CS1 Expression Pattern in NK Cells and Correlated Factors in Plasma Cell dyscrasias: Implications for Elotuzumab Therapy and CAR-T Efficacy.

Treatment with elotuzumab alone has no discernible antitumor effect and progress in chimeric antigen receptor T cells (CAR-T) therapy targeting CS1 is relatively slow. A retrospective analysis was performed on 236 patients with multiple myeloma (MM) and 30 patients with other plasma cell dyscrasias (PCDs). CS1 expression in NK cells, lymphocytes, and monoclonal plasma cells was assessed using multiparameter flow cytometry. Furthermore, new explorations were undertaken regarding the antitumor applications of elotuzumab. Patients with MM had significantly higher CS1 expression levels in plasma cells than other patients with PCDs, with no significant differences between lymphocytes and NK cells. In both patients with MM and other PCDs, CS1 expression was significantly higher in plasma cells than in NK cells and lymphocytes. Univariate and multivariate analyses revealed a significant correlation between CS1 expression in plasma (r = 0.60; P < 0.001) and NK (r = 0.79; P < 0.001) cells. Factors such as cytogenetic abnormalities, disease progression, and survival were not associated with CS1 expression in NK cells. Moreover, this study showed that elotuzumab strongly increases the cytotoxicity of NK cells against non-plasma and plasma tumor cells independent of their CS1 expression level. This underscores the potential of elotuzumab in combination with NK cells as an effective therapeutic strategy against a broad spectrum of tumor types.

Case report: Light-chain amyloidosis responsive to selinexor in combination with daratumumab and dexamethasone (SDd) therapy.

The outcome of AL amyloidosis remains poor, particularly in patients with advanced organ involvement which takes long time to recovery. We conducted an observational study of two patients with AL amyloidosis treated with SDd regimen. Both patients successfully achieved significant hematological and organ responses without severe adverse events, and the time to organ response was remarkably shorter than previously reported. Notably, an over 15% reduction in interventricular septal thickness (IVST) was observed in patient#2 within 6 months. Up to now, SDd therapy has not been previously reported in AL amyloidosis and may be a promising option for these patients.

High-multiplex single-cell imaging analysis reveals tumor immune contexture associated with clinical outcomes after CAR T cell therapy.

Chimeric antigen receptor (CAR) T cell therapy has made great progress in treating lymphoma, yet patient outcomes still vary greatly. The lymphoma microenvironment may be an important factor in the efficacy of CAR T therapy. In this study, we designed a highly multiplexed imaging mass cytometry (IMC) panel to simultaneously quantify 31 biomarkers from 13 patients with relapsed/refractory diffuse large B cell lymphoma (DLBCL) who received CAR19/22 T cell therapy. A total of 20 sections were sampled before CAR T cell infusion or after infusion when relapse occurred. A total of 35 cell clusters were identified, annotated, and subsequently redefined into 10 metaclusters. The CD4+ T cell fraction was positively associated with remission duration. Significantly higher Ki67, CD57, and TIM3 levels and lower CD69 levels in T cells, especially the CD8+/CD4+ Tem and Te cell subsets, were seen in patients with poor outcomes. Cellular neighborhood containing more immune cells was associated with longer remission. Fibroblasts and vascular endothelial cells resided much closer to tumor cells in patients with poor response and short remission after CAR T therapy. Our work comprehensively and systematically dissects the relationship between cell composition, state, and spatial arrangement in the DLBCL microenvironment and the outcomes of CAR T cell therapy, which is beneficial to predict CAR T therapy efficacy.

Value of preoperative controlling nutritional status score in prognosis of patients with high-risk factors for early-stage cervical cancer.

