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1.
Nat Immunol ; 13(7): 691-700, 2012 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-22683743

RESUMO

The human leukocyte antigens HLA-B27 and HLA-B57 are associated with protection against progression of disease that results from infection with human immunodeficiency virus type 1 (HIV-1), yet most people with alleles encoding HLA-B27 and HLA-B57 are unable to control HIV-1. Here we found that HLA-B27-restricted CD8(+) T cells in people able to control infection with HIV-1 (controllers) and those who progress to disease after infection with HIV-1 (progressors) differed in their ability to inhibit viral replication through targeting of the immunodominant epitope of group-associated antigen (Gag) of HIV-1. This was associated with distinct T cell antigen receptor (TCR) clonotypes, characterized by superior control of HIV-1 replication in vitro, greater cross-reactivity to epitope variants and enhanced loading and delivery of perforin. We also observed clonotype-specific differences in antiviral efficacy for an immunodominant HLA-B57-restricted response in controllers and progressors. Thus, the efficacy of such so-called 'protective alleles' is modulated by specific TCR clonotypes selected during natural infection, which provides a functional explanation for divergent HIV-1 outcomes.


Assuntos
Infecções por HIV/imunologia , HIV-1/imunologia , Antígenos HLA-B/imunologia , Antígeno HLA-B27/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Células Cultivadas , Epitopos de Linfócito T/imunologia , Infecções por HIV/sangue , Infecções por HIV/virologia , Sobreviventes de Longo Prazo ao HIV , Humanos , Perforina/imunologia , Replicação Viral/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia
2.
Eur J Nucl Med Mol Imaging ; 48(1): 53-66, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32592040

RESUMO

PURPOSE: Castration-resistant prostate cancer (CRPC) is the most common cause of death in men. The effectiveness of HDAC inhibitors has been demonstrated by preclinical models, but not in clinical studies, probably due to the ineffectively accumulation of HDACI in prostate cancer cells. The purpose of this work was to evaluate effects of a novel HDACI (CN133) on CRPC xenograft model and 22Rv1 cells, and develops methods, PET/CT imaging, to detect the therapeutic effects of CN133 on this cancer. METHODS: We designed and performed study to compare the effects of CN133 with SAHA on the 22Rv1 xenograft model and 22Rv1 cells. Using PET/CT imaging with [11C] Martinostat and [18F] FDG, we imaged mice bearing 22Rv1 xenografts before and after 21-day treatment with placebo and CN133 (1 mg/kg), and uptake on pre-treatment and post-treatment imaging was measured. The anti-tumor mechanisms of CN133 were investigated by qPCR, western blot, and ChIP-qPCR. RESULTS: Our data showed that the CN133 treatment led to a 50% reduction of tumor volume compared to the placebo that was more efficacious than SAHA treatment in this preclinical model. [11C] Martinostat PET imaging could identify early lesions of prostate cancer and can also be used to monitor the therapeutic effect of CN133 in CRPC. Using pharmacological approaches, we demonstrated that effects of CN133 showed almost 100-fold efficacy than SAHA treatment in the experiment of cell proliferation, invasion, and migration. The anti-tumor mechanisms of CN133 were due to the inhibition of AR signaling pathway activity by decreased HDAC 2 and 3 protein expressions. CONCLUSION: Taken together, these studies provide not only a novel epigenetic approach for prostate cancer therapy but also offering a potential tool, [11C] Martinostat PET/CT imaging, to detect the early phase of prostate cancer and monitor therapeutic effect of CN133. These results will likely lead to human trials in the future.


Assuntos
Inibidores de Histona Desacetilases , Neoplasias de Próstata Resistentes à Castração , Animais , Linhagem Celular Tumoral , Proliferação de Células , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Masculino , Camundongos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias de Próstata Resistentes à Castração/diagnóstico por imagem , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Proc Natl Acad Sci U S A ; 115(8): 1877-1882, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29437954

RESUMO

HIV controllers (HCs) are individuals who can naturally control HIV infection, partially due to potent HIV-specific CD8+ T cell responses. Here, we examined the hypothesis that superior function of CD8+ T cells from HCs is encoded by their T cell receptors (TCRs). We compared the functional properties of immunodominant HIV-specific TCRs obtained from HLA-B*2705 HCs and chronic progressors (CPs) following expression in primary T cells. T cells transduced with TCRs from HCs and CPs showed equivalent induction of epitope-specific cytotoxicity, cytokine secretion, and antigen-binding properties. Transduced T cells comparably, albeit modestly, also suppressed HIV infection in vitro and in humanized mice. We also performed extensive molecular dynamics simulations that provided a structural basis for similarities in cytotoxicity and epitope cross-reactivity. These results demonstrate that the differential abilities of HIV-specific CD8+ T cells from HCs and CPs are not genetically encoded in the TCRs alone and must depend on additional factors.


