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1.
Blood ; 137(11): 1468-1477, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33202420

RESUMO

Primary central nervous system lymphoma (PCNSL) is confined to the brain, eyes, and cerebrospinal fluid without evidence of systemic spread. Rarely, PCNSL occurs in the context of immunosuppression (eg, posttransplant lymphoproliferative disorders or HIV [AIDS-related PCNSL]). These cases are poorly characterized, have dismal outcome, and are typically Epstein-Barr virus (EBV)-associated (ie, tissue-positive). We used targeted sequencing and digital multiplex gene expression to compare the genetic landscape and tumor microenvironment (TME) of 91 PCNSL tissues all with diffuse large B-cell lymphoma histology. Forty-seven were EBV tissue-negative: 45 EBV- HIV- PCNSL and 2 EBV- HIV+ PCNSL; and 44 were EBV tissue-positive: 23 EBV+ HIV+ PCNSL and 21 EBV+ HIV- PCNSL. As with prior studies, EBV- HIV- PCNSL had frequent MYD88, CD79B, and PIM1 mutations, and enrichment for the activated B-cell (ABC) cell-of-origin subtype. In contrast, these mutations were absent in all EBV tissue-positive cases and ABC frequency was low. Furthermore, copy number loss in HLA class I/II and antigen-presenting/processing genes were rarely observed, indicating retained antigen presentation. To counter this, EBV+ HIV- PCNSL had a tolerogenic TME with elevated macrophage and immune-checkpoint gene expression, whereas AIDS-related PCNSL had low CD4 gene counts. EBV-associated PCNSL in the immunosuppressed is immunobiologically distinct from EBV- HIV- PCNSL, and, despite expressing an immunogenic virus, retains the ability to present EBV antigens. Results provide a framework for targeted treatment.


Assuntos
Neoplasias do Sistema Nervoso Central/etiologia , Neoplasias do Sistema Nervoso Central/imunologia , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4/imunologia , Linfoma/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Sistema Nervoso Central/genética , Neoplasias do Sistema Nervoso Central/virologia , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Feminino , Herpesvirus Humano 4/isolamento & purificação , Humanos , Tolerância Imunológica , Linfoma/etiologia , Masculino , Pessoa de Meia-Idade , Mutação , Transcriptoma , Microambiente Tumoral
2.
Clin Exp Immunol ; 183(2): 206-20, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26422112

RESUMO

In 40% of cases of classical Hodgkin lymphoma (cHL), Epstein-Barr virus (EBV) latency-II antigens [EBV nuclear antigen 1 (EBNA1)/latent membrane protein (LMP)1/LMP2A] are present (EBV(+) cHL) in the malignant cells and antigen presentation is intact. Previous studies have shown consistently that HLA-A*02 is protective in EBV(+) cHL, yet its role in disease pathogenesis is unknown. To explore the basis for this observation, gene expression was assessed in 33 cHL nodes. Interestingly, CD8 and LMP2A expression were correlated strongly and, for a given LMP2A level, CD8 was elevated markedly in HLA-A*02(-) versus HLA-A*02(+) EBV(+) cHL patients, suggesting that LMP2A-specific CD8(+) T cell anti-tumoral immunity may be relatively ineffective in HLA-A*02(-) EBV(+) cHL. To ascertain the impact of HLA class I on EBV latency antigen-specific immunodominance, we used a stepwise functional T cell approach. In newly diagnosed EBV(+) cHL, the magnitude of ex-vivo LMP1/2A-specific CD8(+) T cell responses was elevated in HLA-A*02(+) patients. Furthermore, in a controlled in-vitro assay, LMP2A-specific CD8(+) T cells from healthy HLA-A*02 heterozygotes expanded to a greater extent with HLA-A*02-restricted compared to non-HLA-A*02-restricted cell lines. In an extensive analysis of HLA class I-restricted immunity, immunodominant EBNA3A/3B/3C-specific CD8(+) T cell responses were stimulated by numerous HLA class I molecules, whereas the subdominant LMP1/2A-specific responses were confined largely to HLA-A*02. Our results demonstrate that HLA-A*02 mediates a modest, but none the less stronger, EBV-specific CD8(+) T cell response than non-HLA-A*02 alleles, an effect confined to EBV latency-II antigens. Thus, the protective effect of HLA-A*02 against EBV(+) cHL is not a surrogate association, but reflects the impact of HLA class I on EBV latency-II antigen-specific CD8(+) T cell hierarchies.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Antígeno HLA-A2/imunologia , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/isolamento & purificação , Doença de Hodgkin/imunologia , Doença de Hodgkin/virologia , Proteínas da Matriz Viral/imunologia , Adolescente , Adulto , Idoso , Apresentação de Antígeno , Linfócitos T CD8-Positivos/virologia , Feminino , Genes MHC Classe I , Antígeno HLA-A2/genética , Herpesvirus Humano 4/genética , Doença de Hodgkin/genética , Doença de Hodgkin/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas da Matriz Viral/genética , Adulto Jovem
3.
Br J Haematol ; 143(3): 374-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18729856

