bioRxiv Science⌕ Search

Biology subjects

McCarthy, E. C.

Publications and source records attributed to McCarthy, E. C..

4 recordsLinked to original sources

Investigation of immune response to Mesenchymal Stromal Cell-derived Extracellular Vesicles in the cancer setting

Mesenchymal Stromal Cell derived extracellular vesicles (MSC-EVs) may retain the cancer targeting and immune privilege of MSCs. The immense potential MSC-EVs hold as tumour-targeted therapeutics warrants an understanding of potential adverse events to support clinical translation. This study aimed to determine whether MSC-EVs would elicit an immune response following administration in tumour-bearing immunocompetent animals. Secreted EVs were isolated from both human and murine bone marrow derived MSCs and characterized. hMSC-EVs or mMSC-EVs were administered intravenously into 4T1 breast tumour-bearing Balb/c mice or healthy controls. Tumour tissue, draining lymph nodes and spleens were harvested, dissociated into a single cell suspension and flow cytometry performed targeting T cells, myeloid derived suppressor cells (MDSCs), macrophages, dendritic cells and natural killer (NK) cells. The 4T1 model immune profile was first determined by comparing the spleen of tumour-bearing animals to healthy controls. T cells were increased in tumour-bearing animals (CD4+/CD25+ p=0.041; CD8+/CD25+ p=0.02). A significant elevation of GR-1+ MDSCs (p=0.002), CD11b+ macrophages (p=0.023) and CD11c+ dendritic cells (p=0.001) was also observed. In contrast, CD27+ NK cells were significantly decreased compared to the spleen of healthy animals (p=0.006). Collectively this data validated the immune profile and supported the determination of any changes in response to hMSC-EVs or mMSC-EVs administration. No significant activation of CD4+ (p=0.20) or CD8+ (p=0.57) T cells were seen in tumour tissue in both groups. The percentage of GR-1+ MDSCs (28% vs 27%, p=0.92), CD11b+, CD11c+ and CD27+ cells were similar regardless of EV origin. No significant changes in T cells, MDSCs, macrophages, dendritic or NK cells were observed in the lymph node or spleen of animals that received hMSC-EV versus mMSC-EVs. In conclusion, human MSC-EVs elicited no discernible immune response in mice, supporting the hypothesis that MSC-EVs retain the immune privilege of the secretory cell. This reinforces the therapeutic potential of MSC-EVs.

cancer biology↗

miR-379-3p counteracts cancer cachexia through regulation of pyrimidinergic receptor, mitochondrial stress and interferon response.

Cancer cachexia is a highly prevalent wasting syndrome in cancer patients. Inflammation is hallmarks of symptomatic cachexia, however early stages of cachexia are not well understood, including differences between biological sexes. In a mouse model of early cachexia, muscle from males showed strong mitochondrial defects, whereas females were characterized by inflammatory and stress response. We demonstrate a novel link between the increase in purinergic receptor P26Y, and dysregulated Ca2+ homeostasis, mitochondrial dysfunction and damage, and inflammation during early stages of cancer cachexia. Low levels of miR-379-3p were associated with poor survival of patients with lung cancer. Restoring miR-379-3p levels in mice prevented loss of muscle mass and function. miR-379-3p targeted P2r6y and restored mitochondrial content and function, inhibited type II interferon response, and regulated the expression of Ca2+-related and apoptotic markers. This supports miR-379-3p as a hub regulating multiple processes underlying cachexia and represent a therapeutic target for cancer patients.

cancer biology↗

Mechanobiological cues to bone cells during early metastasis drive later osteolysis: a computational mechanoregulation framework prediction

Bone cells contribute to tumour metastasis by producing biochemical factors that stimulate tumour cell homing and proliferation, but also by resorbing bone matrix (osteolysis) that releases further stimulatory factors for tumour growth in a vicious cycle. Changes in the local mechanical environment of bone tissue occur during early metastasis, which might activate mechanobiological responses by resident bone cells (osteocytes) to activate resorption (osteoclasts) and thereby contribute to tumour invasion. The objective of this study is to investigate whether bone osteolysis is driven by early changes in the bone mechanical environment during metastasis by (a) implementing subject-specific FE models of metastatic femora to predict the mechanical environment within bone tissue during early metastasis (3-weeks after tumour inoculation) and then (b) applying mechanoregulation theory to predict bone tissue remodelling as a function of the evolving mechanical environment within bone tissue during breast cancer-bone metastasis. We implemented a global resorption rate derived from an experimental model, but the mechanoregulation algorithm predicted localised bone loss in the greater trochanter region, the same region where osteolysis was prevalent after three weeks of metastasis development in the animal model. Moreover, the mechanical environment evolved in a similar manner to that reported in separate subject-specific finite element models of these same animals by 6 weeks. Thus, we propose that early changes in the physical environment of bone tissue during metastasis may elicit mechanobiological cues for bone cells and activate later osteolytic bone destruction.

cancer biology↗

Inhibition of the IL-17A axis Protects against Immune-related Adverse Events while Supporting Checkpoint Inhibitor Anti-tumor Efficacy

Checkpoint inhibitor (ICI) immunotherapy leverages the bodys own immune system to attack cancer cells but leads to unwanted autoimmune side effects in up to 60% of patients. Such immune related adverse events (IrAE) may lead to treatment interruption, permanent organ dysfunction, hospitalization and premature death. Thyroiditis is one of the most common IrAE, but the cause of thyroid IrAE remains unknown. Here we present a novel mouse model in which checkpoint inhibitor therapy leads to multi-organ autoimmune infiltrates and show that activation and infiltration of Type 3 immune cells including IL17A+ ROR{gamma}t+ CD4+ (T helper 17 or Th17) and gamma delta 17 ({gamma}{delta}T17) T cells promote thyroid IrAE development. IL-17A+ T cells were similarly found in thyroid specimens from cancer patients treated with ICI who developed thyroid IrAE. Furthermore, antibody-based inhibition of IL-17A, a clinically available therapy, significantly reduced thyroid IrAE development in ICI-treated mice. Finally, combination of IL-17A neutralization with ICI treatment in multiple tumor models did not reduce ICI anti-tumor efficacy. These studies suggest that targeting Th17 and {gamma}{delta}17 function may reduce IrAE without impairing ICI anti-tumor efficacy and may be a generalizable strategy to address IL17-mediated IrAE.

immunology↗