Dendritic cells (DCs) can initiate immune responses or confer immune tolerance depending on functional status. Lipopolysaccharide (LPS) induced DC maturation as defined by enhanced surface expression of CD80 and CD86. MicroRNAs (miRNAs) are critical for the regulation of DC function and immunity, and the miRNA let-7i was up-regulated during LPS-induced DC maturation. Down-regulation of let-7i significantly impeded DC maturation as evidenced by reduced CD80 and CD86 expression. DCs stimulated by LPS (LPS-DCs) promoted T-cell proliferation in co-culture, while LPS-stimulated DCs with down-regulated let-7i were not effective at stimulating T cell proliferation but promoted expansion of the regulatory T cell (Treg) population. There were two subpopulations of LPS-stimulated DCs with down-regulated let-7i, CD86- and CD86+, and it was the CD86- DCs that were more effective in inducing T cell hyporesponsiveness and enhancing Treg numbers, indicating that this DC population had tolerogenic properties. Furthermore, Treg with up-regulated IL-10 underscored the tolerogenic effect of CD86- DCs. Suppressor of cytokine signalling 1 (SOCS1), a crucial mediator of DC maturation, was confirmed as a let-7i target gene by luciferase construct assay. Suppression or overexpression of let-7i caused reciprocal alterations in SOCS1 protein expression, but had no significant effects on SOCS1 mRNA levels, indicating that let-7i regulated SOCS1 expression by translational suppression. The modulation of SOCS1 protein by let-7i was mainly restricted to CD86- DCs. Our study demonstrates that let-7i regulation of SOCS1 is critical for LPS-induced DC maturation and immune function. Dynamic regulation of let-7i may fine tune immune responses by inducing antigen-specific immune tolerance.
CXXC5 is a newly identified CXXC-type zinc finger family protein, which is encoded by the CXXC5 gene localised to the 5q31.3 chromosomal region. Previous studies revealed that CXXC5 is associated with various malignant tumours. The aim of the present study was to investigate the prognosis prediction of CXXC5 in different breast cancer subtypes via the Gene Expression Omnibus database and bc-GenExMiner. CXXC5 overexpression was observed as associated with a poor prognosis for oestrogen receptor positive (ER+) breast cancer. Basal-like breast cancer and triple-negative breast cancer also suggest a poor prognosis, however their CXXC5 expression was low and could not be used as a prognostic factor. The CXXC5 correlated genes and their enriched Gene Ontology (GO) terms were obtained. Among those enriched GO terms, GO:0070062 (extracellular exosome) had the greatest number of associated genes and the associated genes of GO:0000122 (negative regulation of transcription from RNA polymerase II promoter) and GO:0008134 (transcription factor binding) contained CXXC5. These results suggest that overexpression of CXXC5 is a strongly poor prognostic factor in ER+ breast cancer. However, the role of CXXC5 in breast cancer requires further investigation.
Abstract Neoantigen vaccines and adoptive dendritic cell (DC) transfer are major clinical approaches to initiate personalized immunity in cancer patients. However, the immunization efficacy is largely limited by the in vivo trajectory including neoantigens’ access to resident DCs and DCs’ access to lymph nodes (LNs). Herein, an innovative strategy is proposed to improve personalized immunization through neoantigen‐loaded nanovaccines synergized with adoptive DC transfer. It is found that it enables selective delivery of neoantigens to resident DCs and macrophages by coating cancer cell membranes onto neoantigen‐loaded nanoparticles. In addition, the nanovaccines promote the secretion of chemokine C‐C motif ligand 2 (CCL2), CCL3, and C‐X‐C motif ligand 10 from macrophages, thus potentiating the access of transferred DCs to LNs. This immunization strategy enables coordinated delivery of identified neoantigens and autologous tumor lysate‐derived undefined antigens, leading to initiation of antitumor T cell immunity in a personalized manner. It significantly inhibits tumor growth in prophylactic and established mouse tumor models. The findings provide a new vision for potentiating adoptive cell transfer by nanovaccines, which may open the door to a transformative possibility for improving personalized immunization.
