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1.
Brain Behav Immun ; 118: 468-479, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38503395

RESUMO

Chronic lymphocytic leukaemia (CLL) is characterised by the clonal proliferation and accumulation of mature B-cells and is often treated with rituximab, an anti-CD20 monoclonal antibody immunotherapy. Rituximab often fails to induce stringent disease eradication, due in part to failure of antibody-dependent cellular cytotoxicity (ADCC) which relies on natural killer (NK)-cells binding to rituximab-bound CD20 on B-cells. CLL cells are diffusely spread across lymphoid and other bodily tissues, and ADCC resistance in survival niches may be due to several factors including low NK-cell frequency and a suppressive stromal environment that promotes CLL cell survival. It is well established that exercise bouts induce a transient relocation of NK-cells and B-cells into peripheral blood, which could be harnessed to enhance the efficacy of rituximab in CLL by relocating both target and effector cells together with rituximab in blood. In this pilot study, n = 20 patients with treatment-naïve CLL completed a bout of cycling 15 % above anaerobic threshold for âˆ¼ 30-minutes, with blood samples collected pre-, immediately post-, and 1-hour post-exercise. Flow cytometry revealed that exercise evoked a 254 % increase in effector (CD3-CD56+CD16+) NK-cells in blood, and a 67 % increase in CD5+CD19+CD20+ CLL cells in blood (all p < 0.005). NK-cells were isolated from blood samples pre-, and immediately post-exercise and incubated with primary isolated CLL cells with or without the presence of rituximab to determine specific lysis using a calcein-release assay. Rituximab-mediated cell lysis increased by 129 % following exercise (p < 0.001). Direct NK-cell lysis of CLL cells - independent of rituximab - was unchanged following exercise (p = 0.25). We conclude that exercise improved the efficacy of rituximab-mediated ADCC against autologous CLL cells ex vivo and propose that exercise should be explored as a means of enhancing clinical responses in patients receiving anti-CD20 immunotherapy.


Assuntos
Antineoplásicos , Leucemia Linfocítica Crônica de Células B , Humanos , Rituximab/farmacologia , Rituximab/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Projetos Piloto , Anticorpos Monoclonais Murinos/farmacologia , Anticorpos Monoclonais Murinos/uso terapêutico
2.
Front Oncol ; 13: 1244090, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37681023

RESUMO

Therapeutic monoclonal antibodies (mAbs) are standard care for many B-cell haematological cancers. The modes of action for these mAbs include: induction of cancer cell lysis by activating Fcγ-receptors on innate immune cells; opsonising target cells for antibody-dependent cellular cytotoxicity or phagocytosis, and/or triggering the classical complement pathway; the simultaneous binding of cancer cells with T-cells to create an immune synapse and activate perforin-mediated T-cell cytotoxicity against cancer cells; blockade of immune checkpoints to facilitate T-cell cytotoxicity against immunogenic cancer cell clones; and direct delivery of cytotoxic agents via internalisation of mAbs by target cells. While treatment regimens comprising mAb therapy can lead to durable anti-cancer responses, disease relapse is common due to failure of mAb therapy to eradicate minimal residual disease. Factors that limit mAb efficacy include: suboptimal effector cell frequencies, overt immune exhaustion and/or immune anergy, and survival of diffusely spread tumour cells in different stromal niches. In this review, we discuss how immunomodulatory changes arising from exposure to structured bouts of acute exercise might improve mAb treatment efficacy by augmenting (i) antibody-dependent cellular cytotoxicity, (ii) antibody-dependent cellular phagocytosis, (iii) complement-dependent cytotoxicity, (iv) T-cell cytotoxicity, and (v) direct delivery of cytotoxic agents.

3.
Blood Adv ; 5(8): 2229-2236, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33890978

RESUMO

Infection-related morbidity and mortality are increased in older patients with diffuse large B-cell lymphoma (DLBCL) compared with population-matched controls. Key predictive factors for infection-related hospitalization during treatment with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) and deaths as a result of infection in older patients during and after treatment with R-CHOP remain incompletely understood. For this study, 690 consecutively treated patients age 70 years or older who received full-dose or attenuated-dose R-CHOP treatment were analyzed for risk of infection-related hospitalization and infection-related death. Median age was 77 years, and 34.4% were 80 years old or older. Median follow-up was 2.8 years (range, 0.4-8.9 years). Patient and baseline disease characteristics were assessed in addition to intended dose intensity (IDI). Of all patients, 72% were not hospitalized with infection. In 331 patients receiving an IDI ≥80%, 33% were hospitalized with ≥1 infections compared with 23.3% of 355 patients receiving an IDI of <80% (odds ratio, 1.61; 95% confidence interval, 1.15-2.25; P = .006). An increased risk of infection-related admission was independently associated with IDI >80% across the whole cohort. Primary quinolone prophylaxis independently reduced infection-related admission. A total of 51 patients died as a result of infection. The 6-month, 12-month, 2-year, and 5-year cumulative incidences of infection-related death were 3.3%, 5.0%, 7.2%, and 11.1%, respectively. Key independent factors associated with infection-related death were an International Prognostic Index (IPI) score of 3 to 5, Cumulative Illness Rating Scale for Geriatrics (CIRS-G) score ≥6, and low albumin, which enabled us to generate a predictive risk score. We defined a smaller group (15%) of patients (IPI score of 0-2, albumin >36 g/L, CIRS-G score <6) in which no cases of infection-related deaths occurred at 5 years of follow-up. Whether patients at higher risk of infection-related death could be targeted with enhanced antimicrobial prophylaxis remains unknown and will require a randomized trial.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma Difuso de Grandes Células B , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/efeitos adversos , Doxorrubicina/efeitos adversos , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Morbidade , Rituximab/efeitos adversos , Rituximab/uso terapêutico , Vincristina/efeitos adversos
4.
Br J Haematol ; 187(2): 185-194, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31222719