Objective: To investigate whether the preoperative controlling nutritional status (COUNT) score is a prognostic factor of patients with high-risk factors for early-stage cervical cancer after surgery and concurrent chemoradiotherapy (CCRT). Methods: This was a retrospective study. From July 2017 to March 2021, a total of 354 patients with histologically confirmed FIGO stage IB-IIA cervical cancer undergoing surgery and postoperative CCRT were included at Hunan University of Medicine General Hospital, China. According to receiver operating characteristic (ROC) curve analysis, the patients were divided into a low CONUT score (< 3) group and a high CONUT score (≥ 3) group. Overall survival (OS) was used as the primary outcome measure and disease-free survival (DFS) as the secondary outcome measure. Results: Among the 354 patients, 239(67.5%) were included in the low CONUT score group and 115 (32.5%) in the high CONUT score group. The 3, 5 and 10-year OS rates in the low CONUT score group and high CONUT score group were respectively presenting statistically significant differences (p<0.001). The 3, 5 and 10-year DFS rates in the low CONUT score group and in the high CONUT score group were respectively with statistically significant differences (p<0.001). Multivariate Cox regression analysis showed that CONUT score, histological type, PNI and lymph node metastasis were all independent predictors for OS and DFS (all p<0.05). Conclusion: High preoperative CONUT score indicates poor prognosis of patients with high-risk factors for early-stage cervical cancer after surgery and postoperative CCRT. In clinical practice, consolidation chemotherapy is recommended for patients with high CONUT scores.

A novel two-step administration of XPO-1 inhibitor may enhance the effect of anti-BCMA CAR-T in relapsed/refractory extramedullary multiple myeloma.

BACKGROUND: Extramedullary disease usually implies a dismal outcome in relapsed/refractory multiple myeloma patients, and requires novel treatment approaches. We designed a trial using Selinexor, a nuclear export protein 1 inhibitor, together with anti-B cell maturation antigen (BCMA) chimeric antigen receptor (CAR)-T cell product CT103A to treat these patients, and describe the first two cases in this report. METHODS: Selinexor was administered with a novel two-step schedule in bridging therapy and in maintenance. The clinical responses and adverse events were recorded after CAR-T infusion and Selinexor administration. In vitro analysis of the influence of Selinexor on CAR-T cell function was performed using myeloma cell lines. RESULTS: After infusion, both patients achieved stringent complete remission (sCR), and were maintained in sCR at data-cutoff, with survival over 13 and 10 months, respectively. Neither immune effector cell-associated neurotoxicity syndrome nor over grade 2 cytokine release syndrome was observed. Meanwhile, the patients showed good tolerance to the combination. In addition, we demonstrated that low dose of Selinexor could upregulate the expression of BCMA on plasma cell lines and subsequently enhance the function of CAR-T cell in vitro. CONCLUSIONS: The combination of Selinexor and CT103A exerts preliminary synergistic effect, and can be developed as a promising strategy for relapsed/refractory extramedullary myeloma.

Assessment and predictive ability of the absolute neutrophil count in peripheral blood for in vivo CAR T cells expansion and CRS.

BACKGROUND: Chimeric antigen receptor (CAR) T cell therapy is an advanced and effective immunotherapy for relapsed or refractory B-cell malignancies. High expansion of CAR T cells in vivo and durable antitumor activity indicate a persistent therapeutic response. However, this treatment is linked to a high frequency of adverse events, such as cytokine release syndrome (CRS), which affects its efficacy and can even be life-threatening. At present, a variety of markers associated with clinical response and treatment toxicity after CAR T cells infusion have been reported. Although these biomarkers can act as effective indicators reflecting CAR T cells expansion as well as CRS, they fail to predict the expansion rate of CAR T cells. Hence, further investigation is urgent to find a new biomarker to fill this void. METHODS: We analyzed the association between the absolute neutrophil count (ANC) and CAR expansion and CRS in 45 patients with B-cell malignancies from two clinical trials. We proposed that ANC could be a practical biomarker for CAR T cells expansion and CRS, and conducted a feasibility analysis on its predictive ability. RESULTS: In this study, 17 B-cell hematological malignancy patients with anti-B-cell maturation antigen CAR-treated and 28 with CAR19/22 T-cell-treated were enrolled and divided into an ANC-absence group and an ANC-presence group. The results showed that ANC absence correlated positively with CAR expansion and the expansion rate. The ANC can be used as a predictive marker for CAR T cells expansion. Moreover, the patients with ANC absence experienced a more severe CRS, and ANC performed a predictive ability for CRS. In addition, the peak serum concentration of several cytokines involved in CRS was higher in patients with ANC absence. CONCLUSION: Thus, we suggest ANC as an evaluative and predictive biomarker for CAR expansion and CRS during CAR T cell therapy, which can help to maximize clinical efficacy, reduce treatment-related toxicity and prolong survival.

