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1.
Eur J Immunol ; 54(6): e2350878, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38581345

RESUMO

Tumor-associated macrophages (TAM) are abundant in several tumor types and usually correlate with poor prognosis. Previously, we demonstrated that anti-inflammatory macrophages (M2) inhibit NK cell effector functions. Here, we explored the impact of TAM on NK cells in the context of clear-cell renal cell carcinoma (ccRCC). Bioinformatics analysis revealed that an exhausted NK cell signature strongly correlated with an M2 signature. Analysis of TAM from human ccRCC samples confirmed that they exhibited an M2-skewed phenotype and inhibited IFN-γ production by NK cells. Moreover, human M0 macrophages cultured with conditioned media from ccRCC cell lines generated macrophages with an M2-skewed phenotype (TAM-like), which alike TAM, displayed suppressive activity on NK cells. Moreover, TAM depletion in the mouse Renca ccRCC model resulted in delayed tumor growth and reduced volume, accompanied by an increased frequency of IFN-γ-producing tumor-infiltrating NK cells that displayed heightened expression of T-bet and NKG2D and reduced expression of the exhaustion-associated co-inhibitory molecules PD-1 and TIM-3. Therefore, in ccRCC, the tumor microenvironment polarizes TAM toward an immunosuppressive profile that promotes tumor-infiltrating NK cell dysfunction, contributing to tumor progression. In addition, immunotherapy strategies targeting TAM may result in NK cell reinvigoration, thereby counteracting tumor progression.


Assuntos
Carcinoma de Células Renais , Interferon gama , Neoplasias Renais , Células Matadoras Naturais , Macrófagos Associados a Tumor , Células Matadoras Naturais/imunologia , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Interferon gama/metabolismo , Interferon gama/imunologia , Humanos , Animais , Camundongos , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismo , Progressão da Doença , Linhagem Celular Tumoral , Microambiente Tumoral/imunologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Receptor Celular 2 do Vírus da Hepatite A/imunologia , Receptor de Morte Celular Programada 1/metabolismo
2.
J Immunother Cancer ; 11(3)2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36889811

RESUMO

BACKGROUND: The success of HER2-positive (HER2+) breast cancer treatment with trastuzumab, an antibody that targets HER2, relies on immune response. We demonstrated that TNFα induces mucin 4 (MUC4) expression, which shields the trastuzumab epitope on the HER2 molecule decreasing its therapeutic effect. Here, we used mouse models and samples from HER2+ breast cancer patients to unravel MUC4 participation in hindering trastuzumab effect by fostering immune evasion. METHODS: We used a dominant negative TNFα inhibitor (DN) selective for soluble TNFα (sTNFα) together with trastuzumab. Preclinical experiments were performed using two models of conditionally MUC4-silenced tumors to characterize the immune cell infiltration. A cohort of 91 patients treated with trastuzumab was used to correlate tumor MUC4 with tumor-infiltrating lymphocytes. RESULTS: In mice bearing de novo trastuzumab-resistant HER2+ breast tumors, neutralizing sTNFα with DN induced MUC4 downregulation. Using the conditionally MUC4-silenced tumor models, the antitumor effect of trastuzumab was reinstated and the addition of TNFα-blocking agents did not further decrease tumor burden. DN administration with trastuzumab modifies the immunosuppressive tumor milieu through M1-like phenotype macrophage polarization and NK cells degranulation. Depletion experiments revealed a cross-talk between macrophages and NK cells necessary for trastuzumab antitumor effect. In addition, tumor cells treated with DN are more susceptible to trastuzumab-dependent cellular phagocytosis. Finally, MUC4 expression in HER2+ breast cancer is associated with immune desert tumors. CONCLUSIONS: These findings provide rationale to pursue sTNFα blockade combined with trastuzumab or trastuzumab drug conjugates for MUC4+ and HER2+ breast cancer patients to overcome trastuzumab resistance.