Assuntos
Linfócitos T CD8-Positivos/fisiologia , Epitopos de Linfócito T/genética , Infecções por HIV/imunologia , HIV-1/imunologia , Receptores de Antígenos de Linfócitos T/genética , Clonagem Molecular , Regulação da Expressão Gênica/imunologia , Células HEK293 , Antígeno HLA-B27 , Humanos , Células Jurkat
4.
Br J Neurosurg ; : 1-7, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33538210

RESUMO

BACKGROUND: The selection of a correct level in lumbar spinal stenosis (LSS) remains a common problem and is critically important to the effectiveness of this surgical treatment. Surgery is invasive, and extended laminectomy may lead to secondary surgical complications. The application of diffuse tensor imagining (DTI) and paraspinal mapping (PM) in addition to conventional magnetic resonance imaging (cMRI) may be helpful in this respect. However, the superiority of cMRI + DTI over cMRI+ (DTI or PM) in reducing decompression has not yet been established. METHODS: We compared the surgical levels, determined by cMRI + DTI and cMRI+ (DTI or PM) (self-control). Treatment outcome measurements were performed at two weeks, three months, six months, and twelve months postoperatively. RESULTS: The surgical levels determined by cMRI ± DTI showed less than that determined by cMRI± (DTI or PM) with statistically significant differences (p value = 0.0199) and cMRI ± PM with no statistically significant differences (p value = 0.5503). CONCLUSIONS: The effectiveness of cMRI ± DTI in the reduction of the surgical levels in degenerative lumbar spinal stenosis is superior than that of cMRI± (DTI or PM).

5.
FASEB J ; 33(5): 6596-6608, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30802149

RESUMO

Blockade of immune-checkpoint programmed cell death protein 1 (PD-1) or programmed cell death ligand 1 can enhance effector T-cell responses. However, the lack of response in many patients to checkpoint-inhibitor therapies emphasizes the need for combination immunotherapies to pursue maximal antitumor efficacy. We have previously demonstrated that antagonism of C-X-C chemokine receptor type 4 (CXCR4) by plerixafor (AMD3100) can decrease regulatory T (Treg)-cell intratumoral infiltration. Therefore, a combination of these 2 therapies might increase antitumor effects. Here, we evaluated the antitumor efficacy of AMD3100 and anti-PD-1 (αPD-1) antibody alone or in combination in an immunocompetent syngeneic mouse model of ovarian cancer. We found that AMD3100, a highly specific CXCR4 antagonist, directly down-regulated the expression of both C-X-C motif chemokine 12 (CXCL12) and CXCR4 in vitro and in vivo in tumor cells. AMD3100 and αPD-1 significantly inhibited tumor growth and prolonged the survival of tumor-bearing mice when given as monotherapy. Combination of these 2 agents significantly enhanced antitumor effects compared with single-agent administration. Benefits of tumor control and animal survival were associated with immunomodulation mediated by these 2 agents, which were characterized by increased effector T-cell infiltration, increased effector T-cell function, and increased memory T cells in tumor microenvironment. Intratumoral Treg cells were decreased, and conversion of Treg cells into T helper cells was increased by AMD3100 treatment. Intratumoral myeloid-derived suppressor cells were decreased by the combined treatment, which was associated with decreased IL-10 and IL-6 in the ascites. Also, the combination therapy decreased suppressive leukocytes and facilitated M2-to-M1 macrophage polarization in the tumor. These results suggest that AMD3100 could be used to target the CXCR4-CXCL12 axis to inhibit tumor growth and prevent multifaceted immunosuppression alone or in combination with αPD-1 in ovarian cancer, which could be clinically relevant to patients with this disease.-Zeng, Y., Li, B., Liang, Y., Reeves, P. M., Qu, X., Ran, C., Liu, Q., Callahan, M. V., Sluder, A. E., Gelfand, J. A., Chen, H., Poznansky, M. C. Dual blockade of CXCL12-CXCR4 and PD-1-PD-L1 pathways prolongs survival of ovarian tumor-bearing mice by prevention of immunosuppression in the tumor microenvironment.


Assuntos
Antígeno B7-H1 , Quimiocina CXCL12 , Compostos Heterocíclicos/farmacologia , Tolerância Imunológica/efeitos dos fármacos , Proteínas de Neoplasias , Neoplasias Ovarianas , Receptor de Morte Celular Programada 1 , Receptores CXCR4 , Transdução de Sinais , Microambiente Tumoral , Animais , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Benzilaminas , Linhagem Celular Tumoral , Quimiocina CXCL12/antagonistas & inibidores , Quimiocina CXCL12/imunologia , Ciclamos , Feminino , Camundongos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/imunologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptores CXCR4/antagonistas & inibidores , Receptores CXCR4/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
6.
Pharmacol Res ; 159: 105010, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32544428

