Browse
Submit Data
Databases
API
Help

Dataset Information

25 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Siglec-6 is a target for chimeric antigen receptor T-cell treatment of chronic lymphocytic leukemia.

ABSTRACT: The only current curative treatment for chronic lymphocytic leukemia (CLL) is allogenic hematopoietic stem cell transplantation. Chimeric antigen receptor treatment targeting CD19 for CLL achieved some complete responses, suggesting the need for alternative or combinational therapies to achieve a more robust response. In this work, we evaluated CAR-T cells specific for Siglec-6, an antigen expressed in CLL, as a novel CAR-T cell treatment for CLL. We found that detection of SIGLEC6 mRNA and Siglec-6 protein is highly restricted to placenta and immune cells in other tissues and it is not expressed in hematopoietic stem cells. We generated CAR-T cells specific for Siglec-6 based on the sequence of the fully human anti-Siglec-6 antibody (JML1), which was identified in a CLL patient that was cured after allo-hematopoietic stem cell transplantation (alloHSCT), and observed that it specifically targeted CLL cells in vitro and in a xenograft mouse model. Interestingly, a short hinge region increased the activity of CAR-T cells to target cells expressing higher Siglec-6 levels but similarly targeted CLL cells expressing lower Siglec-6 levels in vitro and in vivo. Our results identify a novel CAR-T cell therapy for CLL and establish Siglec-6 as a possible target for immunotherapy.

SUBMITTER: Kovalovsky D

PROVIDER: S-EPMC8384967 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Chimeric antigen receptor-modified T cell therapy in chronic lymphocytic leukemia.

Project description:Chronic lymphocytic leukemia (CLL), a common type of B cell chronic lymphoproliferative disorder in adults, has witnessed enormous development in its treatment in recent years. New drugs such as ibrutinib, idelalisib, and venetoclax have achieved great success in treating relapsed and refractory (R/R) CLL. In addition, with the development of immunotherapy, chimeric antigen receptor-engineered T cells (CAR-T) therapy, a novel adoptive immune treatment, has also become more and more important in treating R/R CLL. It combines the advantages of T cells and B cells via ex vivo gene transfer technology and is able to bind targets recognized by specific antibodies without antigen presentation, thus breaking the restriction of major histocompatibility complex. So far, there have been lots of studies exploring the application of CAR-T therapy in CLL. In this review, we describe the structure of chimeric antigen receptor, the preclinical, and clinical results of CAR-T therapy against CLL, along with its adverse events and advances in efficacy.

| S-EPMC6247712 | biostudies-literature

Leukemic extracellular vesicles induce chimeric antigen receptor T cell dysfunction in chronic lymphocytic leukemia.

Project description:Chimeric antigen receptor (CAR) T cell therapy has yielded unprecedented outcomes in some patients with hematological malignancies; however, inhibition by the tumor microenvironment has prevented the broader success of CART cell therapy. We used chronic lymphocytic leukemia (CLL) as a model to investigate the interactions between the tumor microenvironment and CART cells. CLL is characterized by an immunosuppressive microenvironment, an abundance of systemic extracellular vesicles (EVs), and a relatively lower durable response rate to CART cell therapy. In this study, we characterized plasma EVs from untreated CLL patients and identified their leukemic cell origin. CLL-derived EVs were able to induce a state of CART cell dysfunction characterized by phenotypical, functional, and transcriptional changes of exhaustion. We demonstrate that, specifically, PD-L1+ CLL-derived EVs induce CART cell exhaustion. In conclusion, we identify an important mechanism of CART cell exhaustion induced by EVs from CLL patients.

| S-EPMC8058445 | biostudies-literature

Chimeric antigen receptor therapy for chronic lymphocytic leukemia: what are the challenges?

