An optimized immunomagnetic bead-based negative selection protocol for CD4 T-cell isolation from mouse lymph nodes and spleen

Herpesvirus entry mediator regulates the transduction of Tregs via STAT5/Foxp3 signaling pathway in ovarian cancer cells

The ratio of regulatory T cells (Treg) in peripheral blood of cancer patients has a closely correlation to the occurrence and development of ovarian cancer. In this study, our aim to explore the expression of herpesvirus entry mediator (HVEM) in ovarian cancer and its correlation with Tregs. The expression of HVEM in peripheral blood of ovarian cancer patients was detected by ELISA, and the ratio of CD4+ CD25 + Foxp3 positive Tregs cells was detected by flow cytometry. Ovarian cancer cell lines with high- and low-HVEM expression were constructed. CD4+ cells were co-cultured with ovarian cancer (OC) cells, and the expressions of IL-2 and TGF-β1 in the supernatant of cells were detected by ELISA, and western blot was used to detect the expressions of STAT5, p-STAT5, and Foxp3. The results indicated that the number of Treg cells in the peripheral blood of OC patients increased, and the expression of HVEM increased, the two have a certain correlation. At the same time, the overexpression of HVEM promoted the expression of cytokines IL-2 and TGF- β1, promoted the activation of STAT5 and the expression of Foxp3, leading to an increase in the positive rate of Treg, while the HVEM gene silence group was just the opposite. Our results showed that the expression of HVEM in OC cells has a positive regulation effect on Tregs through the STAT5/Foxp3 signaling pathway. To provide experimental basis and related mechanism for the clinical treatment of ovarian cancer.

Mouse splenocyte enrichment strategies via negative selection for broadened single-cell transcriptomics

Mammalian splenic tissue is rich in functional immune cells, primarily lymphocytes which can mask low-abundance populations in downstream analyses. This protocol enriches minority immune cell populations from mouse spleen via immunomagnetic negative depletion to generate an untouched enriched cell fraction. Enriched cells are then spiked with untouched splenocytes in a controlled repopulation, validated by flow cytometry and results in a single-cell transcriptomic clustering analysis with a broadened cellular landscape.

Co-culture Systems of Drug-Treated Acute Myeloid Leukemia Cells and T Cells for In Vitro and In Vivo Study

A combination of immunotherapy and chemotherapy strategies could strengthen antitumor effects. This protocol elucidates a robust method via co-culturing drug pre-treated acute myeloid leukemia cells with CD3⁺ T cells, derived from leukoreduction system chambers, for in vitro and in vivo study. We optimized several aspects of the procedures, including timing of drug treatment, quantification of tumor cells, and approach of combination of CD3⁺ T cells with drug treatment in vivo. This enables the readouts of the interplay between drugs and T cells.

For complete details on the use and execution of this protocol, please refer to Su et al. (2020).

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Generate CD3⁺ T cells from leukoreduction system chambers using magnetic separation

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Co-culture T cells with drug-pretreated fluorescently labeled tumor cells

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Determine T cell toxicity in the co-culture system via absolute counting beads

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Combine T cells and drug treatment in the xenograft mouse with luciferase-labeled AML cells

Role of the EHD Family of Endocytic Recycling Regulators for TCR Recycling and T Cell Function

T cells use the endocytic pathway for key cell biological functions, including receptor turnover and maintenance of the immunological synapse. Some of the established players include the Rab GTPases, the SNARE complex proteins, and others, which function together with EPS-15 homology domain-containing (EHD) proteins in non-T cell systems. To date, the role of the EHD protein family in T cell function remains unexplored. We generated conditional EHD1/3/4 knockout mice using CD4-Cre and crossed these with mice bearing a myelin oligodendrocyte glycoprotein-specific TCR transgene. We found that CD4⁺ T cells from these mice exhibited reduced Ag-driven proliferation and IL-2 secretion in vitro. In vivo, these mice exhibited reduced severity of experimental autoimmune encephalomyelitis. Further analyses showed that recycling of the TCR-CD3 complex was impaired, leading to increased lysosomal targeting and reduced surface levels on CD4⁺ T cells of EHD1/3/4 knockout mice. Our studies reveal a novel role of the EHD family of endocytic recycling regulatory proteins in TCR-mediated T cell functions.

Purification of Mouse Bone Marrow-Derived Stem Cells Promotes Ex Vivo Neuronal Differentiation

The main objective of this study is to test the potential of specific populations of mouse bone marrow-derived stem cells (BMSCs) to differentiate into the neuronal cell lineage. Bone marrow of 33 mice was aspirated under general anesthesia. The collected marrows were analyzed for cell counts, compositions, and percentages of different stem cell types. We used the Midi MACS magnetic separator to purify specific populations of stem cells from the aspirated bone marrow. Cells were analyzed using flow cytometry. We assessed the presence of stem cell antigen-1 (Sca-1+) and prominin-1+ cells in the cellular fraction that was depleted of lineage-committed cells (lineage-). Both purified and nonpurified cells were cultured ex vivo using specific growth media with factors that drive the cells to differentiate into the neuroglial cell types. Cells were then analyzed by flow cytometry for expression of specific neuronal markers. Our results showed that there was an increase of Sca-1+ and prominin-1+ cells in the lineage- fraction over the unpurified BM. After lineage depletion, the percentages of Sca-1+ and prominin-1+ cells increased from 4.9% and 2.6%, up to 76.1% and 59%, respectively. Unpurified mouse BM differentiated into fibroblasts, whereas Sca-1+ cells were able to generate astrocytes. Interestingly, purified prominin-1+ cells were able to generate neuronal cells. Purification of adult bone marrow-derived stem cells enhances their potentiality for differentiating into specific neuronal cell lineages.