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1.
MAbs ; 15(1): 2212673, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37216961

RESUMO

Immune checkpoint inhibitors that overcome T cell suppressive mechanisms in tumors have revolutionized the treatment of cancer but are only efficacious in a small subset of patients. Targeting suppressive mechanisms acting on innate immune cells could significantly improve the incidence of clinical response by facilitating a multi-lineage response against the tumor involving both adaptive and innate immune systems. Here, we show that intra-tumoral interleukin (IL)-38 expression is a feature of a large frequency of head and neck, lung and cervical squamous cancers and correlates with reduced immune cell numbers. We generated IMM20324, an antibody that binds human and mouse IL-38 proteins and inhibits the binding of IL-38 to its putative receptors, interleukin 1 receptor accessory protein-like 1 (IL1RAPL) and IL-36R. In vivo, IMM20324 demonstrated a good safety profile, delayed tumor growth in a subset of mice in an EMT6 syngeneic model of breast cancer, and significantly inhibited tumor expansion in a B16.F10 melanoma model. Notably, IMM20324 treatment resulted in the prevention of tumor growth following re-implantation of tumor cells, indicating the induction of immunological memory. Furthermore, exposure of IMM20324 correlated with decreased tumor volume and increased levels of intra-tumoral chemokines. Together, our data suggest that IL-38 is expressed in a high frequency of cancer patients and allows tumor cells to suppress anti-tumor immunity. Blockade of IL-38 activity using IMM20324 can re-activate immunostimulatory mechanisms in the tumor microenvironment leading to immune infiltration, the generation of tumor-specific memory and abrogation of tumor growth.


Assuntos
Melanoma Experimental , Linfócitos T , Humanos , Camundongos , Animais , Melanoma Experimental/tratamento farmacológico , Memória Imunológica , Microambiente Tumoral , Linhagem Celular Tumoral , Interleucinas
2.
Sci Immunol ; 7(75): eabl9943, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-35771946

RESUMO

Monoclonal antibodies are an efficacious therapy against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, rapid viral mutagenesis led to escape from most of these therapies, outlining the need for an antibody cocktail with a broad neutralizing potency. Using an unbiased interrogation of the memory B cell repertoire of patients with convalescent COVID-19, we identified human antibodies with broad antiviral activity in vitro and efficacy in vivo against all tested SARS-CoV-2 variants of concern, including Delta and Omicron BA.1 and BA.2. Here, we describe an antibody cocktail, IMM-BCP-01, that consists of three patient-derived broadly neutralizing antibodies directed at nonoverlapping surfaces on the SARS-CoV-2 Spike protein. Two antibodies, IMM20184 and IMM20190, directly blocked Spike binding to the ACE2 receptor. Binding of the third antibody, IMM20253, to its cryptic epitope on the outer surface of RBD altered the conformation of the Spike Trimer, promoting the release of Spike monomers. These antibodies decreased Omicron SARS-CoV-2 infection in the lungs of Syrian golden hamsters in vivo and potently induced antiviral effector response in vitro, including phagocytosis, ADCC, and complement pathway activation. Our preclinical data demonstrated that the three-antibody cocktail IMM-BCP-01 could be a promising means for preventing or treating infection of SARS-CoV-2 variants of concern, including Omicron BA.1 and BA.2, in susceptible individuals.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Antivirais , Cricetinae , Humanos , Glicoproteína da Espícula de Coronavírus/genética
3.
Chem Res Toxicol ; 27(8): 1450-7, 2014 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-25055050