Project description:Chimeric antigen receptor (CAR)-modified T cells targeting CD19 expressed by normal and malignant B cells is a unique therapy for patients with chronic lymphocytic leukemia (CLL); recent results highlight the potential of this therapy for patients with relapsed CLL. Because adoptive transfer of CAR-modified T cells is a novel approach, there are issues for the medical oncologist to consider when evaluating current and future clinical trials for CLL patients. This article reviews the impact of CAR design, T-cell production, T-cell dose, conditioning regimens, and tumor burden at the time of CAR-modified T-cell infusion on the efficacy of this therapy.

| S-EPMC3615434 | biostudies-literature

The inhibitory receptor Siglec-G controls the severity of chronic lymphocytic leukemia

Project description:Chronic Lymphocytic Leukaemia (CLL) is the most common leukemia in adults in the Western world. B cell receptor (BCR) signalling is known to be crucial for the pathogenesis and maintenance of CLL cells which develop from mature CD5+ B cells. BCR signalling is regulated by the inhibitory co-receptor Siglec-G and Siglec-G-deficient mice have an enlarged CD5+ B1a cell population. Here, we determine how Siglec-G expression influences the severity of CLL. Our results show that Siglec-G deficiency leads to earlier onset and more severe course of the CLL-like disease in the murine Eµ-TCL1 model. In contrast, mice overexpressing Siglec-G on the B cell surface are almost completely protected from developing CLL-like disease. Furthermore, we observe a downmodulation of the human orthologue Siglec-10 from the surface of human CLL cells. These results demonstrate a critical role for Siglec-G in disease progression in mice, and suggest that a similar mechanism for Siglec-10 in human CLL may exist.

| S-SCDT-10_15252-EMBR_202256420 | biostudies-other

Determinants of response and resistance to CD19 chimeric antigen receptor (CAR) T cell therapy of chronic lymphocytic leukemia.

Project description:Tolerance to self-antigens prevents the elimination of cancer by the immune system1,2. We used synthetic chimeric antigen receptors (CARs) to overcome immunological tolerance and mediate tumor rejection in patients with chronic lymphocytic leukemia (CLL). Remission was induced in a subset of subjects, but most did not respond. Comprehensive assessment of patient-derived CAR T cells to identify mechanisms of therapeutic success and failure has not been explored. We performed genomic, phenotypic and functional evaluations to identify determinants of response. Transcriptomic profiling revealed that CAR T cells from complete-responding patients with CLL were enriched in memory-related genes, including IL-6/STAT3 signatures, whereas T cells from nonresponders upregulated programs involved in effector differentiation, glycolysis, exhaustion and apoptosis. Sustained remission was associated with an elevated frequency of CD27+CD45RO-CD8+ T cells before CAR T cell generation, and these lymphocytes possessed memory-like characteristics. Highly functional CAR T cells from patients produced STAT3-related cytokines, and serum IL-6 correlated with CAR T cell expansion. IL-6/STAT3 blockade diminished CAR T cell proliferation. Furthermore, a mechanistically relevant population of CD27+PD-1-CD8+ CAR T cells expressing high levels of the IL-6 receptor predicts therapeutic response and is responsible for tumor control. These findings uncover new features of CAR T cell biology and underscore the potential of using pretreatment biomarkers of response to advance immunotherapies.

| S-EPMC6117613 | biostudies-literature

Chimeric antigen receptor T cells persist and induce sustained remissions in relapsed refractory chronic lymphocytic leukemia.

Project description:Patients with multiply relapsed or refractory chronic lymphocytic leukemia (CLL) have a poor prognosis. Chimeric antigen receptor (CAR)-modified T cells targeting CD19 have the potential to improve on the low complete response rates with conventional therapies by inducing sustained remissions in patients with refractory B cell malignancies. We previously reported preliminary results on three patients with refractory CLL. We report the mature results from our initial trial using CAR-modified T cells to treat 14 patients with relapsed and refractory CLL. Autologous T cells transduced with a CD19-directed CAR (CTL019) lentiviral vector were infused into patients with relapsed/refractory CLL at doses of 0.14 × 10(8) to 11 × 10(8) CTL019 cells (median, 1.6 × 10(8) cells). Patients were monitored for toxicity, response, expansion, and persistence of circulating CTL019 T cells. The overall response rate in these heavily pretreated CLL patients was 8 of 14 (57%), with 4 complete remissions (CR) and 4 partial remissions (PR). The in vivo expansion of the CAR T cells correlated with clinical responses, and the CAR T cells persisted and remained functional beyond 4 years in the first two patients achieving CR. No patient in CR has relapsed. All responding patients developed B cell aplasia and experienced cytokine release syndrome, coincident with T cell proliferation. Minimal residual disease was not detectable in patients who achieved CR, suggesting that disease eradication may be possible in some patients with advanced CLL.

| S-EPMC5909068 | biostudies-literature

Calreticulin as a novel B-cell receptor antigen in chronic lymphocytic leukemia.