RESUMO

AMD3100 (plerixafor), a CXCR4 antagonist, has opened a variety of avenues for potential therapeutic approaches in different refractory diseases. The CXCL12/CXCR4 axis and its signaling pathways are involved in diverse disorders including HIV-1 infection, tumor development, non-Hodgkin lymphoma, multiple myeloma, WHIM Syndrome, and so on. The mechanisms of action of AMD3100 may relate to mobilizing hematopoietic stem cells, blocking infection of X4 HIV-1, increasing circulating neutrophils, lymphocytes and monocytes, reducing myeloid-derived suppressor cells, and enhancing cytotoxic T-cell infiltration in tumors. Here, we first revisit the pharmacological discovery of AMD3100. We then review monotherapy of AMD3100 and combination use of AMD3100 with other agents in various diseases. Among those, we highlight the perspective of AMD3100 as an immunomodulator to regulate immune responses particularly in the tumor microenvironment and synergize with other therapeutics. All the pre-clinical studies support the clinical testing of the monotherapy and combination therapies with AMD3100 and further development for use in humans.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Antineoplásicos/uso terapêutico , Benzilaminas/uso terapêutico , Ciclamos/uso terapêutico , Infecções por HIV/tratamento farmacológico , Neoplasias/tratamento farmacológico , Receptores CXCR4/antagonistas & inibidores , Animais , Fármacos Anti-HIV/efeitos adversos , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Benzilaminas/efeitos adversos , Ciclamos/efeitos adversos , Contaminação de Medicamentos , Infecções por HIV/imunologia , Infecções por HIV/metabolismo , Infecções por HIV/virologia , Humanos , Neoplasias/imunologia , Neoplasias/metabolismo , Doenças da Imunodeficiência Primária/tratamento farmacológico , Doenças da Imunodeficiência Primária/imunologia , Doenças da Imunodeficiência Primária/metabolismo , Receptores CXCR4/metabolismo , Transdução de Sinais , Microambiente Tumoral , Verrugas/tratamento farmacológico , Verrugas/imunologia , Verrugas/metabolismo
7.
Pharmacol Res ; 157: 104843, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32360582

RESUMO

Both antitumor and protumor property of mesenchymal stem cells (MSCs) have been demonstrated. We hypothesize that this contradiction is due to the heterogeneity of MSC subsets and that extracellular vesicles (EVs) from distinct MSC subsets can transfer the corresponding antitumor activities. Here we evaluated the antitumor activities of two subsets of adipose-derived mesenchymal stem cells (ADSCs) and ADSC-derived EVs (ADSC-EVs) in immunocompetent syngeneic mouse models of breast cancer. We identified CD90high and CD90low ADSC subsets and demonstrated that CD90high ADSCs could be converted into CD90low ADSCs by stimulation with LPS. CD90low ADSCs and its derived EVs significantly inhibited tumor growth in tumor-bearing mice. Benefit of tumor control were associated with decreased tumor cell proliferation and migration, and enhanced tumor cell apoptosis mediated by ADSC-EVs. Antioncogenic miRNA-16-5p loaded CD90low ADSC-EVs further significantly enhanced antitumor activities. Taken together, this study represents the first attempt to apply our newly identified antitumor ADSCs and its derived EVs in preclinical treatment of breast cancer. This study also provides the evidence that EVs can serve as a novel and effective therapeutics or drug delivery vesicle. This new therapeutic approach could be potentially applicable to breast cancer and many other types of cancer.


Assuntos
Neoplasias da Mama/terapia , Vesículas Extracelulares/transplante , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Tecido Adiposo/citologia , Animais , Apoptose , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Vesículas Extracelulares/imunologia , Vesículas Extracelulares/metabolismo , Feminino , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Invasividade Neoplásica , Fenótipo , Antígenos Thy-1/metabolismo , Carga Tumoral
8.
J Immunol ; 199(4): 1319-1332, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28710250

RESUMO

Brief exposure of skin to near-infrared (NIR) laser light has been shown to augment the immune response to intradermal vaccination and thus act as an immunologic adjuvant. Although evidence indicates that the NIR laser adjuvant has the capacity to activate innate subsets including dendritic cells (DCs) in skin as conventional adjuvants do, the precise immunological mechanism by which the NIR laser adjuvant acts is largely unknown. In this study we sought to identify the cellular target of the NIR laser adjuvant by using an established mouse model of intradermal influenza vaccination and examining the alteration of responses resulting from genetic ablation of specific DC populations. We found that a continuous wave (CW) NIR laser adjuvant broadly modulates migratory DC (migDC) populations, specifically increasing and activating the Lang+ and CD11b-Lang- subsets in skin, and that the Ab responses augmented by the CW NIR laser are dependent on DC subsets expressing CCR2 and Langerin. In comparison, a pulsed wave NIR laser adjuvant showed limited effects on the migDC subsets. Our vaccination study demonstrated that the efficacy of the CW NIR laser is significantly better than that of the pulsed wave laser, indicating that the CW NIR laser offers a desirable immunostimulatory microenvironment for migDCs. These results demonstrate the unique ability of the NIR laser adjuvant to selectively target specific migDC populations in skin depending on its parameters, and highlight the importance of optimization of laser parameters for desirable immune protection induced by an NIR laser-adjuvanted vaccine.