Lung metastasis is challenging in patients with triple-negative breast cancer (TNBC). Surgery is always not available due to the dissemination of metastatic foci and most drugs are powerless because of poor retention at metastatic sites. TNBC cells generate an inflamed microenvironment and overexpress adhesive molecules to promote invasion and colonization. Herein, "walking dead" TNBC cells are developed through conjugating anti-PD-1 (programmed death protein 1 inhibitor) and doxorubicin (DOX)-loaded liposomes onto cell corpses for temporal chemo-immunotherapy against lung metastasis. The walking dead TNBC cells maintain plenary tumor antigens to conduct vaccination effects. Anti-PD-1 antibodies are conjugated to cell corpses via reduction-activated linker, and DOX-loaded liposomes are attached by maleimide-thiol coupling. This anchor strategy enables rapid release of anti-PD-1 upon reduction conditions while long-lasting release of DOX at inflamed metastatic sites. The walking dead TNBC cells improve pulmonary accumulation and local retention of drugs, reprogram the lung microenvironment through damage-associated molecular patterns (DAMPs) and PD-1 blockade, and prolong overall survival of lung metastatic 4T1 and EMT6-bearing mice. Taking advantage of the walking dead TNBC cells for pulmonary preferred delivery of chemotherapeutics and checkpoint inhibitors, this study suggests an alternative treatment option of chemo-immunotherapy to augment the efficacy against lung metastasis.
Almost all life activities of plants are accompanied by electrophysiological information. Plant's electrical parameters are considered to be the fastest response to environment. In this study, the theoretically intrinsic relationships between the clamping force and leaf resistance (R) and inductive reactance (XL) were revealed as 3-parameter exponential decay based on bioenergetics for the first time. The intrinsic resistance (IR), capacitive reactance (IXc), inductive reactance (IXL), impedance (IZ), and capacitance (IC) in plant leaves were successfully monitored. The nutrient flux per unit area (UNF), nutrient transfer rate (NTR) and nutrient transport capacity (NTC) in plants based on IR, IXc, IXL, IZ and IC were defined to reflect nutrient transport characteristics. The results indicate that IXc and IXL could be used to manifest the relative composition characteristics of cell membrane proteins, and are inversely proportional to the amount of surface and binding proteins that induce membrane Xc and XL in plant leaves, respectively. UNF, NTR or NTC exhibited good correlations with crude protein or crude ash, and accurately revealed the nutrient transport strategies of tested plants and their diversity. This study highlights that plant's electrophysiological information could effectively manifest the composition and nutrient transport characteristics of membrane proteins in plant cells.
Delta-like ligand 3 (DLL3) is ectopically expressed on the cell surface of various neuroendocrine tumors including small cell lung cancer (SCLC) and other neuroendocrine tumors, but shows minimal expression in normal adult tissue. DLL3-CD3 bispecific T cell engager Tarlatamab has received accelerated approval for the treatment of extensive stage small cell lung cancer (ES-SCLC). However, poor T cell infiltration in the SCLC tumor microenvironment may limit the clinical activity of CD3 engagers. Here, we present the development of DLL3-TOPAbody, a trispecific T cell engager that binds to DLL3 on the cancer cells and engages CD3 and 4-1BB on the T cells, which could redirect enhanced T cell responses to DLL3-expressing tumor cells while maintaining a manageable safety profile. This approach has the potential to improve clinical outcomes for SCLC patients, particularly those with poorly infiltrated tumors.
Methods
In vitro cytotoxicity and T cell activation mediated by DLL3-TOPAbody were further assessed in multiple DLL3+ tumor cell lines in coculture with effector cells. Anti-tumor activity was investigated in a humanized syngeneic mice model bearing B16F10-hDLL3 tumors. Safety assessment including cytokine release assay (CRA) was also performed.
Results
DLL3-TOPAbody demonstrated DLL3-dependent CD3 and 4-1BB downstream signaling. Moreover, DLL3-TOPAbody effectively induced tumor lysis in multiple DLL3+ tumor cell lines and demonstrated significantly enhanced cytokine production and T cell proliferation in the presence of DLL3-expressing target cells. In a humanized syngeneic tumor mouse model, DLL3-TOPAbody demonstrated superior tumor growth inhibition compared to Tarlatamab. Efficacy was observed in the immunologically cold tumor, which is resistant to PD-1 treatment. In addition, administration of the DLL3-TOPAbody induced a more immune-inflammatory phenotype in the tumor microenvironment. In vitro cytokine release assay suggested that IL-6 release in the DLL3-TOPAbody group was comparable to that in the Tarlatamb group, indicating a manageable risk of inducing cytokine release syndrome (CRS).
Conclusions
DLL3-TOPAbody represents a novel DLL3-targeted T cell engager with potent and durable anti-tumor activity. Together, these results underscore the potential of DLL3-TOPAbody as a novel therapeutic agent against DLL3+ cancers and support its advancement into clinical development.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)