Assuntos
Mucina-4 , Neoplasias , Camundongos , Animais , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico , Regulação para Baixo , Mucina-4/genética , Mucina-4/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Receptor ErbB-2 , Linhagem Celular Tumoral , Terapia de Imunossupressão , Neoplasias/tratamento farmacológico
3.
Oncoimmunology ; 11(1): 2104991, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35936986

RESUMO

NKG2D is a major natural killer (NK) cell-activating receptor that recognizes eight ligands (NKG2DLs), including MICA, and whose engagement triggers NK cell effector functions. As NKG2DLs are upregulated on tumor cells but tumors can subvert the NKG2D-NKG2DL axis, NKG2DLs constitute attractive targets for antibody (Ab)-based immuno-oncology therapies. However, such approaches require a deep characterization of NKG2DLs and NKG2D cell surface expression on primary tumor and immune cells. Here, using a bioinformatic analysis, we observed that MICA is overexpressed in renal cell carcinoma (RCC), and we also detected an association between the NKG2D-MICA axis and a diminished overall survival of RCC patients. Also, by flow cytometry (FC), we observed that MICA was the only NKG2DL over-expressed on clear cell renal cell carcinoma (ccRCC) tumor cells, including cancer stem cells (CSC) that also coexpressed NKG2D. Moreover, tumor-infiltrating leukocytes (TIL), but not peripheral blood lymphoid cells (PBL) from ccRCC patients, over-expressed MICA, ULBP3 and ULBP4. In addition, NKG2D was downregulated on peripheral blood NK cells (PBNK) from ccRCC patients but upregulated on tumor-infiltrating NK cells (TINK). These TINK exhibited impaired degranulation that negatively correlated with NKG2D expression, diminished IFN-γ production, upregulation of TIM-3, and an impaired glucose intake upon stimulation with cytokines, indicating that they are dysfunctional, display features of exhaustion and an altered metabolic fitness. We conclude that ccRCC patients exhibit a distorted MICA-NKG2D axis, and MICA emerges as the forefront NKG2DL for the development of targeted therapies in ccRCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/terapia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Neoplasias Renais/terapia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptores de Células Matadoras Naturais
4.
Nutrients ; 14(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35277082

RESUMO

Lipoteichoic acid (LTA) from Gram-positive bacteria exerts different immune effects depending on the bacterial source from which it is isolated. Lacticaseibacillus rhamnosus GG LTA (LGG-LTA) oral administration reduces UVB-induced immunosuppression and skin tumor development in mice. In the present work, we evaluate the immunomodulatory effect exerted by LGG-LTA in dendritic cells (DC) and T cells, both in vitro and in the gut-associated lymphoid tissue (GALT). During cell culture, LTA-stimulated BMDC increased CD86 and MHC-II expression and secreted low levels of pro and anti-inflammatory cytokines. Moreover, LTA-treated BMDC increased T cell priming capacity, promoting the secretion of IL-17A. On the other hand, in orally LTA-treated mice, a decrease in mature DC (lamina propria and Peyer's patches) was observed. Concomitantly, an increase in IL-12p35 and IFN-γ transcription was presented (lamina propria and Peyer's Patches). Finally, an increase in the number of CD103+ DC was observed in Peyer's patches. Together, our data demonstrate that LGG-LTA activates DC and T cells. Moreover, we show that a Th1-biased immune response is triggered in vivo after oral LTA administration. These effects justify the oral LTA activity previously observed.


Assuntos
Células Dendríticas , Linfócitos T , Animais , Lipopolissacarídeos/farmacologia , Camundongos , Ácidos Teicoicos/metabolismo , Ácidos Teicoicos/farmacologia
5.
Front Immunol ; 12: 745939, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616407