Assuntos
Células Dendríticas/imunologia , Vacinas contra Influenza/imunologia , Raios Infravermelhos , Lasers , Pele/imunologia , Pele/efeitos da radiação , Vacinação/métodos , Adjuvantes Imunológicos , Animais , Antígenos de Superfície/metabolismo , Movimento Celular , Células Dendríticas/fisiologia , Vacinas contra Influenza/administração & dosagem , Injeções Intradérmicas , Lectinas Tipo C/metabolismo , Lectinas de Ligação a Manose/metabolismo , Camundongos , Receptores CCR2/genética , Receptores CCR2/metabolismo
9.
J Virol ; 91(6)2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28077649

RESUMO

Functional analysis of T-cell responses in HIV-infected individuals has indicated that virus-specific CD8+ T cells with superior antiviral efficacy are well represented in HIV-1 controllers but are rare or absent in HIV-1 progressors. To define the role of individual T-cell receptor (TCR) clonotypes in differential antiviral CD8+ T-cell function, we performed detailed functional and mass cytometric cluster analysis of multiple CD8+ T-cell clones recognizing the identical HLA-B*2705-restricted HIV-1 epitope KK10 (KRWIILGLNK). Effective and ineffective CD8+ T-cell clones segregated based on responses to HIV-1-infected and peptide-loaded target cells. Following cognate peptide stimulation, effective HIV-specific clones displayed significantly more rapid TCR signal propagation, more efficient initial lytic granule release, and more sustained nonlytic cytokine and chemokine secretion than ineffective clones. To evaluate the TCR clonotype contribution to CD8+ T-cell function, we cloned the TCR α and ß chain genes from one effective and two ineffective CD8+ T-cell clones from an elite controller into TCR-expressing lentivectors. We show that Jurkat/MA cells and primary CD8+ T cells transduced with lentivirus expressing TCR from one of the ineffective clones exhibited a level of activation by cognate peptide and inhibition of in vitro HIV-1 infection, respectively, that were comparable to those of the effective clonotype. Taken together, these data suggest that the potent antiviral capacity of some HIV-specific CD8+ T cells is a consequence of factors in addition to TCR sequence that modulate functionality and contribute to the increased antiviral capacity of HIV-specific CD8+ T cells in elite controllers to inhibit HIV infection.IMPORTANCE The greater ex vivo antiviral inhibitory activity of CD8+ T cells from elite controllers than from HIV-1 progressors supports the crucial role of effective HIV-specific CD8+ T cells in controlling HIV-1 replication. The contribution of TCR clonotype to inhibitory potency was investigated by delineating the responsiveness of effective and ineffective CD8+ T-cell clones recognizing the identical HLA-B*2705-restricted HIV-1 Gag-derived peptide, KK10 (KRWIILGLNK). KK10-stimulated "effective" CD8+ T-cell clones displayed significantly more rapid TCR signal propagation, more efficient initial lytic granule release, and more sustained cytokine and chemokine secretion than "ineffective" CD8+ T-cell clones. However, TCRs cloned from an effective and one of two ineffective clones conferred upon primary CD8+ T cells the equivalent potent capacity to inhibit HIV-1 infection. Taken together, these data suggest that other factors aside from intrinsic TCR-peptide-major histocompatibility complex (TCR-peptide-MHC) reactivity can contribute to the potent antiviral capacity of some HIV-specific CD8+ T-cell clones.


Assuntos
HIV-1/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/virologia , Células Cultivadas , Clonagem Molecular , Epitopos de Linfócito T/imunologia , Expressão Gênica , Humanos , Receptores de Antígenos de Linfócitos T/genética
10.
J Virol ; 91(22)2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28878089

RESUMO

Immune control of human immunodeficiency virus type 1 (HIV) infection is typically associated with effective Gag-specific CD8+ T-cell responses. We here focus on HLA-B*14, which protects against HIV disease progression, but the immunodominant HLA-B*14-restricted anti-HIV response is Env specific (ERYLKDQQL, HLA-B*14-EL9). A subdominant HLA-B*14-restricted response targets Gag (DRYFKTLRA, HLA-B*14-DA9). Using HLA-B*14/peptide-saporin-conjugated tetramers, we show that HLA-B*14-EL9 is substantially more potent at inhibiting viral replication than HLA-B*14-DA9. HLA-B*14-EL9 also has significantly higher functional avidity (P < 0.0001) and drives stronger selection pressure on the virus than HLA-B*14-DA9. However, these differences were HLA-B*14 subtype specific, applying only to HLA-B*14:02 and not to HLA-B*14:01. Furthermore, the HLA-B*14-associated protection against HIV disease progression is significantly greater for HLA-B*14:02 than for HLA-B*14:01, consistent with the superior antiviral efficacy of the HLA-B*14-EL9 response. Thus, although Gag-specific CD8+ T-cell responses may usually have greater anti-HIV efficacy, factors independent of protein specificity, including functional avidity of individual responses, are also critically important to immune control of HIV.IMPORTANCE In HIV infection, although cytotoxic T lymphocytes (CTL) play a potentially critical role in eradication of viral reservoirs, the features that constitute an effective response remain poorly defined. We focus on HLA-B*14, unique among HLAs associated with control of HIV in that the dominant CTL response is Env specific, not Gag specific. We demonstrate that Env-specific HLA-B*14-restricted activity is substantially more efficacious than the subdominant HLA-B*14-restricted Gag response. Env immunodominance over Gag and strong Env-mediated selection pressure on HIV are observed only in subjects expressing HLA-B*14:02, and not HLA-B*14:01. This reflects the increased functional avidity of the Env response over Gag, substantially more marked for HLA-B*14:02. Finally, we show that HLA-B*14:02 is significantly more strongly associated with viremic control than HLA-B*14:01. These findings indicate that, although Gag-specific CTL may usually have greater anti-HIV efficacy than Env responses, factors independent of protein specificity, including functional avidity, may carry greater weight in mediating effective control of HIV.