RESUMO

Therapeutic vaccination combined with new drugs may cure multiple myeloma (MM). We have developed a bio-process to purify CMRF-56 monoclonal antibody (mAb) and a standard operating procedure to immunoselect blood dendritic cells (BDC). Leucopheresed mononuclear cells were cultured overnight, labelled with CMRF-56 mAb and BDC prepared using a clinical scale immunoselection system. The mean BDC yield from healthy donors was 48% (n = 6, purity 28%). Preparations from MM patients (n = 6, yield 47%, purity 35%) primed cytotoxic T lymphocytes (CTL) to clinically relevant MM antigens. This procedure can be performed readily by clinical cell manufacturing units to facilitate BDC vaccination studies.


Assuntos
Vacinas Anticâncer/uso terapêutico , Células Dendríticas/transplante , Mieloma Múltiplo/terapia , Anticorpos Monoclonais/isolamento & purificação , Apresentação de Antígeno/imunologia , Antígenos de Diferenciação/imunologia , Antígenos de Neoplasias/imunologia , Biotinilação , Células Cultivadas , Citotoxicidade Imunológica , Humanos , Separação Imunomagnética/métodos , Leucaférese , Mieloma Múltiplo/imunologia , Linfócitos T Citotóxicos/imunologia , Vacinação/métodos
4.
Cytotherapy ; 6(2): 111-21, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15203987

RESUMO

Understanding the biology of the DC and its pivotal role in immune response initiation and regulation has enabled new effective anti-cancer therapies to be developed for treatment of a wide range of tumor types. Many studies on DC-based cancer vaccine development have focused on the development of methods that can effectively deliver tumor Ags to DCs. Numerous methods have been developed or evaluated for the delivery of defined and undefined tumor Ags to DCs for processing and presentation to T lymphocytes. This review provides a brief summary of these methods, the techniques that are used in each, how they have -- or could -- be applied clinically, as well as the advantages and disadvantages of each method.


Assuntos
Apresentação de Antígeno/imunologia , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/uso terapêutico , Células Dendríticas/imunologia , Células Dendríticas/transplante , Neoplasias/terapia , Transferência Adotiva , Animais , Apresentação de Antígeno/genética , Antígenos CD/imunologia , Antígenos de Neoplasias/genética , Vacinas Anticâncer/imunologia , Técnicas de Cultura de Células/métodos , Citocinas/imunologia , DNA de Neoplasias/genética , DNA de Neoplasias/imunologia , Antígenos de Histocompatibilidade/imunologia , Humanos , Ativação Linfocitária/imunologia , Camundongos , Neoplasias/imunologia , Peptídeos/imunologia , Proteínas/imunologia , RNA Neoplásico/imunologia , Receptores de Superfície Celular/imunologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Linfócitos T/imunologia , Vacinação
6.
Clin Exp Immunol ; 108(2): 358-65, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9158111