RESUMO

Natural Killer (NK) cells play a key role in cancer immunosurveillance. However, NK cells from cancer patients display an altered phenotype and impaired effector functions. In addition, evidence of a regulatory role for NK cells is emerging in diverse models of viral infection, transplantation, and autoimmunity. Here, we analyzed clear cell renal cell carcinoma (ccRCC) datasets from The Cancer Genome Atlas (TCGA) and observed that a higher expression of NK cell signature genes is associated with reduced survival. Analysis of fresh tumor samples from ccRCC patients unraveled the presence of a high frequency of tumor-infiltrating PD-L1+ NK cells, suggesting that these NK cells might exhibit immunoregulatory functions. In vitro, PD-L1 expression was induced on NK cells from healthy donors (HD) upon direct tumor cell recognition through NKG2D and was further up-regulated by monocyte-derived IL-18. Moreover, in vitro generated PD-L1hi NK cells displayed an activated phenotype and enhanced effector functions compared to PD-L1- NK cells, but simultaneously, they directly inhibited CD8+ T cell proliferation in a PD-L1-dependent manner. Our results suggest that tumors might drive the development of PD-L1-expressing NK cells that acquire immunoregulatory functions in humans. Hence, rational manipulation of these regulatory cells emerges as a possibility that may lead to improved anti-tumor immunity in cancer patients.


Assuntos
Antígeno B7-H1/biossíntese , Linfócitos T CD8-Positivos/citologia , Carcinoma de Células Renais/imunologia , Neoplasias Renais/imunologia , Células Matadoras Naturais/metabolismo , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/mortalidade , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , Conjuntos de Dados como Assunto , Intervalo Livre de Doença , Expressão Gênica , Humanos , Interferon gama/farmacologia , Interleucina-18/farmacologia , Células K562 , Estimativa de Kaplan-Meier , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Neoplasias Renais/mortalidade , Monitorização Imunológica , Monócitos/metabolismo , Proteínas Recombinantes/farmacologia , Regulação para Cima
6.
J Immunother Cancer ; 8(1)2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32518090

RESUMO

BACKGROUND: Natural killer and cytotoxic CD8+ T cells are major players during antitumor immunity. They express NKG2D, an activating receptor that promotes tumor elimination through recognition of the MHC class I chain-related proteins A and B (MICA and MICB). Both molecules are overexpressed on a great variety of tumors from different tissues, making them attractive targets for immunotherapy. However, tumors shed MICA and MICB, and the soluble forms of both (sMICA and sMICB) mediate tumor-immune escape. Some reports indicate that anti-MICA antibodies (Ab) can promote the restoration of antitumor immunity through the induction of direct antitumor effects (antibody-dependent cell-mediated cytotoxicity, ADCC) and scavenging of sMICA. Therefore, we reasoned that an active induction of anti-MICA Ab with an immunogenic protein might represent a novel therapeutic and prophylactic alternative to restore antitumor immunity. METHODS: We generated a highly immunogenic chimeric protein (BLS-MICA) consisting of human MICA fused to the lumazine synthase from Brucella spp (BLS) and used it to generate anti-MICA polyclonal Ab (pAb) and to investigate if these anti-MICA Ab can reinstate antitumor immunity in mice using two different mouse tumors engineered to express MICA. We also explored the underlying mechanisms of this expected therapeutic effect. RESULTS: Immunization with BLS-MICA and administration of anti-MICA pAb elicited by BLS-MICA significantly delayed the growth of MICA-expressing mouse tumors but not of control tumors. The therapeutic effect of immunization with BLS-MICA included scavenging of sMICA and the anti-MICA Ab-mediated ADCC, promoting heightened intratumoral M1/proinflammatory macrophage and antigen-experienced CD8+ T cell recruitment. CONCLUSIONS: Immunization with the chimeric protein BLS-MICA constitutes a useful way to actively induce therapeutic anti-MICA pAb that resulted in a reprogramming of the antitumor immune response towards an antitumoral/proinflammatory phenotype. Hence, the BLS-MICA chimeric protein constitutes a novel antitumor vaccine of potential application in patients with MICA-expressing tumors.