Recovery-model: A model for CAR T-cell-related thrombocytopenia in relapsed/refractory multiple myeloma.

BACKGROUND: Patients with multiple myeloma (MM) treated with anti-B cell maturation antigen (BCMA) and chimeric antigen receptor (CAR) T-cell therapy tend to show delayed platelet recovery. PATIENTS AND METHODS: This single-center retrospective observational study included a cohort of patients with MM treated with anti-BCMA CAR-T cells in ChiCTR-OPC-16009113, ChiCTR1800018137, and ChiCTR1900021153. RESULTS: Fifty-eight patients with MM treated with anti-BCMA CAR-T cells were included. Delayed platelet recovery (platelet count not recovering to 50 × 109/L within 28 days) was observed in 36 % of patients. Regression analysis identified several factors that influenced platelet recovery, and accordingly, a Recovery-Model was developed. A high Recovery-Model score indicates a greater risk of delayed platelet recovery after CAR-T cell infusion and reflects the risk of hematologic toxicity. The model's predictive biomarkers included baseline platelet count, baseline hemoglobin level, logarithm of baseline Ferritin level, and cytokine release syndrome grade. Finally, survival analysis showed a significant relationship between overall survival, delayed platelet recovery (p = 0.0457), and a high Recovery-Model score (p = 0.0011). CONCLUSIONS: Inflammation-related factors and bone marrow reserves are associated with delayed platelet recovery. Therefore, we developed a model to predict the risk of delayed platelet recovery and hematological toxicity in relapsed/refractory patients with MM after anti-BCMA CAR-T cell treatment.

Monitoring anti-CD19 chimeric antigen receptor T cell population by flow cytometry and its consistency with digital droplet polymerase chain reaction.

Anti-CD19 chimeric antigen receptor (CAR19) T cell therapy has produced impressive clinical efficacy in patients with relapsed or refractory B-cell malignancies. As a living drug, monitoring the pharmacokinetics of CAR T cells in vivo is an important part of clinical work, which provides valuable information for assessing therapeutic response and related side effects. However, no guidelines are available regarding the detection and quantification of CAR T cells. Flow cytometry is a convenient and commonly used method in monitoring CAR T cell kinetics, but its performance remains to be validated. By using a commercial anti-idiotype antibody that detects unique epitopes on the most popular CAR19 construct, we evaluated important performance parameters, including specificity, lower limit of detection, lower limit of quantification, and precision of flow cytometry in the detection and quantification of CAR19 T cells. Consistency between the results generated by flow cytometry and droplet digital PCR was then investigated in 188 pairs of clinical data and in cell line experiments. Rabbit anti-mouse FMC63 monoclonal antibody possesses high specificity in the detection of CAR19 positive cells by FCM with a cut-off value of 0.05%. The results produced by flow cytometry and ddPCR were well correlated in the clinical samples and in cell lines, but the correlation deteriorated as the abundance of CAR19 positive cells decreased. This was especially evident with less than 0.5% of lymphocytes in clinical data, possibly due to reduced precision (indicated by intra- and inter-assay coefficients of variability) of both droplet digital PCR and flow cytometry. We demonstrated that flow cytometry using anti-idiotype antibody is a reliable and robust approach in the detection and quantification of CAR19 T cells in vivo and has good consistency with droplet digital PCR in monitoring CAR19 T cell kinetics.

A Model Perspective Explanation of the Long-Term Sustainability of a Fully Human BCMA-Targeting CAR (CT103A) T-Cell Immunotherapy.