RESUMO

Xenobiotics may activate the estrogen receptor, resulting in alteration of normal endocrine functions in animals and humans. Consequently, this necessitates development of assay end points capable of identifying estrogenic xenobiotics. In the present study, we screened the potential estrogenicity of chemicals via their ability to induce vitellogenin (VTG) expression in cultured primary hepatocytes from male trout. A routine method for VTG detection measures the secretion of the protein by enzyme-linked immunosorbent assay (ELISA) in freshly isolated trout hepatocytes. However, this lengthy (6 days) culturing procedure requires that hepatocyte isolation is performed each time the assay is run. We optimized this methodology by investigating the utility of cryopreserved hepatocytes, shortening the incubation time, performing a quantitative real-time PCR (qPCR) method for VTG quantification, and verifying the model system with reference chemicals 17ß-estradiol, estrone, diethylstilbestrol, hexestrol, genistein, and a negative control, corticosterone. To test the performance of both freshly isolated and cryopreserved hepatocytes, mRNA was collected from hepatocytes following 24 h treatment for VTG gene expression analysis, whereas cell culture media was collected for a VTG ELISA 96 h post-treatment. EC50 values were obtained for each reference chemical except for corticosterone, which exhibited no induction of VTG gene or protein level. Our results show linear concordance between ELISA and qPCR detection methods. Although there was approximately 50% reduction in VTG inducibility following cryopreservation, linear concordance of EC50 values was found between freshly isolated and cryopreserved hepatocytes, indicating that cryopreservation does not alter the functional assessment of estrogen receptor activation and therefore VTG expression. These studies demonstrate that qPCR is a sensitive and specific method for detecting VTG gene expression that can be used together with cryopreserved trout hepatocytes for screening estrogenic chemicals, resulting in a reduction of the time required to perform the assay and enabling greater access to the model system through the approach of cryopreservation.


Assuntos
Disruptores Endócrinos/toxicidade , Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Vitelogeninas/metabolismo , Animais , Células Cultivadas , Disruptores Endócrinos/química , Ensaio de Imunoadsorção Enzimática , Hepatócitos/citologia , Hepatócitos/metabolismo , Masculino , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Truta , Vitelogeninas/genética , Xenobióticos/toxicidade
5.
J Neurosci Methods ; 185(1): 70-5, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19765611

RESUMO

Histamine H(3) receptor antagonists have been proposed as a novel approach to the treatment of cognitive, attentional, and sleep disorders. It is apparent that H(3) receptor antagonists produce in vivo effects in preclinical animal models of central diseases across a wide dose range. In order to characterize the relationship between efficacy in the preclinical models and H(3) receptor occupancy, a brain slice receptor autoradiography method was used. Brain slice receptor autoradiography requires less in vitro tissue processing, preserves brain structure, and provides anatomical localization of compound in the brain. Consistent with H(3) receptor distribution, in vitro autoradiography experiments demonstrated specific binding of [(3)H]NAMH (N-alpha-methylhistamine) in rat cortex, and other brain regions, but not in cerebellum. Ex vivo H(3)R brain slice autoradiography was able to detect H(3) receptor occupancy by reference antagonists at doses lower than previously found using a homogenate assay format. The method is relatively quick with image acquisition on a beta-imager and is capable of detecting receptor occupancy in different brain regions simultaneously. Furthermore, the increased sensitivity should be useful in providing dosing guidelines for H(3) antagonists in both preclinical and clinical settings.


Assuntos
Autorradiografia/métodos , Química Encefálica/fisiologia , Antagonistas dos Receptores Histamínicos/análise , Receptores Histamínicos H3/efeitos dos fármacos , Animais , Ligação Competitiva/efeitos dos fármacos , Ligação Competitiva/fisiologia , Bioensaio , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Antagonistas dos Receptores Histamínicos/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Masculino , Técnicas de Cultura de Órgãos , Valor Preditivo dos Testes , Ratos , Ratos Sprague-Dawley , Receptores Histamínicos H3/metabolismo , Valores de Referência , Sensibilidade e Especificidade
6.
Int J Sports Physiol Perform ; 2(2): 182-91, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19124905