Assuntos
Proteína gp160 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Antígeno HLA-B14/imunologia , Imunidade Celular , Peptídeos/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia , Adulto , Linfócitos T CD8-Positivos , Infecções por HIV/patologia , Infecções por HIV/terapia , Humanos
11.
J Virol ; 89(21): 10735-47, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26269189

RESUMO

UNLABELLED: Previous studies have shown that elite controllers with minimal effector T cell responses harbor a low-frequency, readily expandable, highly functional, and broadly directed memory population. Here, we interrogated the in vivo relevance of this cell population by investigating whether the breadth of expandable memory responses is associated with the magnitude of residual viremia in individuals achieving durable suppression of HIV infection. HIV-specific memory CD8(+) T cells were expanded by using autologous epitopic and variant peptides. Viral load was measured by an ultrasensitive single-copy PCR assay. Following expansion, controllers showed a greater increase in the overall breadth of Gag responses than did untreated progressors (P = 0.01) as well as treated progressors (P = 0.0003). Nef- and Env-specific memory cells expanded poorly for all groups, and their expanded breadths were indistinguishable among groups (P = 0.9 for Nef as determined by a Kruskal-Wallis test; P = 0.6 for Env as determined by a Kruskal-Wallis test). More importantly, we show that the breadth of expandable, previously undetectable Gag-specific responses was inversely correlated with residual viral load (r = -0.6; P = 0.009). Together, these data reveal a direct link between the abundance of Gag-specific expandable memory responses and prolonged maintenance of low-level viremia. Our studies highlight a CD8(+) T cell feature that would be desirable in a vaccine-induced T cell response. IMPORTANCE: Many studies have shown that the rare ability of some individuals to control HIV infection in the absence of antiretroviral therapy appears to be heavily dependent upon special HIV-specific killer T lymphocytes that are able to inhibit viral replication. The identification of key features of these immune cells has the potential to inform rational HIV vaccine design. This study shows that a special subset of killer lymphocytes, known as central memory CD8(+) T lymphocytes, is at least partially involved in the durable control of HIV replication. HIV controllers maintain a large proportion of Gag-specific expandable memory CD8(+) T cells involved in ongoing viral suppression. These data suggest that induction of this cell subset by future HIV vaccines may be important for narrowing possible routes of rapid escape from vaccine-induced CD8(+) T cell responses.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Memória Imunológica , ELISPOT , Citometria de Fluxo , Produtos do Gene gag/metabolismo , Humanos , Massachusetts , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase em Tempo Real , Estatísticas não Paramétricas , Carga Viral
12.
J Orthop Sci ; 21(4): 431-438, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27188929

RESUMO

INTRODUCTION: In lumbar spinal stenosis, correlating symptoms and physical examination findings with decompression levels based on common imaging is not reliable. Paraspinal mapping (PM) and diffusion tensor imaging (DTI) may be possible to prevent the false positive occurrences with MRI and show clear benefits to reduce the decompression levels of lumbar spinal stenosis than conventional magnetic resonance imaging (MRI) + neurogenic examination (NE). However, they must have enough positive rate with levels which should be decompressed at first. The study aimed to confirm that the positive of DTI and PM is enough in levels which should be decompressed in lumbar spinal stenosis. MATERIALS AND METHODS: The study analyzed the positive of DTI and PM as well as compared the preoperation scores to the postoperation scores, which were assessed preoperatively and at 2 weeks, 3 months 6 months, and 12 months postoperatively. RESULTS: 96 patients underwent the single level decompression surgery. The positive rate among PM, DTI, and (PM or DTI) was 76%, 98%, 100%, respectively. All post-operative Oswestry Disability Index (ODI), visual analog scale for back pain (VAS-BP) and visual analog scale for leg pain (VAS-LP) scores at 2 weeks postoperatively were measured improvement than the preoperative ODI, VAS-BP and VAS-LP scores with statistically significance (p-value = 0.000, p-value = 0.000, p-value = 0.000, respectively). CONCLUSIONS: In degenetive lumbar spinal stenosis, the positive rate of (DTI or PM) is enough in levels which should be decompressed, thence using the PM and DTI to determine decompression levels will not miss the level which should be operated.


Assuntos
Descompressão Cirúrgica , Vértebras Lombares , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Imagem de Tensor de Difusão , Eletromiografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Valor Preditivo dos Testes , Resultado do Tratamento , Adulto Jovem
13.
Biochem Biophys Res Commun ; 450(1): 202-7, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24878527

RESUMO

Reactivation of latent HIV-1 is a promising strategy for the clearance of the viral reservoirs. Because of the limitations of current agents, identification of new latency activators is urgently required. Using an established model of HIV-1 latency, we examined the effect of Oxaliplatin on latent HIV-1 reactivation. We showed that Oxaliplatin, alone or in combination with valproic acid (VPA), was able to reactivate HIV-1 without inducing global T cell activation. We also provided evidence that Oxaliplatin reactivated HIV-1 expression by inducing nuclear factor kappa B (NF-κB) nuclear translocation. Our results indicated that Oxaliplatin could be a potential drug candidate for anti-latency therapies.