RESUMO

The number involved in and the rate of migration of donor leucocytes into the following recipient organs (spleen, thymus, bone marrow, lung and mesenteric lymph nodes) were measured in two rat models of orthotopic liver transplantation (OLT) using donor-specific MHC class I antibodies. The first OLT model is one that does not require immunosuppression in order to achieve tolerance and involved the transplantation of DA (MHC haplotype, RT1a) livers into PVG (RT1c) recipients. The second model was one that required a 7-day (10 mg/kg) treatment with cyclosporin A (CsA) to achieve tolerance and used DA donors into Lewis (RT1(1)) recipients. Recipient organs were biopsied on days 3, 20 and 87 following OLT and donor leucocyte migration was quantified by immunohistochemistry and computer densitometry of immunoblots of detergent-solublized tissues in order to resolve both membrane-bound and soluble donor MHC class I antigen. In a separate experiment, spleen biopsies were taken following OLT on days 3 and 15 from the naturally tolerizing OLT model (DA into PVG), treated with and without CsA for 7 days and compared with the (DA into Lewis) model. The initial rate of leucocyte migration between days 3 and 21 following OLT was found to be the most rapid into the spleen, followed by the bone marrow and mesenteric lymph nodes in the naturally tolerant (DA into PVG) model when compared with the (DA into Lewis) model. The number of donor leucocytes in the spleen and mesenteric lymph nodes in both models was, however, approximately the same by 87 days. No real difference in the rate of leucocyte migration was seen in the thymus or the lung for both transplant models over the time course assayed. CsA was found to lower the rate of donor leucocyte migration only over the period it was administered. The rate of donor leucocyte migration into the spleen was still much lower 15 days after OLT in the (DA into Lewis) model compared with the (DA into PVG) model treated with and without CsA. Thus the differences in the rate of donor leucocyte migration into the spleen, bone marrow and mesenteric lymph nodes immediately following OLT may offer an explanation as to why the (DA into PVG) combination is able to accept a transplanted liver without immunosuppressive therapy.


Assuntos
Movimento Celular/imunologia , Quimiotaxia de Leucócito/imunologia , Tolerância Imunológica , Leucócitos/imunologia , Transplante de Fígado/imunologia , Animais , Medula Óssea/imunologia , Medula Óssea/patologia , Imunidade Inata , Cinética , Transplante de Fígado/patologia , Pulmão/imunologia , Pulmão/patologia , Linfonodos/imunologia , Linfonodos/patologia , Mesentério , Ratos , Ratos Endogâmicos Lew , Baço/imunologia , Baço/patologia , Timo/imunologia , Timo/patologia
7.
Transpl Immunol ; 5(1): 67-9, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9106337

RESUMO

The effect of serum from orthotopic liver retransplanted rats (re-OLT serum) on graft-versus-host disease (GVHD) was studied in rats. In the re-transplantation model of rat liver, orthotopic liver transplantation (OLT) was carried out in the DA (RT1a) into PVG (RT1c) combination; two days later the DA liver was removed and a new PVG liver implanted into the same recipient (re-OLT). In the in vivo GVHD model, male PVG rats were sublethally irradiated and injected intravenously with 3 x 10(8) DA or BN (RT1n) spleen through the penial vein. Within 1 h of the inoculation, rats of the experimental group were injected with 1 ml of re-OLT serum taken at postoperative day (POD) 7. Rats in the control group received 1 ml of normal PVG serum or syngeneic re-OLT serum (PVG-PVG, PVG-PVG). All PVG rats in the control groups died of GVHD within 21 days after the inoculation of DA or BN spleen lymphocytes. However, when the animals were treated with re-OLT serum, 100% (6/6) of the rats survived more than 60 days, following inoculation with DA lymphocytes but not with BN lymphocytes. The POD 7 re-OLT serum showed a strong inhibition against DA anti-PVG mixed lymphocyte reaction (MLR), although re-OLT serum did not contain soluble DA class I antigens, anti-DA class I or II antibody. The potential GVHD inhibitory factors in re-OLT serum may be two unique immunosuppressive proteins, which have been detected by SDS PAGE and reported previously. We conclude that re-OLT serum has immunosuppressive factors, which, at least in part, prevented the induction of GVHD in rats.


Assuntos
Doença Enxerto-Hospedeiro/prevenção & controle , Imunossupressores/sangue , Transplante de Fígado/imunologia , Animais , Doença Enxerto-Hospedeiro/sangue , Masculino , Ratos , Ratos Endogâmicos BN , Reoperação , Transplante Homólogo
10.
Transpl Int ; 9(6): 593-5, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8914241