Assuntos
Anticorpos Monoclonais/farmacologia , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Linfoma/imunologia , Proteínas Recombinantes de Fusão/imunologia , Neoplasias da Bexiga Urinária/imunologia , Animais , Brucella/enzimologia , Feminino , Antígenos de Histocompatibilidade Classe I/genética , Linfoma/patologia , Linfoma/terapia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/imunologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/terapia
7.
Eur J Immunol ; 49(11): 2095-2102, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31334839

RESUMO

There is increasing evidence of the relevant connection and regulation between the gut and skin immune axis. In fact, oral administration of lipoteichoic acid (LTA) from Lactobacillus rhamnosus GG (LGG) prevents the development of UV-induced skin tumors in chronically exposed mice. Here we aim to evaluate whether this LTA is able to revert UV-induced immunosuppression as a mechanism involved in its anti-tumor effect and whether it has an immunotherapeutic effect against cutaneous squamous cell carcinoma. Using a mouse model of contact hypersensitivity, we demonstrate that LTA overcomes UV-induced skin immunosuppression. This effect was in part achieved by modulating the phenotype of lymph node resident dendritic cells (DC) and the homing of skin migratory DC. Importantly, oral LTA reduced significantly the growth of established skin tumors once UV radiation was discontinued, demonstrating that it has a therapeutic, besides the already demonstrated preventive antitumor effect. The data presented here strongly indicates that oral administration of LTA represents a promising immunotherapeutic approach for different conditions in which the skin immune system is compromised.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Lacticaseibacillus rhamnosus/química , Lipopolissacarídeos/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Ácidos Teicoicos/farmacologia , Raios Ultravioleta/efeitos adversos , Administração Oral , Animais , Antineoplásicos/isolamento & purificação , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/patologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Movimento Celular/efeitos da radiação , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/patologia , Células Dendríticas/efeitos da radiação , Dermatite de Contato/genética , Dermatite de Contato/imunologia , Dermatite de Contato/patologia , Feminino , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/patologia , Trato Gastrointestinal/efeitos da radiação , Lipopolissacarídeos/isolamento & purificação , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Linfonodos/patologia , Linfonodos/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Pele/efeitos dos fármacos , Pele/imunologia , Pele/patologia , Pele/efeitos da radiação , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Ácidos Teicoicos/isolamento & purificação
8.
Immunology ; 154(3): 510-521, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29377107

RESUMO

Ultraviolet radiation (UVr) promotes several well-known molecular changes, which may ultimately impact on health. Some of these effects are detrimental, like inflammation, carcinogenesis and immunosuppression. On the other hand, UVr also promotes vitamin D synthesis and other beneficial effects. We recently demonstrated that exposure to very low doses of UVr on four consecutive days [repetitive low UVd (rlUVd)] does not promote an inflammatory state, nor the recruitment of neutrophils or lymphocytes, as the exposure to a single high UV dose (shUVd) does. Moreover, rlUVd reinforce the epithelium by increasing antimicrobial peptides transcription and epidermal thickness. The aim of this study was to evaluate the adaptive immune response after shUVd and rlUVd, determining T-cell and B-cell responses. Finally, we challenged animals exposed to both irradiation procedures with Staphylococcus aureus to study the overall effects of both innate and adaptive immunity during a cutaneous infection. We observed, as expected, a marked suppression of T-cell and B-cell responses after exposure to an shUVd but a novel and significant increase in both specific responses after exposure to rlUVd. However, the control of the cutaneous S. aureus infection was defective in this last group, suggesting that responses against pathogens cannot be ruled out from isolated stimuli.