Assuntos
HIV-1/imunologia , Ativação Linfocitária/imunologia , NF-kappa B/imunologia , Compostos Organoplatínicos/farmacologia , Linfócitos T/imunologia , Linfócitos T/virologia , Ativação Viral/imunologia , Latência Viral/imunologia , Células Cultivadas , HIV-1/efeitos dos fármacos , Humanos , Ativação Linfocitária/efeitos dos fármacos , Oxaliplatina , Linfócitos T/efeitos dos fármacos , Ativação Viral/efeitos dos fármacos , Latência Viral/efeitos dos fármacos
14.
J Immunol ; 188(12): 5924-34, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22586036

RESUMO

Viruses evade immune detection partly through immune-associated mutations. Analyses of HIV sequences derived from infected individuals have identified numerous examples of HLA-associated mutations within or adjacent to T cell epitopes, but the potential impact of most mutations on epitope production and presentation remains unclear. The multistep breakdown of proteins into epitopes includes trimming of N-extended peptides into epitopes by aminopeptidases before loading onto MHC class I molecules. Definition of sequence signatures that modulate epitope production would lead to a better understanding of factors driving viral evolution and immune escape at the population level. In this study, we identified cytosolic aminopeptidases cleavage preferences in primary cells and its impact on HIV Ag degradation into epitopes in primary human cell extracts by mass spectrometry and on epitope presentation to CTL. We observed a hierarchy of preferred amino acid cleavage by cytosolic aminopeptidases. We demonstrated that flanking mutations producing more or less cleavable motifs can increase or decrease epitope production and presentation by up to 14-fold. We found that the efficiency of epitope production correlates with cleavability of flanking residues. These in vitro findings were supported by in vivo population-level analyses of clinically derived viral sequences from 1134 antiretroviral-naive HIV-infected individuals: HLA-associated mutations immune pressures drove the selection of residues that are less cleavable by aminopeptidases predominantly at N-flanking sites, leading to reduced epitope production and immune recognition. These results underscore an important and widespread role of Ag processing mutations in HIV immune escape and identify molecular mechanisms underlying impaired epitope presentation.


Assuntos
Aminopeptidases/imunologia , Apresentação de Antígeno/imunologia , Epitopos de Linfócito T/imunologia , Infecções por HIV/imunologia , Proteínas do Vírus da Imunodeficiência Humana/imunologia , Evasão da Resposta Imune/imunologia , Aminopeptidases/genética , Aminopeptidases/metabolismo , Apresentação de Antígeno/genética , Separação Celular , Epitopos de Linfócito T/metabolismo , Citometria de Fluxo , Infecções por HIV/genética , Infecções por HIV/metabolismo , Antígenos de Histocompatibilidade Classe I/imunologia , Proteínas do Vírus da Imunodeficiência Humana/metabolismo , Humanos , Evasão da Resposta Imune/genética , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Mutação
15.
J Immunother Cancer ; 12(6)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926151

RESUMO

BACKGROUND: Lung metastasis is the primary cause of breast cancer-related mortality. Neutrophil extracellular traps (NETs) are involved in the progression of breast cancer. However, the mechanism of NET formation is not fully understood. This study posits that tumor cell-released autophagosomes (TRAPs) play a crucial role in this process. METHODS: TRAPs were isolated from breast cancer cell lines to analyze their impact on NET formation in both human and mouse neutrophils. The study used both in vitro and in vivo models, including Toll-like receptor 4 (TLR4-/-) mice and engineered breast cancer cell lines. Immunofluorescence, ELISA, Western blotting, RNA sequencing, and flow cytometry were employed to dissect the signaling pathways leading to NET production and to explore their immunosuppressive effects, particularly focusing on the impact of NETs on T-cell function. The therapeutic potential of targeting TRAP-induced NETs and their immunosuppressive functions was evaluated using DNase I and αPD-L1 antibodies. Clinical relevance was assessed by correlating circulating levels of TRAPs and NETs with lung metastasis in patients with breast cancer. RESULTS: This study showed that TRAPs induced the formation of NETs in both human and mouse neutrophils by using the high mobility group box 1 and activating the TLR4-Myd88-ERK/p38 signaling axis. More importantly, PD-L1 carried by TRAP-induced NETs inhibited T-cell function in vitro and in vivo, thereby contributing to the formation of lung premetastatic niche (PMN) immunosuppression. In contrast, Becn1 KD-4T1 breast tumors with decreased circulating TRAPs in vivo reduced the formation of NETs, which in turn attenuated the immunosuppressive effects in PMN and resulted in a reduction of breast cancer pulmonary metastasis in murine models. Moreover, treatment with αPD-L1 in combination with DNase I that degraded NETs restored T-cell function and significantly reduced tumor metastasis. TRAP levels in the peripheral blood positively correlated with NET levels and lung metastasis in patients with breast cancer. CONCLUSIONS: Our results demonstrate a novel role of TRAPs in the formation of PD-L1-decorated NETs, which may provide a new strategy for early detection and treatment of pulmonary metastasis in patients with breast cancer.