Different from canonical drugs, CAR T-cells are "living drugs", which derived from patient's own blood. Studies of the pharmacokinetics of CAR T-cells could improve our understanding of their efficacy, safety, optimal dosage, and other characterizes. We previously reported a phase I study of a novel fully human BCMA-targeting CAR (CT103A) in 18 patients with relapsed/refractory multiple myeloma. CT103A exhibited extraordinary persistence with low anti-drug antibody positivity. To figure out the pharmacokinetic characterizes and investigate the potential reason of CT103A's long-term persistence, we established a population pharmacokinetic (PopPK) model of CT103A based on 18 patients cohort by applying nonlinear mixed-effects modeling and analyzed the CAR T-cell clonal evolution. The results suggested that extramedullary spreading was found to impair Cmax and was therefore added as a covariate to the modified model. The model revealed tocilizumab and corticosteroids showed no impact on the CT103A expansion rate. No dominant clone existed in patients with persistently high peripheral CT103A by CAR integration sites analysis. Finally, patients with lower contraction rate constants and higher Cmax as well as memory CT103A fraction could achieve better clinical responses. Taken together, this study developed a PopPK model of a fully human anti-BCMA CAR T-cell therapy, and summarized its model characteristics. We suggested that the long-term persistence of CT103A was attributed to the memory CAR T-cell fraction but not the clonal evolution. This study will improve people's understanding of pharmacokinetics and PopPK of CAR T-cell immunotherapy.

Longitudinal Monitoring of Plasma Circulating Tumour DNA Enables the Prediction of Early Relapse in Patients with Non-Hodgkin Lymphoma: A Case Series.

Growing evidence now suggests that circulating tumour DNA (ctDNA) has great potential as a non-invasive biomarker for disease monitoring, since ctDNA carries tumour-specific modifications. In particular, monitoring ctDNA has important implications for identifying patients with haematological malignancies at clinical risk of disease progression. We hereby describe three patients with B-cell non-Hodgkin lymphoma and investigate the clinical value of sequential ctDNA profiling for the early detection of tumour relapse. Somatic mutations in diagnostic tumour biopsy samples of these three patients were identified by applying high-throughput next-generation sequencing. Droplet digital PCR probes and primers were designed and tested for each hotspot mutation. Serial ctDNA analysis was subsequently conducted among these three patients. We found that the longitudinal monitoring of plasma ctDNA could predict for at least one month in advance compared with flow cytometry, cytology and conventional imaging modalities. Therefore, our results support liquid biopsy based on ctDNA as a non-invasive complementary modality to other detection methods for detecting early relapse and contribute to more precise management for non-Hodgkin lymphoma patients.

Inherited Genetic Susceptibility to Nonimmunosuppressed Epstein-Barr Virus-associated T/NK-cell Lymphoproliferative Diseases in Chinese Patients.

Epstein-Barr virus (EBV) T/NK-cell lymphoproliferative diseases are characterized by clonal expansion of EBV-infected T or NK cells, including chronic active EBV infection of T/NK-cell type (CAEBV+T/NK), EBV-associated hemophagocytic lymphohistiocytosis (EBV+HLH), extranodal NK/T-cell lymphoma of nasal type (ENKTL), and aggressive NK-cell leukemia (ANKL). However, the role of inherited genetic variants to EBV+T/NK-LPDs susceptibility is still unknown. A total of 171 nonimmunosuppressed patients with EBV+T/NK-LPDs and 104 healthy donors were retrospectively collected and a targeted sequencing study covering 15 genes associated with lymphocyte cytotoxicity was performed. The 94 gene variants, mostly located in UNC13D, LYST, ITK, and PRF1 genes were detected, and mutations covered 28/50 (56.00%) of CAEBV-T/NK, 31/51 (60.78%) of EBV+HLH, 13/28 (46.42%) of ENKTL, and 13/48 (27.09%) of ANKL. Most mutations represented monoallelic and missense. Three-year overall survival rate of patients with CAEBV-T/NK and EBV+HLH was significantly lower in patients with germline mutations than in those without germline mutations (P=0.0284, P=0.0137). Our study provided novel insights into understanding a spectrum of nonimmunosuppressed EBV+T/NK-LPDs with respect to genetic defects associated with lymphocyte cytotoxicity and reminded us that the gene sequencing may be an auxiliary test for diagnosis and risk stratification of EBV+T/NK-LPDs.