Assuntos
Imunidade Adaptativa/efeitos da radiação , Exposição à Radiação , Raios Ultravioleta , Animais , Formação de Anticorpos/imunologia , Formação de Anticorpos/efeitos da radiação , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/efeitos da radiação , Biomarcadores , Citocinas/metabolismo , Dermatite/imunologia , Dermatite/metabolismo , Dermatite/microbiologia , Dermatite/prevenção & controle , Modelos Animais de Doenças , Imunização , Imunofenotipagem , Masculino , Camundongos , Doses de Radiação , Infecções Cutâneas Estafilocócicas/imunologia , Infecções Cutâneas Estafilocócicas/microbiologia , Infecções Cutâneas Estafilocócicas/prevenção & controle , Staphylococcus aureus/imunologia , Staphylococcus aureus/efeitos da radiação , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/efeitos da radiação , Toxoide Tetânico/administração & dosagem , Toxoide Tetânico/imunologia
9.
Int J Mol Sci ; 18(6)2017 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-28598354

RESUMO

At the beginning, probiotics were used exclusively for gastrointestinal conditions. However, over the years, evidence has shown that probiotics exert systemic effects. In this review article, we will summarize recent reports that postulate probiotic treatment as an efficient one against skin pathologies, such as cancer, allergy, photoaging and skin infections. The focus will be restricted to oral probiotics that could potentially counteract the ultraviolet irradiation-induced skin alterations. Moreover, the possible underlying mechanisms by which probiotics can impact on the gut and exert their skin effects will be reviewed. Furthermore, how the local and systemic immune system is involved in the intestine-cutaneous crosstalk will be analyzed. In conclusion, this article will be divided into three core ideas: (a) probiotics regulate gut homeostasis; (b) gut and skin homeostasis are connected;


Assuntos
Gastroenteropatias/terapia , Probióticos/administração & dosagem , Dermatopatias/terapia , Animais , Gastroenteropatias/etiologia , Gastroenteropatias/metabolismo , Homeostase , Humanos , Sistema Imunitário , Imunomodulação , Intestinos/patologia , Intestinos/fisiologia , Microbiota , Neoplasias/epidemiologia , Neoplasias/etiologia , Neoplasias/metabolismo , Neoplasias/terapia , Nódulos Linfáticos Agregados/imunologia , Nódulos Linfáticos Agregados/metabolismo , Pele/imunologia , Pele/metabolismo , Pele/patologia , Dermatopatias/etiologia , Dermatopatias/metabolismo , Fenômenos Fisiológicos da Pele , Raios Ultravioleta/efeitos adversos
10.
Immunology ; 145(1): 82-93, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25438991

RESUMO

The modulatory effects of solar UV radiation on the immune system have been widely studied. As the skin is the main target of UV radiation, our purpose was to compare the impact on skin innate immunity of two contrasting ways to be exposed to sunlight. Hairless mice were UV irradiated with a single high UV dose simulating a harmful exposure, or with repetitive low UV doses simulating short occasional daily exposures. Skin samples were taken at different times after UV irradiation to evaluate skin histology, inflammatory cell recruitment, epidermal T-cell population and the mitochondrial function of epidermal cells. The transcriptional profiles of pro-inflammatory cytokines, chemokines, antimicrobial peptides and Toll-like receptors were evaluated by RT-PCR and ELISA in tissue homogenates. Finally, a lymphangiography was performed to assess modification in the lymphatic vessel system. A single high UV dose produces a deep inflammatory state characterized by the production of pro-inflammatory cytokines and chemokines that, in turn, induces the recruitment of neutrophils and macrophages into the irradiated area. On the other hand, repetitive low UV doses drive the skin to a photo-induced alert state in which there is no sign of inflammation, but the epithelium undergoes changes in thickness, the lymphatic circulation increases, and the transcription of antimicrobial peptides is induced.


Assuntos
Imunidade Inata/efeitos da radiação , Mediadores da Inflamação/imunologia , Pele/imunologia , Linfócitos T/imunologia , Raios Ultravioleta/efeitos adversos , Animais , Peptídeos Catiônicos Antimicrobianos/imunologia , Quimiocinas/imunologia , Relação Dose-Resposta à Radiação , Macrófagos/imunologia , Macrófagos/patologia , Camundongos , Infiltração de Neutrófilos/imunologia , Infiltração de Neutrófilos/efeitos da radiação , Neutrófilos/imunologia , Neutrófilos/patologia , Pele/patologia , Linfócitos T/patologia , Fatores de Tempo , Receptores Toll-Like/imunologia
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