RESUMO

Central nervous system (CNS) relapse following R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone) occurs in 2-5% of patents with diffuse large B-cell lymphoma (DLBCL). Many patients aged ≥70 years are unsuitable for high-dose methotrexate (HDMTX) prophylaxis and therefore often receive stand-alone intrathecal prophylaxis. The CNS international prognostic index (CNS-IPI) is a clinical CNS relapse risk score that has not specifically been validated in elderly patients. The value of CNS prophylaxis in patients aged ≥70 years remains uncertain. Data on 690 consecutively R-CHOP-treated DLBCL patients aged ≥70 years were collected across 8 UK centres (2009-2018). CNS prophylaxis was administered per physician preference. Median age was 77·2 years and median follow-up was 2·8 years. CNS-IPI was 1-3 in 60·1%, 4 in 23·8%, 5 in 13·0% and 6 in 3·3%. Renal and/or adrenal (R/A) involvement occurred in 8·8%. Two-year overall CNS relapse incidence was 2·6% and according to CNS-IPI, 1-3:0·8%, 4:3·6%, 5:3·8% and 6:21·8%. Two-year CNS relapse incidence for R/A was 10·0%. When excluding HDMTX (n = 31) patients, there remained no change in unadjusted/adjusted CNS relapse for intrathecal prophylaxis effect according to CNS-IPI. CNS-IPI is valid in elderly R-CHOP-treated DLBCL patients, with the highest risk in those with CNS-IPI 6 and R/A involvement. We observed no clear benefit for stand-alone intrathecal prophylaxis but observed an independent increased risk of infection-related admission during R-CHOP when intrathecal prophylaxis was administered.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias do Sistema Nervoso Central/mortalidade , Neoplasias do Sistema Nervoso Central/prevenção & controle , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/mortalidade , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Sistema Nervoso Central/patologia , Neoplasias do Sistema Nervoso Central/secundário , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Injeções Espinhais , Linfoma Difuso de Grandes Células B/patologia , Masculino , Metotrexato/administração & dosagem , Prednisona/administração & dosagem , Rituximab/administração & dosagem , Taxa de Sobrevida , Vincristina/administração & dosagem
6.
J Antimicrob Chemother ; 67(5): 1145-54, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22334603

RESUMO

OBJECTIVES: In this study, the objective was to determine the anti-inflammatory properties of CyP, a cyanobacterial lipopolysaccharide (LPS) antagonist, used in combination with antibiotic chemotherapy during infection of an in vitro meningitis model infected with Neisseria meningitidis (meningococcus). METHODS: Monocultures of human meningioma cells and meningioma-primary human macrophage co-cultures were infected with meningococci (10(2)-10(8) cfu/monolayer) or treated with isolated outer membranes or purified LPS (0.1-100 ng/monolayer) from N. meningitidis. CyP (1-20 µg/monolayer) was added at intervals from t = 0 to 4 h, with and without benzylpenicillin (1-20 µg/monolayer). The antagonistic effect of CyP and its adjunctive properties to benzylpenicillin administration was determined by measuring cytokine levels in culture supernatants after 24 h. RESULTS: CyP significantly inhibited (P < 0.05) the secretion of interleukin (IL)-6, IL-8, monocyte chemoattractant protein (MCP)-1 and RANTES ('regulated upon activation, normal T cell expressed and secreted') (overall reduction levels from 50% to >95%) by meningioma cell lines and meningioma-macrophage co-cultures challenged with either live meningococci or bacterial components. Inhibition was effective when CyP was added within 2 h of challenge (P < 0.05) and was still pronounced by 4 h. In the co-culture model, CyP alone partially inhibited IL-1ß secretion, but did not prevent tumour necrosis factor (TNF)-α secretion, whereas penicillin alone inhibited IL-1ß and TNF-α but conversely did not reduce MCP-1 and RANTES secretion. However, coadministration of CyP and penicillin in both models had an additive effect and restored the overall inhibitory profile. CONCLUSIONS: CyP inhibits cytokine production in an in vitro meningitis model and augments the anti-inflammatory response when combined with benzylpenicillin. Administration of an LPS antagonist with antibiotic merits consideration in the emergency treatment of patients presenting with meningococcal infection.


Assuntos
Antibacterianos/farmacologia , Citocinas/metabolismo , Fatores Imunológicos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Meningite Meningocócica/imunologia , Neisseria meningitidis/imunologia , Neisseria meningitidis/patogenicidade , Células Cultivadas , Técnicas de Cocultura , Células Epiteliais/imunologia , Humanos , Macrófagos/imunologia , Meningite Meningocócica/fisiopatologia , Penicilina G/farmacologia
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