Project description: Not available

| S-EPMC5622869 | biostudies-literature

BET bromodomain protein inhibition reverses chimeric antigen receptor extinction and reinvigorates exhausted T cells in chronic lymphocytic leukemia.

Project description:Chimeric antigen receptor (CAR) T cells have induced remarkable antitumor responses in B cell malignancies. Some patients do not respond because of T cell deficiencies that hamper the expansion, persistence, and effector function of these cells. We used longitudinal immune profiling to identify phenotypic and pharmacodynamic changes in CD19-directed CAR T cells in patients with chronic lymphocytic leukemia (CLL). CAR expression maintenance was also investigated because this can affect response durability. CAR T cell failure was accompanied by preexisting T cell-intrinsic defects or dysfunction acquired after infusion. In a small subset of patients, CAR silencing was observed coincident with leukemia relapse. Using a small molecule inhibitor, we demonstrated that the bromodomain and extra-terminal (BET) family of chromatin adapters plays a role in downregulating CAR expression. BET protein blockade also ameliorated CAR T cell exhaustion as manifested by inhibitory receptor reduction, enhanced metabolic fitness, increased proliferative capacity, and enriched transcriptomic signatures of T cell reinvigoration. BET inhibition decreased levels of the TET2 methylcytosine dioxygenase, and forced expression of the TET2 catalytic domain eliminated the potency-enhancing effects of BET protein targeting in CAR T cells, providing a mechanism linking BET proteins and T cell dysfunction. Thus, modulating BET epigenetic readers may improve the efficacy of cell-based immunotherapies.

| S-EPMC8363276 | biostudies-literature

Chimeric antigen receptor-modified T cells in chronic lymphoid leukemia.

Project description:We designed a lentiviral vector expressing a chimeric antigen receptor with specificity for the B-cell antigen CD19, coupled with CD137 (a costimulatory receptor in T cells [4-1BB]) and CD3-zeta (a signal-transduction component of the T-cell antigen receptor) signaling domains. A low dose (approximately 1.5×10(5) cells per kilogram of body weight) of autologous chimeric antigen receptor-modified T cells reinfused into a patient with refractory chronic lymphocytic leukemia (CLL) expanded to a level that was more than 1000 times as high as the initial engraftment level in vivo, with delayed development of the tumor lysis syndrome and with complete remission. Apart from the tumor lysis syndrome, the only other grade 3/4 toxic effect related to chimeric antigen receptor T cells was lymphopenia. Engineered cells persisted at high levels for 6 months in the blood and bone marrow and continued to express the chimeric antigen receptor. A specific immune response was detected in the bone marrow, accompanied by loss of normal B cells and leukemia cells that express CD19. Remission was ongoing 10 months after treatment. Hypogammaglobulinemia was an expected chronic toxic effect.

| S-EPMC3387277 | biostudies-literature

CD19 Chimeric Antigen Receptor T Cells From Patients With Chronic Lymphocytic Leukemia Display an Elevated IFN-γ Production Profile.

Project description:CD19 chimeric antigen receptor (CAR) T cell immunotherapy has demonstrated dramatic results for the treatment of B cell malignancies such as chronic lymphocytic leukemia (CLL). As T cell defects are common in patients with CLL, we compared the T cells from these patients with healthy donors (HDs), and subsequently the CD19 CAR T cells produced from patients and HDs. Despite initial differences when comparing the phenotype of circulating T cells in patients with CLL and HDs, the CD19 CAR T cells manufactured from patients' or HDs' cells showed a similar phenotype (effector memory or terminally differentiated), both were specifically activated by and killed CD19 target cells, and secreted cytokines (ie, IL-2, TNF, and IFN-γ). The frequency of CD19 CAR T cells producing IFN-γ was significantly higher in cells produced from patients as compared with those produced from HDs. Furthermore, our data showed that the polyfunctional profile of CD19 CAR T cells was differently modulated by CD19 K562 cells and autologous B cells. The increased IFN-γ production by CD19 CAR T cells produced from patients with CLL after in vitro stimulation, may if this is also the case in vivo, contribute to a higher risk of a cytokine release syndrome in patients. The different impact by CD19 target cells on the polyfunctional profile of CD19 CAR T cells in vitro underlines the importance of the choice of CD19 target cells when assessing CD19 CAR T cells functions.

| S-EPMC8057115 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data