , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos NOD , Pâncreas/imunologia
20.
Diabetes ; 59(9): 2228-36, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20530743

RESUMO

OBJECTIVE: To test whether induction of chimerism lowers the amount of donor islets required for reversal of diabetes and renders the pancreas a suitable site for islet grafts in autoimmune diabetic mice. RESEARCH DESIGN AND METHODS: The required donor islet dose for reversal of diabetes in late-stage diabetic NOD mice after transplantation into the liver or pancreas was compared under immunosuppression or after induction of chimerism. Recipient mice were monitored for blood glucose levels and measured for insulin-secretion capacity. Islet grafts were evaluated for beta-cell proliferation, beta-cell functional gene expression, and revascularization. RESULTS: With immunosuppression, transplantation of 1,000, but not 600, donor islets was able to reverse diabetes when transplanted into the liver, but transplantation of 1,000 islets was not able to reverse diabetes when transplanted into the pancreas. In contrast, after induction of chimerism, transplantation of as few as 100 donor islets was able to reverse diabetes when transplanted into either the liver or pancreas. Interestingly, when lower doses (50 or 25) of islets were transplanted, donor islets in the pancreas were much more effective in reversal of diabetes than in the liver, which was associated with higher beta-cell replication rate, better beta-cell functional gene expression, and higher vascular density of graft islets in the pancreas. CONCLUSIONS: Induction of chimerism not only provides immune tolerance to donor islets, but also markedly reduces the required amount of donor islets for reversal of diabetes. In addition, this process renders the pancreas a more superior site than the liver for donor islets in autoimmune mice.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas/fisiologia , Quimeras de Transplante , Amilases/metabolismo , Animais , Glicemia/metabolismo , Transplante de Medula Óssea/imunologia , Divisão Celular , Feminino , Regulação da Expressão Gênica , Sobrevivência de Enxerto , Imunossupressores/uso terapêutico , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/transplante , Transplante das Ilhotas Pancreáticas/métodos , Fígado/cirurgia , Luciferases/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Especificidade de Órgãos , Pâncreas/cirurgia
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