Background: Interleukin-15 (IL-15) is an important cytokine necessary for proliferation and maintenance of natural killer (NK) and CD8+ T cells, and with great promise as an immuno-oncology therapeutic. However, IL-15 has a very short half-life and a single administration does not provide the sustained exposure required for optimal stimulation of target immune cells. The purpose of this work was to develop a very long-acting prodrug that would maintain IL-15 within a narrow therapeutic window for long periods-similar to a continuous infusion.
Methods: We prepared and characterized hydrogel microspheres (MS) covalently attached to IL-15 (MS~IL-15) by a releasable linker. The pharmacokinetics and pharmacodynamics of MS~IL-15 were determined in C57BL/6J mice. The antitumor activity of MS~IL-15 as a single agent, and in combination with a suitable therapeutic antibody, was tested in a CD8+ T cell-driven bilateral transgenic adenocarcinoma mouse prostate (TRAMP)-C2 model of prostatic cancer and a NK cell-driven mouse xenograft model of human ATL (MET-1) murine model of adult T-cell leukemia.
Results: On subcutaneous administration to mice, the cytokine released from the depot maintained a long half-life of about 168 hours over the first 5 days, followed by an abrupt decrease to about ~30 hours in accordance with the development of a cytokine sink. A single injection of MS~IL-15 caused remarkably prolonged expansions of NK and ɣδ T cells for 2 weeks, and CD44hiCD8+ T cells for 4 weeks. In the NK cell-driven MET-1 murine model of adult T-cell leukemia, single-agent MS~IL-1550 μg or anti-CCR4 provided modest increases in survival, but a combination-through antibody-depedent cellular cytotoxicity (ADCC)-significantly extended survival. In a CD8+ T cell-driven bilateral TRAMP-C2 model of prostatic cancer joplink Rubisco Mouse Polyclonal Antibody, single agent subcutaneous MS~IL-15 or unilateral intratumoral agonistic anti-CD40 showed modest growth inhibition, but the combination exhibited potent, prolonged bilateral antitumor activity.
Conclusions: Our results show MS~IL-15 provides a very long-acting IL-15 with low Cmax that elicits prolonged expansion of target immune cells and high anticancer activity, especially when administered in combination with a suitable immuno-oncology agent.
Indirect signal amplification strategy with a universal probe-based lateral flow immunoassay for the rapid quantitative detection of fumonisin B1
Fumonisin B1 (FB1) is a serious threat to the health of humans and animals. Herein, a lateral flow immunoassay based on universal detection probes (goat anti-mouse IgG@Eu) that could combine with any mouse monoclonal antibody was applied to detect FB1 in corn and feed. Compared with that based on direct monoclonal antibody labeling, this assay maintained bioactivity and saved consumption of monoclonal antibodies with the indirect signal amplification effect.
The results indicated that this assay had higher sensitivity with a limit of detection (LOD) of 0.025 and 0.097 ng mL-1 (0.50 and 1.94 ng g-1 based on sample weight) in corn and feed, respectively. The detection range was about 1-50 ng mL-1 (20-1000 ng g-1 based on sample weight). In addition, the evaluation proved that it had good specificity, accuracy, precision, and applicability, and thus was suitable for the rapid and low-cost detection of fumonisin B1.
TSH-TSHR axis promotes tumor immune evasion
Background: Hormones are identified as key biological variables in tumor immunity. However, previous researches mainly focused on the immune effect of steroid hormones, while the roles that thyroid-stimulating hormone (TSH) played in the antitumor response were far from clear.
Methods: The source of TSH was determined using single-cell transcriptomic, histologic, quantitative PCR, and ELISA analysis. The influence of TSH on tumor proliferation, invasion, and immune evasion was evaluated in multiple cell lines of thyroid cancer, glioma, and breast cancer. Then transcriptomic sequencing and cellular experiments were used to identify signaling pathways. TSH receptor (TSHR) inhibitor was injected into homograft mouse tumor models with or without anti-programmed cell death protein-1 antibody.
