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Integrins, Integrin Regulators, and the Extracellular Matrix
Published in Bruce S. Bochner, Adhesion Molecules in Allergic Disease, 2020
Stephen W. Hunt, Sirid-Aimée Kellermann, Yoji Shimizu
Analysis of inside-out signaling in several cultured human cell lines has also revealed currently undefined defects in this signaling event. Although the Jurkat T cell line expresses high levels of the LFA-1 integrin, adhesion assays reveal no adhesion of Jurkat cells to ICAM-1 (89,90). Furthermore, PMA stimulation is incapable of increasing LFA-1 activity, even though PMA stimulation up-regulates the functional activity of β1 integrins on the same cell (89). However, divalentcation conditions that increase the affinity of LFA-1 are capable of increasing LFA-1-mediated adhesion of Jurkat cells to ICAM-1 (89). This suggests that there is not a structural defect in the LFA-1 integrin that prevents it from mediating adhesion. The ability of PMA to selectively up-regulate β1 integrin activity on Jurkat cells also implies some heterogeneity in inside-out signaling to β1 versus β2 integrins. The nature of the defect in LFA-1 function in Jurkat cells remains undefined, although there are similar defects in LFA-1 activity in other T-cell lines as well (89).
Involvement of Dopamine with Various Cancers
Published in Nira Ben-Jonathan, Dopamine, 2020
T-cell lymphomas account for ~15% of all NHLs. There are many forms of T-cell lymphomas, which can be aggressive or indolent [14]. Jurkat cells are an immortalized human T-lymphocyte cell line that was originally obtained from the peripheral blood of a boy with T cell leukemia. They are commonly used to study T-cell signaling, apoptosis, and expression of chemokine receptors susceptible to vial entry, particularly HIV. Jurkat lymphocytes express many components of the DA system: DAT and vesicular monoamine transporter (VMAT), D1-like and D2-like receptors, confirming their ability to internalize, store and respond to DA. Yet, they lack TH expression and do not synthesize DA de novo [15]. To examine the effects of DA on HIV-1 gene transcription, a reporter containing the full length long terminal repeat of HIV-1 was transfected into Jurkat cells [16]. Large doses of DA (50–200 μM) stimulated HIV-1 transcription via nuclear factor kappa B (NF-κB) activation. The combination of DA and tumor necrosis factor alpha (TNF-α) increased HIV-1 transcription as well as replication. Others reported that D1R activation inhibited cell proliferation in T-cells from normal volunteers but failed to do so in Jurkat cells because of overexpression of phosphodiesterase (PDE) activity [17].
Biocatalytic Nanoreactors for Medical Purposes
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
Oscar González-Davis, Chauhan Kanchan, Rafael Vazquez-Duhalt
Zelphati et al. (2001) developed a lipid-mediated delivery system composed of trifluoroacetylated lipopolyamine (TFA-DODAPL) and dioleoyl phosphatidylethanolamine (DOPE) able of successfully delivering β-galactosidase (β-Gal) and caspase 3 (CP3), caspase 8 (CP8), and granzyme B into cultured cell lines as demonstrated by intracellular fluorescence intensity measurements. In order to prove the functionality of their delivery system, the authors tested the ability of TFA-DODAPL:DOPE to deliver functional granzyme B into primary human AML cells by using a fluorogenic cell permeable substrate, CaspaTag, and measured the activation of endogenous caspases by flow cytometry. Similarly, CP3, CP8 and granzyme B activity was evaluated in Jurkat cells. Granzyme B and CP3 induced apoptosis in ~60% of Ki-Ras 267β1 cells.