RESUMO

The tolerance induced by orthotopic liver transplantation (OLT) in certain combinations of rat strains can be prevented by total body irradiation (TBI) of the donor. We demonstrate here that the intravenous inoculation of splenic leukocytes into irradiated donors before OLT could re-establish tolerance in association with a state of microchimerism detected in the recipients. When donor DA (RT1a) strain rats were irradiated with 1000 rad 24 h before liver harvesting and subsequent liver implantation into PVG recipients, five out of six rats died from rejection in this normally tolerogenic OLT (DA-PVG) combination. Injection of 1.5 x 10(8) splenic leukocytes from naive DA rats into the irradiated DA donor rats 24 h before OLT restored the tolerogenic potential of the liver allografts. Immunofluorescence assay revealed an increased number of donor (DA) type cells in the PVG recipient bearing a repopulated DA liver, compared to the PVG recipient of an irradiated liver. These results suggest that passenger leukocytes reconstituted by splenic leukocytes have the capacity to protect liver allografts.


Assuntos
Rejeição de Enxerto/prevenção & controle , Transfusão de Leucócitos , Transplante de Fígado , Animais , Rejeição de Enxerto/imunologia , Masculino , Ratos , Baço/imunologia , Transplante Homólogo , Irradiação Corporal Total
11.
Transpl Int ; 9(6): 607-10, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8914245

RESUMO

We investigated the effect of a prostacyclin analogue (OP 2507) on PVG (RT1c) recipients subjected to an extended anhepatic phase (AH) and transplanted orthotopically with PVG livers. All of the animals that underwent orthotopic liver transplantation (OLT) with a 20-min AH survived for 1 week with or without OP 2507, (OP) treatment (10/10, 100%). When the AH was lengthened to 45 min, the 1-week survival rate of recipients was poor in the OP-untreated groups (1/10, 10%). Treatment of the recipient with OP 2507, 0.15 micrograms/kg per minute for 30 min, prior to the 45-min AH substantially improved 1-week survival (5/6, 83.3%, P < 0.05). The serum TNF-alpha level at day 1 in OP-treated animals that underwent OLT with a 45-min AH was significantly lower than that in animals with 45-min AH OLT without OP treatment. We conclude that OP 2507 treatment has potential usefulness as a perioperative treatment when the AH is extended during OLT.


Assuntos
Epoprostenol/análogos & derivados , Rejeição de Enxerto/prevenção & controle , Transplante de Fígado , Animais , Epoprostenol/administração & dosagem , Sobrevivência de Enxerto , Masculino , Ratos , Transplante Homólogo , Fator de Necrose Tumoral alfa/análise
12.
Cell Immunol ; 106(1): 151-62, 1987 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-3568144

RESUMO

The B16 melanoma of C57BL/6 mice illustrates a deficiency in immunostimulation which may be important in some host-tumor relationships. B16 immunizes very poorly, even against its own major histocompatibility complex (MHC) antigens. We have compared the anti-MHC cytolytic response induced in vitro by B16 and by other tumors of both lymphoid and nonlymphoid origin. We have also studied the role of indomethacin and exogenous lymphokines in facilitating these responses and examined the relationship of specific and nonspecific effector cells induced. In contrast to normal lymphoid cells and two lymphoid tumor cells (EL4 and WEHI-265), the three nonlymphoid tumors, B16, Lewis lung tumor (3LL), and MC-2 fibrosarcoma, failed to induce primary cytolytic responses by themselves. MC-2 and B16 represented two different defects in immunogenicity. MC-2, which we have shown previously to induce an in vivo cytolytic response, could also immunize in vitro provided that prostaglandin production was blocked with indomethacin. In contrast B16, which is poorly immunogenic in vivo, immunized in vitro only if a concanavalin A-induced lymphokine supernatant (CS) was added as an exogenous source of "signal 2." High concentrations of the interleukin 2-containing Con A-induced spleen cell culture supernatant-induced non-H-2b-specific lymphokine-activated killer (LAK) cells in the absence of B16 stimulator cells. However, lymphokine concentrations too low to induce LAK cells enabled the otherwise nonimmunogenic B16 cells to induce specific cytolytic activity.


Assuntos
Antígenos de Neoplasias/imunologia , Linfocinas/imunologia , Neoplasias Experimentais/imunologia , Animais , Citotoxicidade Imunológica , Antígenos H-2/imunologia , Técnicas In Vitro , Indometacina/farmacologia , Linfocinas/farmacologia , Melanoma Experimental/imunologia , Camundongos , Camundongos Endogâmicos
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