Results: Monocyte-derived dendritic cells (moDCs) highly expressed TSHα and TSHβ2 and were the primary source of TSH in the tumor microenvironment. TSH released by moDCs promoted proliferation and invasion of tumors with high TSHR expressions, such as thyroid cancers and glioma. TSH also induced tumor programmed death-ligand 1 (PD-L1) expression through the TSHR-AC-PKA-JNK-c-JUN pathway. TSHR inhibitors reversed tumor immune evasion by inhibiting PD-L1 expression in tumor and myeloid cells and enhancing Teff activation.
Conclusions: TSH-TSHR axis promotes tumor evasion in thyroid cancers and glioma. TSH suppression therapy is an effective therapeutic strategy for combination in immune checkpoint blockades.
A universal in silico V(D)J recombination strategy for developing humanized monoclonal antibodies
Background: Humanization of mouse monoclonal antibodies (mAbs) is crucial for reducing their immunogenicity in humans. However, humanized mAbs often lose their binding affinities. Therefore, an in silico humanization method that can prevent the loss of the binding affinity of mAbs is needed.
Methods: We developed an in silico V(D)J recombination platform in which we used V(D)J human germline gene sequences to design five humanized candidates of anti-tumor necrosis factor (TNF)-α mAbs (C1-C5) by using different human germline templates. The candidates were subjected to molecular dynamics simulation. In addition, the structural similarities of their complementarity-determining regions (CDRs) to those of original mouse mAbs were estimated to derive the weighted interatomic root mean squared deviation (wRMSDi) value. Subsequently, the correlation of the derived wRMSDi value with the half maximal effective concentration (EC50) and the binding affinity (KD) of the humanized anti-TNF-α candidates was examined. To confirm whether our in silico estimation method can be used for other humanized mAbs, we tested our method using the anti-epidermal growth factor receptor (EGFR) a4.6.1, anti-glypican-3 (GPC3) YP9.1 and anti-α4β1 integrin HP1/2L mAbs.
Results: The R2 value for the correlation between the wRMSDi and log(EC50) of the recombinant Remicade and those of the humanized anti-TNF-α candidates was 0.901, and the R2 value for the correlation between wRMSDi and log(KD) was 0.9921. The results indicated that our in silico V(D)J recombination platform could predict the binding affinity of humanized candidates and successfully identify the high-affinity humanized anti-TNF-α antibody (Ab) C1 with a binding affinity similar to that of the parental chimeric mAb (5.13 × 10-10). For the anti-EGFR a4.6.1, anti-GPC3 YP9.1, and anti-α4β1 integrin HP1/2L mAbs, the wRMSDi and log(EC50) exhibited strong correlations (R2 = 0.9908, 0.9999, and 0.8907, respectively).
Conclusions: Our in silico V(D)J recombination platform can facilitate the development of humanized mAbs with low immunogenicity and high binding affinities. This platform can directly transform numerous mAbs with therapeutic potential to humanized or even human therapeutic Abs for clinical use.
Rubisco Mouse Polyclonal Antibody |
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100ul | 124 EUR |
Rubisco Mouse Polyclonal Antibody |
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50ul | 74 EUR |
Rubisco Mouse Polyclonal Antibody(Large Chain) |
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100ul | 319 EUR |
Rubisco Mouse Polyclonal Antibody(Large Chain) |
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100ul | 302.4 EUR |
Rubisco Mouse Polyclonal Antibody(Large Chain) |
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50ul | 224.4 EUR |
Rubisco Mouse Polyclonal Antibody (Large Chain) |
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100μg/100μl | 255 EUR |
Rubisco Mouse Polyclonal Antibody (Large Chain) |
|
100μg/100μl | 225 EUR |
Rubisco Mouse Polyclonal Antibody (Large Chain) |
|
100μg/100μl | 225 EUR |
Rubisco Mouse Polyclonal Antibody(Large Chain) |
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each | 402 EUR |
Rubisco Mouse Polyclonal Antibody(Large Chain) |
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100ul | 379.2 EUR |