Assuntos
Autofagossomos , Antígeno B7-H1 , Neoplasias da Mama , Armadilhas Extracelulares , Neoplasias Pulmonares , Animais , Humanos , Camundongos , Feminino , Neoplasias da Mama/patologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Neoplasias Pulmonares/secundário , Armadilhas Extracelulares/metabolismo , Antígeno B7-H1/metabolismo , Autofagossomos/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linhagem Celular Tumoral
16.
Clin Cancer Res ; 27(23): 6543-6558, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34426437

RESUMO

PURPOSE: There is still no standard nonsurgical regimen for conventional chondrosarcoma (CHS). We aimed to identify whether any CHSs have a favored microenvironment for immunotherapy via multidimensional evaluation of the immunologic characteristics of this tumor. EXPERIMENTAL DESIGN: We obtained 98 newly-diagnosed CHS fresh tumors from several institutions and performed comprehensive analysis of data from CyTOF, whole-exome sequencing, and flow cytometry in 22 cases. Clinical data from immunotherapy responders and nonresponders were compared to explore possible biomarkers of immunotherapy response. Mechanism studies were conducted to interpret the biomarker phenotype. RESULTS: Based on the integrated data of single-cell CyTOF and flow cytometry, the CHS immune-microenvironment phenotypes were classified into three groups: subtype I, the "granulocytic-myeloid-derived suppressor cell (G-MDSC) dominant" cluster, with high number of HLA-DR- CD14- myeloid cells; subtype II, the "immune exhausted" cluster, with high exhausted T-cell and dendritic-cell infiltration; and subtype III, the "immune desert" cluster, with few immune cells. Immune cell-rich subtypes (subtype I and II) were characterized by IDH mutation, pathologic high grade, and peritumoral edema, while subtype I cases were exclusively featured by myxoid transformation. In clinical practice involving 12 individuals who received PD-1 antibody immunotherapy, all of the 3 cases with controlled diseases were retrospectively classified as subtype II. In mechanism, IDH mutation significantly elevated chemokine levels and immune-cell infiltration in immune-inactivated tumors. CONCLUSIONS: This study is the first to provide immune characterization of CHS, representing a major step to precise immunotherapy against this malignancy. Immunotherapy is promising for the "immune exhausted" subtype of patients with CHS.


Assuntos
Condrossarcoma , Células Supressoras Mieloides , Condrossarcoma/genética , Condrossarcoma/terapia , Humanos , Imunoterapia/métodos , Estudos Retrospectivos , Microambiente Tumoral/genética
17.
J Virol ; 83(7): 3138-49, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19158248

RESUMO

Defining the antiviral efficacy of CD8 T cells is important for immunogen design, and yet most current assays do not measure the ability of responses to neutralize infectious virus. Here we show that human immunodeficiency virus (HIV)-specific cytotoxic T-lymphocyte (CTL) clones and cell lines derived from infected persons and targeting diverse epitopes differ by over 1,000-fold in their ability to retard infectious virus replication in autologous CD4 T cells during a 7-day period in vitro, despite comparable activity as assessed by gamma interferon (IFN-gamma) enzyme-linked immunospot (ELISPOT) assay. Cell lines derived from peripheral blood mononuclear cells stimulated in vitro with peptides representing targeted Gag epitopes consistently neutralized HIV better than Env-specific lines from the same person, although ineffective inhibition of virus replication is not a universal characteristic of Env-specific responses at the clonal level. Gag-specific cell lines were of higher avidity than Env-specific lines, although avidity did not correlate with the ability of Gag- or Env-specific lines to contain HIV replication. The greatest inhibition was observed with cell lines restricted by the protective HLA alleles B*27 and B*57, but stimulation with targeted Gag epitopes resulted in greater inhibition than did stimulation with targeted Env epitopes even in non-B*27/B*57 subjects. These results assessing functional virus neutralization by HIV-specific CD8 T cells indicate that there are marked epitope- and allele-specific differences in virus neutralization by in vitro-expanded CD8 T cells, a finding not revealed by standard IFN-gamma ELISPOT assay currently in use in vaccine trials, which may be of critical importance in immunogen design and testing of candidate AIDS vaccines.


Assuntos
Linfócitos T CD4-Positivos/virologia , HIV/imunologia , Linfócitos T Citotóxicos/imunologia , Alelos , Células Cultivadas , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Epitopos de Linfócito T/imunologia , Antígenos HLA/genética , Humanos , Ativação Linfocitária
18.
J Int Med Res ; 48(12): 300060520950934, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33349106

RESUMO

BACKGROUND: Femoral head collapse and coxa vara lead to internal fixator failure in elderly patients with hip fracture. External fixator application is an optimal choice; however, the existing methods have many disadvantages. METHODS: Type 31-A1.3 hip fracture models were developed in nine pairs of 1-year-old fresh bovine corpse femur specimens. Each left femur specimen was fixed by a dynamic hip screw (control group), and each right femur specimen was fixed by the slide-poking external fixator (experimental group). Vertical loading and torsion tests were then performed in both groups. RESULTS: In the vertical loading experiment, a 1000-N load was implemented. The mean vertical downward displacement of the femoral head in the experimental and control groups was 1.49322 ± 0.116280 and 2.13656 ± 0.166374 mm, respectively. In the torsion experiment, when the torsion was increased to 10.0 Nm, the mean torsion angle in the experimental and control groups was 7.9733° ± 1.65704° and 15.4889° ± 0.73228°, respectively. The slide-poking external fixator was significantly more resistant to compression and rotation than the dynamic hip screw. CONCLUSION: The slide-poking external fixator for hip fractures that was designed and developed in this study can provide sufficient stability to resist compression and rotation in hip fractures.


