Biology subjects

Franco-Obregon, A.

Publications and source records attributed to Franco-Obregon, A..

3 recordsLinked to original sources

bioRxiv2025

Modeling Adeno-Associated Viral Vector 6-mediated In Vivo Gene Delivery to Expanded Non-Mobilized Haemopoietic Stem Cells from Transfusion dependent Thalassemia Patients in a Humanized Mouse

Hematopoietic stem cells (HSC) are important targets for gene modification therapies (GMT) as they originate several serious genetic conditions including the {beta}-haemoglobinopathies. Potentially curative ex vivo GMT pose the barriers of accessibility, myeloablation-associated morbidity and prohibitive cost. In vivo GMT using non-integrating single-strand adeno-associated viral vectors (ssAAV) are a promising alternative that address these challenges directly, although the small ssAAV payload limits the capacity to package much larger gene or base editors. We investigated the feasibility of targeting human HSC in vivo with a dual-ssAAV6 strategy, which in future may be useful to deliver split-intein editing tools to overcome this limitation. We engrafted NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ humice with human hCD45+CD34+ HSC from transfusion-dependent {beta}-thalassemic patients to test in vivo targeting of hCD45 cells with ssAAV6, then administered 5E+12 genomes/kg of ssAAV6-GFP/ssAAV6-mCherry. Humice showed peak single-transgene expression (GFP+ or mCh+) of 1.96-10.17%, and dual-transgene expression (GFP+mCh+) of 31.77% in circulating hCD45+ cells. Nested hCD45+ from liver, spleen and bone marrow showed single-and dual-transgene expression of 36.13-68.14% and 21.91-59.44% respectively. Secondary transplantation experiments demonstrated long-term persistence of AAV6-transduced hCD45 cells showing single-and dual-transgene expression of 9.19-60.72% and 7.15-9.19% respectively, with significant increase in expression from circulating cells. Minimal pro-inflammatory cytokine expression was observed following ssAAV6 administration in thalassemia humice compared with humice carrying non-thalassemia HSC. Our model demonstrates the efficiency of in vivo ssAAV6-mediated targeting of thalassaemia HSC, potential long-term survivability of transduced cells, and feasibility of a dual-AAV strategy for gene editing, which offers a promising alternative to ex vivo GMT for {beta}-haemoglobinopathies.

molecular biology↗

bioRxiv2021

Modulated TRPC1 expression predicts sensitivity of breast cancer to doxorubicin and magnetic field therapy: segue towards a precision medicine approach.

BackgroundChemotherapy is the mainstream treatment modality for invasive breast cancer. Nonetheless, chemotherapy-associated adverse events can result in a patient terminating treatment. We show that transient receptor potential channel 1 (TRPC1) expression level predicts breast cancer sensitivity to doxorubicin (DOX) and pulsed electromagnetic field (PEMF) therapies. MethodsThe effects of PEMFs were examined with respect to: 1) the growth of MCF-7 cells in vitro; 2) MCF-7 tumors implanted into a chicken chorioallantoic membrane (CAM) model and; 3) patient-derived and MCF-7 breast cancer xenografts in mice. Potential synergisms between DOX and PEMF therapies were examined in these model systems and under conditions of TRPC1 overexpression or silencing in vitro. ResultsPEMF exposure impaired the survival of MCF-7 cells, but not that of nonmalignant MCF10A breast cells. The effects of PEMF- and DOX-therapies synergized in vitro at compromising MCF-7 cell growth. Synergism could be corroborated in vivo with patient-derived xenograft mouse models, wherein PEMF exposure alone or in combination with DOX reduced tumor size. Stable overexpression of TRPC1 enhanced the vulnerability of MCF-7 cells to both DOX and PEMF exposure and promoted proliferation, whereas chronic DOX exposure reduced TRPC1 expression, induced chemoresistance, precluded response to PEMF exposure and mitigated proliferation. Markers of metastasis including SLUG, SNAIL, VIMENTIN, and E-CADHERIN as well as invasiveness were also positively correlated with TRPC1 channel expression. ConclusionThe presented data supports a potential role of PEMF-therapy as an effective companion therapy to DOX-based chemotherapy for the treatment of breast cancers characterized by elevated TRPC1 expression levels.

cancer biology↗

bioRxiv2020

Cell-Derived Vesicles as TRPC1 Channel Delivery Systems for the Recovery of Cellular Respiratory and Proliferative Capacities

Pulsed electromagnetic fields (PEMFs) are capable of specifically activating a TRPC1-mitochondrial axis underlying cell expansion and mitohormetic survival adaptations. This study characterizes cell-derived vesicles (CDVs) generated from C2C12 murine myoblasts and shows that they are equipped with the sufficient molecular machinery to confer mitochondrial respiratory capacity and associated proliferative responses upon their fusion with recipient cells. CDVs derived from wild type C2C12 myoblasts include the cation-permeable transient receptor potential (TRP) channels, TRPC1 and TRPA1, and directly respond to PEMF exposure with TRPC1-mediated calcium entry. By contrast, CDVs derived from C2C12 muscle cells in which TRPC1 had been genetically knocked-down using CRISPR/Cas9 genome editing, do not. Wild type C2C12-derived CDVs are also capable of restoring PEMF-induced proliferative and mitochondrial activation in two C2C12-derived TRPC1 knockdown clonal cell lines in accordance to their endogenous degree of TRPC1 suppression. C2C12 wild type CDVs respond to menthol with calcium entry and accumulation, likewise verifying TRPA1 functional gating and further corroborating compartmental integrity. Proteomic and lipidomic analyses confirm the surface membrane origin of the CDVs providing an initial indication of the minimal cellular machinery required to recover mitochondrial function. CDVs hence possess the potential of restoring respiratory and proliferative capacities to senescent cells and tissues.

cell biology↗