TP53-Mutated Circulating Tumor DNA for Disease Monitoring in Lymphoma Patients after CAR T Cell Therapy.

Chimeric antigen receptor T (CAR T) cell immunotherapy has shown remarkable efficacy in non-Hodgkin's lymphoma (NHL) patients. Minimal residual disease (MRD) monitoring in NHL is essential after CAR T cell therapy, which can be achieved by monitoring circulating tumor DNA (ctDNA). The mutation of TP53 in NHL has been suggested to be associated with a poor prognosis. However, whether TP53-mutated ctDNA can be used as a biomarker remains undetermined. In this study, a total of 40 patients with mutated TP53 who received CAR T cell treatment were analyzed, and specific probes targeting 29 different TP53 mutation sites in the 40 patients were designed and verified. Then, the presence of TP53-mutated ctDNA in longitudinal plasma samples was tracked by droplet digital PCR. Patients were stratified into two groups, favorable or unfavorable, based on their highest ctDNA level using a MAF cutoff of 3.15% according to the ROC curve. The unfavorable group had significantly worse PFS than the favorable group (p < 0.001). Our results suggest that patients with mutated TP53 with a favorable ctDNA profile in the first trimester have better prognostic outcomes than patients with an unfavorable profile, and ctDNA can be a reliable predictor of the subsequent clinical outcome.

Dynamics of Blood Viral Load Is Strongly Associated with Clinical Outcomes in Coronavirus Disease 2019 (COVID-19) Patients: A Prospective Cohort Study.

The prevalence and clinical relevance of viremia in patients with coronavirus disease 2019 (COVID-19) have not been well studied. A prospective cohort study was designed to investigate blood viral load and clearance kinetics in 52 patients (median age, 62 years; 31 [59.6%] male) and explore their association with clinical features and outcomes based on a novel one-step RT droplet digital PCR (RT-ddPCR). By using one-step RT-ddPCR, 92.3% (48 of 52) of this cohort was quantitatively detected with viremia. The concordance between the blood and oropharyngeal swab tests was 60.92% (53 of 87). One-step RT-ddPCR was tested with a 3.03% false-positive rate and lower 50% confidence interval of detection at 54.026 copies/mL plasma. There was no reduction in the blood viral load in all critical patients, whereas the general and severe patients exhibited a similar ability to clear the viral load. The viral loads in critical patients were significantly higher than those in their general and severe counterparts. Among the 52 study patients, 30 (58%) were discharged from the hospital. Among half of the 30 discharged patients, blood viral load remained positive, of which 76.9% (10 of 13) completely cleared their blood viral load at follow-up. Meanwhile, none of their close contacts had evidence of infection. Quantitative determination of the blood viral test is of great clinical significance in the management of patients with coronavirus disease 2019.

CAR T-Cell Therapy Is Effective but Not Long-Lasting in B-Cell Lymphoma of the Brain.

Advanced central nervous system (CNS) lymphoma is an exclusion criterion for most chimeric antigen receptor (CAR) T-cell studies due to the associated levels of neurotoxicity. In this study, we described five patients with chemorefractory B-cell CNS lymphoma who received CAR19 and CAR22 T-cell "Cocktail" therapy and follow-up for 6-16 months. All patients experienced cytokine release syndrome (CRS). Two patients experienced CAR T-cell-related encephalopathy syndrome (CRES), which was controllable. The best response was observed in two patients, who successfully achieved complete remissions (CR), and the other three patients achieved partial remissions (PR). Four patients had progressive disease (PD) after remission. In addition, one CR patient and one PD patient accepted CAR T-cell infusion following hematopoietic stem cell transplantation therapy in the 3rd month and were in ongoing remission for 14 and 6 months of follow-up, respectively. The targeted antigens in two patients were still positive, and CAR T-cells were reboosted in the cerebrospinal fluid (CSF) after PD, but a small number of CD3-positive T-cells were observed to infiltrate into the tumor. Our study indicates the efficacy of CAR T-cell therapy for CNS lymphoma with an acceptable safety profile; however, the remission did not last long, perhaps due to the tumor immunosuppressive microenvironment (TME) of the CNS. CAR T-cell therapy should be combined with other treatments to help improve the TME of cerebral lymphoma.