Assuntos
Fixadores Externos , Fraturas do Quadril , Idoso , Animais , Fenômenos Biomecânicos , Parafusos Ósseos , Bovinos , Fixação Interna de Fraturas , Fraturas do Quadril/cirurgia , Humanos , Lactente , Fixadores Internos
19.
Anal Cell Pathol (Amst) ; 2020: 8546231, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32908815

RESUMO

Platelet-rich plasma (PRP) and its byproduct platelet-poor plasma (PPP) are rich sources of cytokines in tissue damage repair. Bone marrow-derived mesenchymal stem cells (BM-MSCs) have received more and more attention for their ability to treat multiple diseases. The purpose of our study was to investigate the biologic action of PPP and PRP on BM-MSCs. The adipogenic potential of BM-MSCs revealed no obvious change, but the osteogenic ability of BM-MSCs was enhanced after treated with PRP. CCK8 assays and cell colony formation assays showed that PRP promoted cell proliferation, while this effect of PPP was not obvious. No obvious difference was found in cell cycle and apoptosis of BM-MSCs between PRP and PPP treatment. Expression of ß-galactosidase, a biological marker of senescence, was decreased upon PRP treatment which indicated that PRP provided significant protection against cellular senescence. The migratory capacity of BM-MSCs was detected by scratch and transwell assays. The results indicated that PRP could affect the migration ability of BM-MSCs. From immunofluorescence detection and western blot, we demonstrated that the level of epithelial-mesenchymal transition-related proteins was changed and several pluripotency marker genes, including Sox2, Sall4, Oct4, and Nanog, were increased. Finally, the expression of the key signal pathway such as PI3K/AKT was examined. Our findings suggested that PRP promoted cell migration of BM-MSCs via stimulating the signaling pathway of PI3K/AKT.


Assuntos
Células-Tronco Mesenquimais/metabolismo , Plasma Rico em Plaquetas/metabolismo , Animais , Apoptose , Ciclo Celular , Diferenciação Celular , Movimento Celular , Proliferação de Células , Senescência Celular , Masculino , Células-Tronco Mesenquimais/citologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais
20.
Cell Signal ; 76: 109800, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33011290

RESUMO

NK1.1- CD4+ NKG2D+ T cells are a subpopulation of regulatory T cells that downregulate the functions of CD4+ T, CD8+ T, natural killer (NK) cells, and macrophages through TGF-ß1 production. Early growth response genes 2 (Egr2) and 3 (Egr3) maintain immune homeostasis by modulating T lymphocyte development, inhibiting effector T cell function, and promoting the induction of regulatory T cells. Whether Egr2 and Egr3 directly regulate TGF-ß1 transcription in NK1.1- CD4+ NKG2D+ T cells remains elusive. The expression levels of Egr2 and Egr3 were higher in NK1.1- CD4+ NKG2D+ T cells than in NK1.1- CD4+ NKG2D- T cells. Egr2 and Egr3 expression were remarkably increased after stimulating NK1.1- CD4+ NKG2D+ T cells with sRAE or α-CD3/sRAE. The ectopic expression of Egr2 or Egr3 resulted in the enhancement of TGF-ß1 expression, while knockdown of Egr2 or Egr3 led to the decreased expression of TGF-ß1 in NK1.1- CD4+ NKG2D+ T cells. Egr2 and Egr3 directly bound with the TGF-ß1 promoter as demonstrated by the electrophoretic mobility shift assay and dual-luciferase gene reporter assay. Furthermore, the Egr2 and Egr3 expression of NK1.1- CD4+ NKG2D+ T cells could be induced by the AP-1 and NF-κB transcriptional factors, but had no involvement with the activation of NF-AT and STAT3. In conclusion, Egr2 and Egr3 induced by AP-1 and NF-κB directly initiate TGF-ß1 transcription in NK1.1- CD4+ NKG2D+ T cells. This study indicates that manipulating Egr2 and Egr3 expression would potentiate or alleviate the regulatory function of NK1.1- CD4+ NKG2D+ T cells and this strategy could be used in the therapy for patients with autoimmune diseases or tumor.


Assuntos
Linfócitos T CD4-Positivos , Proteína 2 de Resposta de Crescimento Precoce/imunologia , Proteína 3 de Resposta de Crescimento Precoce/imunologia , Fator de Crescimento Transformador beta1/imunologia , Animais , Doenças Autoimunes/imunologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Camundongos , Camundongos Transgênicos , NF-kappa B/imunologia , Neoplasias/imunologia
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