Exploring the pharmacological mechanisms of Shuanghuanglian against T-cell acute lymphoblastic leukaemia through network pharmacology combined with molecular docking and experimental validation
Published in Pharmaceutical Biology, 2023
You Yang, Yan Yang, Yunfu Shen, Jing Liu, Yan Zeng, Chengming Wei, Chunyan Liu, Yansha Pan, Qulian Guo, Fangfang Zhong, Ling Guo, Wenjun Liu
To confirm this hypothesis, flow cytometry was used to detect the apoptosis of T-ALL cells (Jurkat and Molt4). After treatment with different concentrations of SHL (0, 0.1, 0.2, 0.4 mg/mL) for 24 h, Jurkat and Molt4 cells were collected. The results showed that the apoptosis rate in both cell lines increased in a dose-dependent manner (Figure 3(A,B)). The apoptosis rate increased from 6.92 ± 2.00% to 61.01 ± 1.39% for Jurkat cells and 8.39 ± 1.31% to 44.91 ± 1.75% for Molt4 cells (Figure 3(A,B)). Moreover, morphological apoptosis was evaluated to reconfirm the apoptosis of Jurkat cells. As shown in Figure 3(C), an increase in the number of apoptotic cells was observed with increasing SHL concentration under fluorescence microscopy. Finally, the expression of proteins related to apoptosis was measured by Western blotting. The results showed that the level of an apoptosis executor protein, cleaved caspase7 increased in a dose-dependent manner in Jurkat cells. The cleaved PARP (cleaved poly ADP-ribose polymerase) protein level also increased with increasing SHL concentration (Figure 3(D–F)). These results showed that SHL induced apoptosis in T-ALL.
Synapse topology and downmodulation events determine the functional outcome of anti-CD19 T cell-redirecting strategies
Published in OncoImmunology, 2022
Ángel Ramírez-Fernández, Óscar Aguilar-Sopeña, Laura Díez-Alonso, Alejandro Segura-Tudela, Carmen Domínguez-Alonso, Pedro Roda-Navarro, Luis Álvarez-Vallina, Belén Blanco
We have recently reported the generation of STAb-T19 cells secreting a previously uncharacterized anti-CD19 × anti-CD3 BiTE and demonstrated their potent antitumor activity in relevant in vivo B-ALL models when compared to CAR-T cells expressing a cell surface CD19-targeted second-generation CAR.28 Interestingly, we observed significant differences in the topology of 19-CAR- and 19-BiTE-mediated synapses in human primary T lymphocytes. In the present study, we have performed a detailed analysis on the characteristics and potential outcomes of both types of anti-CD19-mediated target cell-T cell interactions. For this purpose, we have used the Jurkat human T cell line, which has been widely used to study T cell activation, signaling, and IS assembly.36 Contrary to primary T cells, Jurkat cells can be easily expanded and long-term cultured after transduction without losing CAR expression or BiTE secretion, avoiding transduction-to-transduction differences and loss of transgene expression. In addition, clonal stimulation by superantigens provides a proper control that mimics the canonical IS and, together with the high transduction efficiency achieved in Jurkat cells, allows to perform experiments with a high number of T cell-target cell interactions. Jurkat cell stimulation with SEE and B-cell lines has been previously used for synapse studies, 37 and Jurkat cells have been employed to evaluate the CAR- and BsAb-induced IS and signaling in T cells.31,38
Jurkat T Cells are Immunophenotypically Distinct from T-Cell Acute Lymphoblastic Leukemia Cells Due to High-Level Surface Expression of CD5
Published in Cancer Investigation, 2022
Kulwant Singh, Smita Kumari, Bharat Singh, Ranjeet Bahadur Choubey, Dipendra Kumar Mitra, Ambak Kumar Rai
The Jurkat cells (E6.1) were routinely cultured in RPMI 1640 medium (Cat. No. −31800-022, Gibco Life Technologies, USA), supplemented with L-glutamine, 10% fetal bovine serum (Cat. No. − 10270106, Gibco Life Technologies, USA), and antibiotic cocktail (penicillin and streptomycin, Cat. No. – E485, Amresco Inc. USA and gentamycin Cat. No. G1397-10ml, Sigma Aldrich, USA) in a humidified chamber containing 5% CO2 at 37 °C. The cell number was maintained about 2 × 106 by subculturing. The E6.1 clone of Jurkat cells was obtained from two laboratories and characterized together to negate the inter-laboratory variations. The cultures were screened under the microscope for the presence of any contaminants as well as intermittently with flow cytometry on the forward and side scatter scales without any threshold in acquisition.