Detection and Quantification of Chimeric Antigen Receptor Transgene Copy Number by Droplet Digital PCR versus Real-Time PCR.

Chimeric antigen receptor (CAR) T-cell immunotherapy is a new strategy for the treatment of refractory B-cell malignancies; therefore, the rapid and accurate quantification of CAR transgene copy number is essential. Real-time PCR was used for quantifying the copy number of chimeric antigen receptor transgene. Droplet digital PCR (ddPCR) is an absolute quantification method that does not require a standard curve. In this study, key performance parameters of the ddPCR and real-time PCR methods were assessed, including linearity, detection range, the lower limit of detection, repeatability, reproducibility, and accuracy, using a series of gradient diluted standards and clinical peripheral blood samples from CAR T-cell patients. The two platforms showed a good correlation for the standards (Pearson R2 = 0.9966; P < 0.0001) and clinical samples (Pearson R2 = 0.8952; P < 0.0001), and both showed good linearity (R2 = 0.9996 for ddPCR; R2 = 0.9984 for real-time PCR) over the detection range. Compared with real-time PCR, ddPCR showed lower intra-assay and interassay CVs for the series of diluted standards, which indicated ddPCR has better repeatability and reproducibility. The limit of detection of ddPCR was lower compared with that of real-time PCR. The combined results suggest that ddPCR is a more promising tool for the detection and quantification of the chimeric antigen receptor transgene copy number.

CAR T-cell therapy for a relapsed/refractory acute B-cell lymphoblastic lymphoma patient in the context of Li-Fraumeni syndrome.

BACKGROUND: Li-Fraumeni syndrome (LFS) is characterized as an autosomal dominant cancer predisposition disorder caused by germline TP53 gene mutations. Both primary and therapy-related hematopoietic malignancies with LFS are associated with dismal outcomes with standard therapies and even allogenic stem cell transplantation (SCT). CASE PRESENTATION: We reported a relapsed/refractory acute B-cell lymphoblastic lymphoma (B-LBL) patient in the context of LFS. He was identified to harbor a TP53 c.818G>A (p.R273H) germline mutation, and his family history was significant for rectal carcinoma in his father, an unknown cancer in his sister and acute lymphoblastic leukemia in his brother and one of his sons. The patient received murine monoclonal anti-CD19 and anti-CD22 chimeric antigen receptor (CAR) T-cell "cocktail" therapy and achieved complete remission with negative minimal residual disease (MRD), as assessed by morphology and multiparameter flow cytometry. Fifteen months after murine monoclonal CAR T-cell "cocktail" therapy, the patient's B-LBL recurred. Fortunately, a round of fully human monoclonal anti-CD22 CAR T-cell therapy was still effective in this patient, and he achieved CR again and continued to be followed. Each time after infusion, the CAR T-cells underwent extremely rapid exponential expansion, which may be due to the disruption of TP53, a gene that can functionally control cell cycle arrest. Grade 4 and grade 1 cytokine release syndrome occurred after the first and second rounds of CAR T-cell therapy, respectively. CONCLUSIONS: This case provides the first report of the use of CAR T-cell therapy in a hematologic malignancy patient with LFS. As traditional chemotherapy and allogenic SCT are not effective therapy strategies for patients with hematologic malignancies and LFS, CAR T-cell therapy may be an alternate choice.ChiCTR-OPN-16008526 and ChiCTR1900023922.