RESUMO
ABSTRACT: Patients with multiple myeloma (MM) treated with B-cell maturation antigen (BCMA)-specific chimeric antigen receptor (CAR) T cells usually relapse with BCMA+ disease, indicative of CAR T-cell suppression. CD200 is an immune checkpoint that is overexpressed on aberrant plasma cells (aPCs) in MM and is an independent negative prognostic factor for survival. However, CD200 is not present on MM cell lines, a potential limitation of current preclinical models. We engineered MM cell lines to express CD200 at levels equivalent to those found on aPCs in MM and show that these are sufficient to suppress clinical-stage CAR T-cells targeting BCMA or the Tn glycoform of mucin 1 (TnMUC1), costimulated by 4-1BB and CD2, respectively. To prevent CD200-mediated suppression of CAR T cells, we compared CRISPR-Cas9-mediated knockout of the CD200 receptor (CD200RKO), to coexpression of versions of the CD200 receptor that were nonsignaling, that is, dominant negative (CD200RDN), or that leveraged the CD200 signal to provide CD28 costimulation (CD200R-CD28 switch). We found that the CD200R-CD28 switch potently enhanced the polyfunctionality of CAR T cells, and improved cytotoxicity, proliferative capacity, CAR T-cell metabolism, and performance in a chronic antigen exposure assay. CD200RDN provided modest benefits, but surprisingly, the CD200RKO was detrimental to CAR T-cell activity, adversely affecting CAR T-cell metabolism. These patterns held up in murine xenograft models of plasmacytoma, and disseminated bone marrow predominant disease. Our findings underscore the importance of CD200-mediated immune suppression in CAR T-cell therapy of MM, and highlight a promising approach to enhance such therapies by leveraging CD200 expression on aPCs to provide costimulation via a CD200R-CD28 switch.
Assuntos
Imunoterapia Adotiva , Mieloma Múltiplo , Humanos , Camundongos , Animais , Mieloma Múltiplo/metabolismo , Antígenos CD28/metabolismo , Linfócitos T , Antígeno de Maturação de Linfócitos B/metabolismo , Recidiva Local de Neoplasia/metabolismoRESUMO
Background: Little is known about the dynamics of SARS-CoV-2 antigen burden in respiratory samples in different patient populations at different stages of infection. Current rapid antigen tests cannot quantitate and track antigen dynamics with high sensitivity and specificity in respiratory samples. Methods: We developed and validated an ultra-sensitive SARS-CoV-2 antigen assay with smartphone readout using the Microbubbling Digital Assay previously developed by our group, which is a platform that enables highly sensitive detection and quantitation of protein biomarkers. A computer vision-based algorithm was developed for microbubble smartphone image recognition and quantitation. A machine learning-based classifier was developed to classify the smartphone images based on detected microbubbles. Using this assay, we tracked antigen dynamics in serial swab samples from COVID patients hospitalized in ICU and immunocompromised COVID patients. Results: The limit of detection (LOD) of the Microbubbling SARS-CoV-2 Antigen Assay was 0.5 pg/mL (10.6 fM) recombinant nucleocapsid (N) antigen or 4000 copies/mL inactivated SARS-CoV-2 virus in nasopharyngeal (NP) swabs, comparable to many rRT-PCR methods. The assay had high analytical specificity towards SARS-CoV-2. Compared to EUA-approved rRT-PCR methods, the Microbubbling Antigen Assay demonstrated a positive percent agreement (PPA) of 97% (95% confidence interval (CI), 92-99%) in symptomatic individuals within 7 days of symptom onset and positive SARS-CoV-2 nucleic acid results, and a negative percent agreement (NPA) of 97% (95% CI, 94-100%) in symptomatic and asymptomatic individuals with negative nucleic acid results. Antigen positivity rate in NP swabs gradually decreased as days-after-symptom-onset increased, despite persistent nucleic acid positivity of the same samples. The computer vision and machine learning-based automatic microbubble image classifier could accurately identify positives and negatives, based on microbubble counts and sizes. Total microbubble volume, a potential marker of antigen burden, correlated inversely with Ct values and days-after-symptom-onset. Antigen was detected for longer periods of time in immunocompromised patients with hematologic malignancies, compared to immunocompetent individuals. Simultaneous detectable antigens and nucleic acids may indicate the presence of replicating viruses in patients with persistent infections. Conclusions: The Microbubbling SARS-CoV-2 Antigen Assay enables sensitive and specific detection of acute infections, and quantitation and tracking of antigen dynamics in different patient populations at various stages of infection. With smartphone compatibility and automated image processing, the assay is well-positioned to be adapted for point-of-care diagnosis and to explore the clinical implications of antigen dynamics in future studies.
Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Imunoterapia Adotiva , Terapia de Alvo Molecular , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/terapia , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/diagnóstico , Recidiva , Retratamento , Resultado do TratamentoRESUMO
PURPOSE: Single-cycle melphalan 200 mg/m2 and autologous hematopoietic cell transplantation (AHCT) followed by lenalidomide (len) maintenance have improved progression-free survival (PFS) and overall survival (OS) for transplantation-eligible patients with multiple myeloma (MM). We designed a prospective, randomized, phase III study to test additional interventions to improve PFS by comparing AHCT, tandem AHCT (AHCT/AHCT), and AHCT and four subsequent cycles of len, bortezomib, and dexamethasone (RVD; AHCT + RVD), all followed by len until disease progression. PATIENTS AND METHODS: Patients with symptomatic MM within 12 months from starting therapy and without progression who were age 70 years or younger were randomly assigned to AHCT/AHCT + len (n = 247), AHCT + RVD + len (n = 254), or AHCT + len (n = 257). The primary end point was 38-month PFS. RESULTS: The study population had a median age of 56 years (range, 20 to 70 years); 24% of patients had high-risk MM, 73% had a triple-drug regimen as initial therapy, and 18% were in complete response at enrollment. The 38-month PFS rate was 58.5% (95% CI, 51.7% to 64.6%) for AHCT/AHCT + len, 57.8% (95% CI, 51.4% to 63.7%) for AHCT + RVD + len, and 53.9% (95% CI, 47.4% to 60%) for AHCT + len. For AHCT/AHCT + len, AHCT + RVD + len, and AHCT + len, the OS rates were 81.8% (95% CI, 76.2% to 86.2%), 85.4% (95% CI, 80.4% to 89.3%), and 83.7% (95% CI, 78.4% to 87.8%), respectively, and the complete response rates at 1 year were 50.5% (n = 192), 58.4% (n = 209), and 47.1% (n = 208), respectively. Toxicity profiles and development of second primary malignancies were similar across treatment arms. CONCLUSION: Second AHCT or RVD consolidation as post-AHCT interventions for the up-front treatment of transplantation-eligible patients with MM did not improve PFS or OS. Single AHCT and len should remain as the standard approach for this population.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bortezomib/administração & dosagem , Dexametasona/administração & dosagem , Transplante de Células-Tronco Hematopoéticas , Lenalidomida/administração & dosagem , Mieloma Múltiplo/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bortezomib/efeitos adversos , Quimioterapia de Consolidação , Dexametasona/efeitos adversos , Progressão da Doença , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Lenalidomida/efeitos adversos , Quimioterapia de Manutenção , Masculino , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Agonistas Mieloablativos/administração & dosagem , Intervalo Livre de Progressão , Estudos Prospectivos , Indução de Remissão , Reoperação , Fatores de Tempo , Transplante Autólogo , Estados Unidos , Adulto JovemRESUMO
BACKGROUND: High-dose melphalan with autologous stem cell support improves survival for patients with myeloma. For selected patients, we have been using a protocol of short hospitalization, discharging patients to home with careful outpatient monitoring in the office, which we hypothesized would reduce complications and utilization of inpatient beds. METHODS: We reviewed 301 initial autologous transplants for myeloma, categorized as brief stay (≤ 4 days, 82 patients) or prolonged stay (≥ 5 days, 219 patients). Selection for a brief stay was determined by clinical characteristics, availability of caregivers at home, distance from our medical center, and patient preference. RESULTS: Within the brief stay population, 67% required readmission before day + 100, but this group still had fewer cumulative hospital days (9 vs. 18, P < .0001). There were fewer documented infections among brief stay patients (22% vs. 46% P < .001) and fewer admissions to intensive care units (0% vs. 5.9%, P = .02). The groups had similar rates of bleeding (1.2% vs. 1.4% P = 1.0) and thrombosis (3.7% vs. 4.6% P = 1.0). No patients in the brief stay group died within 100 days, compared with mortality of 1.8% (P = .6) in the prolonged stay group. CONCLUSION: Carefully selected patients receiving an autologous stem cell transplant for treatment of myeloma can be managed with a brief initial hospitalization and outpatient follow-up, with low morbidity and mortality.