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1.
Oncoimmunology ; 13(1): 2367777, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887372

RESUMO

T lymphocytes expressing CD57 and lacking costimulatory receptors CD27/CD28 have been reported to accumulate with aging, chronic infection, and cancer. These cells are described as senescent, with inability to proliferate but enhanced cytolytic and cytokine-producing capacity. However, robust functional studies on these cells taken directly from cancer patients are lacking. We isolated these T cells and their CD27/28+ counterparts from blood and tumor samples of 50 patients with previously untreated head and neck cancer. Functional studies confirmed that these cells have enhanced ability to degranulate and produce IFN-γ. They also retain the ability to proliferate, thus are not senescent. These data suggest that CD27/28-CD57+ CD8+ T cells are a subset of highly differentiated, CD45RA+ effector memory (TEMRA) cells with retained proliferative capacity. Patients with > 34% of these cells among CD8+ T cells in the blood had a higher rate of locoregional disease relapse, suggesting these cells may have prognostic significance.


Assuntos
Antígenos CD28 , Antígenos CD57 , Linfócitos T CD8-Positivos , Senescência Celular , Neoplasias de Cabeça e Pescoço , Humanos , Antígenos CD28/metabolismo , Antígenos CD57/metabolismo , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/metabolismo , Masculino , Pessoa de Meia-Idade , Feminino , Idoso , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Senescência Celular/imunologia , Interferon gama/metabolismo , Adulto , Proliferação de Células , Idoso de 80 Anos ou mais
2.
Cell Host Microbe ; 30(10): 1382-1400.e8, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36099922

RESUMO

Environmental pathogens move from ecological niches to mammalian hosts, requiring adaptation to dramatically different environments. Microbes that disseminate farther, including the fungal meningitis pathogen Cryptococcus neoformans, require additional adaptation to diverse tissues. We demonstrate that the formation of a small C. neoformans morphotype-called "seed" cells due to their colonizing ability-is critical for extrapulmonary organ entry. Seed cells exhibit changes in fungal cell size and surface expression that result in an enhanced macrophage update. Seed cell formation is triggered by environmental factors, including C. neoformans' environmental niche, and pigeon guano with phosphate plays a central role. Seed cells show the enhanced expression of phosphate acquisition genes, and mutants unable to acquire phosphate fail to adopt the seed cell morphotype. Additionally, phosphate can be released by tissue damage, potentially establishing a feed-forward loop of seed cell formation and dissemination. Thus, C. neoformans' size variation represent inducible morphotypes that change host interactions to facilitate microbe spread.


Assuntos
Criptococose , Cryptococcus neoformans , Adaptação Fisiológica , Animais , Columbidae , Criptococose/microbiologia , Cryptococcus neoformans/genética , Mamíferos , Fosfatos/metabolismo
3.
Lancet Oncol ; 22(12): 1777-1786, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34780711

RESUMO

BACKGROUND: The dependence of the adaptive immune system on circadian rhythm is an emerging field of study with potential therapeutic implications. We aimed to determine whether specific time-of-day patterns of immune checkpoint inhibitor infusions might alter melanoma treatment efficacy. METHODS: Melanoma Outcomes Following Immunotherapy (MEMOIR) is a longitudinal study of all patients with melanoma who received ipilimumab, nivolumab, or pembrolizumab, or a combination of these at a single tertiary cancer centre (Winship Cancer Institute of Emory University, Atlanta, GA, USA). For this analysis, we collected deidentified participant-level data from the MEMOIR database for adults (age ≥18 years) diagnosed with stage IV melanoma between 2012 and 2020. Those who received fewer than four infusions were excluded. Standard of care doses were used, with modifications at the treating physicians' discretion. The primary outcome was overall survival, defined as death from any cause and indexed from date of first infusion of immune checkpoint inhibitor. We calculated the association between overall survival and proportion of infusions of immune checkpoint inhibitors received after 1630 h (a composite time cutoff derived from seminal studies of the immune-circadian rhythm to represent onset of evening) using Cox regression and propensity score-matching on age, Eastern Cooperative Oncology Group performance status, serum lactate dehydrogenase concentration, and receipt of corticosteroids and radiotherapy. Treatment-related adverse events that led to change or discontinuation of immune checkpoint inhibitors were also assessed. FINDINGS: Between Jan 1, 2012, and Dec 31, 2020, 481 patients with melanoma received treatment with immune checkpoint inhibitors at the study centre, of whom 299 had stage IV disease and were included in this study; median follow-up was 27 months (IQR 14 to 47). In the complete unmatched sample, 102 (34%) patients were female and 197 (66%) were male, with a median age of 61 years (IQR 51 to 72). Every additional 20% of infusions of immune checkpoint inhibitors received after 1630 h (among all infusions received by a patient) conferred an overall survival hazard ratio (HR) of 1·31 (95% CI 1·00 to 1·71; p=0·046). A propensity score-matched analysis of patients who did (n=73) and did not (n=73) receive at least 20% of their infusions of immune checkpoint inhibitors after 1630 h (54 [37%] of 146 patients were women and 92 [63%] were men, with a median age of 58 years [IQR 48 to 68]) showed that having at least 20% of infusions in the evening was associated with shorter overall survival (median 4·8 years [95% CI 3·9 to not estimable] vs not reached; HR 2·04 [1·04 to 4·00; p=0·038]). This result remained robust to multivariable proportional hazards adjustment with (HR 1·80 [1·08 to 2·98; p=0·023]) and without (2·16 [1·10 to 4·25; p=0·025]) inclusion of the complete unmatched study sample. The most common adverse events were colitis (54 [18%] of 299 patients), hepatitis (27 [9%]), and hypophysitis (15 [5%]), and there were no treatment-related deaths. INTERPRETATION: Our findings are in line with an increasing body of evidence that adaptive immune responses are less robust when initially stimulated in the evening than if stimulated in the daytime. Although prospective studies of the timing of immune checkpoint inhibitor infusions are warranted, efforts towards scheduling infusions before mid-afternoon could be considered in the multidisciplinary management of advanced melanoma. FUNDING: National Institutes of Health, American Society for Radiation Oncology and Melanoma Research Alliance, and Winship Cancer Institute.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ritmo Circadiano , Imunoterapia/mortalidade , Melanoma/mortalidade , Neoplasias Cutâneas/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Feminino , Seguimentos , Humanos , Infusões Intravenosas , Ipilimumab/administração & dosagem , Estudos Longitudinais , Masculino , Melanoma/tratamento farmacológico , Melanoma/patologia , Pessoa de Meia-Idade , Nivolumabe/administração & dosagem , Prognóstico , Pontuação de Propensão , Estudos Retrospectivos , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Taxa de Sobrevida
4.
Elife ; 92020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32367801