RESUMO

BACKGROUND: Despite the thermal challenge of demanding workloads performed in high cabin temperatures while wearing heavy heat-retardant clothing, information on physiological responses to racing V8 Supercars in hot conditions is not readily available. PURPOSE: To describe the thermal, cardiovascular, and perceptual strain on V8 Supercar drivers competing in hot conditions. METHODS: Thermal strain was indicated by body-core temperature using an ingested thermosensitive pill. Cardiovascular strain was assessed from heart rate, hydration status, and sweat rate. Perceptual strain was estimated from self-rated thermal sensation, thermal discomfort (modified Gagge scales), perceived exertion (Borg scale), and perceptual strain index. RESULTS: Prerace body-core temperatures were (mean +/- SD) 37.7 degrees C +/- 0.4 degrees C (range 37.0 degrees C to 38.2 degrees C), rising to 39.0 degrees C +/- 0.4 degrees C (range 38.4 degrees C to 39.7 degrees C) postrace. Driver heart rates were >160 and >170 beats/min for 85.3% and 46.7% of racing, respectively. Sweat rates were 1.06 +/- 0.12 L/h or 13.4 +/- 1.2 mL . kg-1 . h-1, and postrace dehydration was 0.6% +/- 0.6% of prerace body mass. Drivers rated thermal sensation as hot (10.3 +/- 0.9), thermal discomfort as uncomfortable (3.1 +/- 1.0), and perceived exertion as very hard to very, very hard (8.7 +/- 1.7) after the races. Overall physiological and perceptual strain were 7.4 +/- 1.0 and 7.1 +/- 1.2, respectively. CONCLUSIONS: Despite the use of cooling, V8 Supercar drivers endure thermal, cardiovascular, and perceptual strain during brief driving bouts in hot conditions.


Assuntos
Adaptação Fisiológica/fisiologia , Condução de Veículo , Regulação da Temperatura Corporal , Transtornos de Estresse por Calor/prevenção & controle , Temperatura Alta , Esportes/fisiologia , Adulto , Comportamento Competitivo , Humanos , Masculino , Telemetria
7.
J Sports Sci Med ; 2(4): 158-62, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24688277

RESUMO

The main finding of this study was that for heat acclimatised athletes, there was no significant difference (p=0.58) in anaerobic capacity for temperate (21.8 ± 0.5 °C; 52 ± 5 % relative humidity) compared with warm conditions (29.6 ± 0.5 °C; 51 ± 9 % relative humidity). Anaerobic capacity was estimated using the maximal accumulated oxygen deficit (MAOD) during constant intensity cycling at 120% peak rate of O2 consumption until exhaustion. This yielded mean MAOD values of 3.3 ± 0.9 and 3.5 ± 1.1 L for temperate and warm conditions, respectively. Peak post-exercise lactate values of 14.7 ± 3.8 and 14.4 ± 4.5 mmol·L(-1) for temperate and warm conditions respectively, were also not significantly different (p=0.72). Time to exhaustion (TTE) was similarly unchanged (p=0.56), being 175 ± 19 and 170 ± 18 s for temperate and warm conditions, respectively. These results suggest that the MAOD remains a valid test throughout environmental temperatures for the range of 20-30 °C when used with heat acclimatised athletes.

8.
J Neurochem ; 82(6): 1424-34, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12354290

RESUMO

Overexpression of gp120, the major coat protein of the HIV-1 virus, in central glial cells, or treatment of neurons with gp120 in culture, produces apoptotic neuronal death. Here we demonstrate that CEP-1347 (KT7515), an inhibitor of mixed lineage kinase 3 (MLK3), an upstream activator of JNK, inhibits gp120IIIB-induced apoptosis of hippocampal neurons. Furthermore, expression of wild type MLK3 in hippocampal pyramidal neurons enhanced gp120IIIB-induced neurotoxicity, whereas expression of a dominant negative MLK3 protected neurons from the toxic effects of the glycoprotein. These results indicate a role for MLK3 signaling in gp120IIIB-induced neuronal death, and suggest potential clinical utility of CEP-1347 in inhibiting the progression of AIDS dementia.


Assuntos
Proteína gp120 do Envelope de HIV/toxicidade , HIV-1 , MAP Quinase Quinase Quinases/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Animais , Apoptose/efeitos dos fármacos , Antígenos CD4/farmacologia , Carbazóis/farmacologia , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Genes Dominantes , Hipocampo , Indóis/farmacologia , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/genética , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Neuroglia/citologia , Neurônios/citologia , Fármacos Neuroprotetores , Células Piramidais/citologia , Células Piramidais/efeitos dos fármacos , Células Piramidais/metabolismo , Ratos , MAP Quinase Quinase Quinase 11 Ativada por Mitógeno
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