RESUMO

Invasive fungal infections cause 1.6 million deaths annually, primarily in immunocompromised individuals. Mortality rates are as high as 90% due to limited treatments. The azole class antifungal, fluconazole, is widely available and has multi-species activity but only inhibits growth instead of killing fungal cells, necessitating long treatments. To improve treatment, we used our novel high-throughput method, the overlap2 method (O2M) to identify drugs that interact with fluconazole, either increasing or decreasing efficacy. We identified 40 molecules that act synergistically (amplify activity) and 19 molecules that act antagonistically (decrease efficacy) when combined with fluconazole. We found that critical frontline beta-lactam antibiotics antagonize fluconazole activity. A promising fluconazole-synergizing anticholinergic drug, dicyclomine, increases fungal cell permeability and inhibits nutrient intake when combined with fluconazole. In vivo, this combination doubled the time-to-endpoint of mice with Cryptococcus neoformans meningitis. Thus, our ability to rapidly identify synergistic and antagonistic drug interactions can potentially alter the patient outcomes.


Individuals with weakened immune systems ­ such as recipients of organ transplants ­ can fall prey to illnesses caused by fungi that are harmless to most people. These infections are difficult to manage because few treatments exist to fight fungi, and many have severe side effects. Antifungal drugs usually slow the growth of fungi cells rather than kill them, which means that patients must remain under treatment for a long time, or even for life. One way to boost efficiency and combat resistant infections is to combine antifungal treatments with drugs that work in complementary ways: the drugs strengthen each other's actions, and together they can potentially kill the fungus rather than slow its progression. However, not all drug combinations are helpful. In fact, certain drugs may interact in ways that make treatment less effective. This is particularly concerning because people with weakened immune systems often take many types of medications. Here, Wambaugh et al. harnessed a new high-throughput system to screen how 2,000 drugs (many of which already approved to treat other conditions) affected the efficiency of a common antifungal called fluconazole. This highlighted 19 drugs that made fluconazole less effective, some being antibiotics routinely used to treat patients with weakened immune systems. On the other hand, 40 drugs boosted the efficiency of fluconazole, including dicyclomine, a compound currently used to treat inflammatory bowel syndrome. In fact, pairing dicyclomine and fluconazole more than doubled the survival rate of mice with severe fungal infections. The combined treatment could target many species of harmful fungi, even those that had become resistant to fluconazole alone. The results by Wambaugh et al. point towards better treatments for individuals with serious fungal infections. Drugs already in circulation for other conditions could be used to boost the efficiency of fluconazole, while antibiotics that do not decrease the efficiency of this medication should be selected to treat at-risk patients.


Assuntos
Antifúngicos/uso terapêutico , Antagonismo de Drogas , Sinergismo Farmacológico , Micoses/tratamento farmacológico , Animais , Antifúngicos/farmacologia , Criptococose/tratamento farmacológico , Cryptococcus neoformans/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Fluconazol/farmacologia , Fluconazol/uso terapêutico , Ensaios de Triagem em Larga Escala , Humanos , Meningite Criptocócica/tratamento farmacológico , Camundongos , Relação Estrutura-Atividade
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