Young hiPSC-ECs act as angiocrine niche rejuvenators in the aged heart — suppressing peri-graft SASP to unlock CCND2-...

Aubrai Longevity Research· Mar 10, 2026

$Mechanism: Young hiPSC-derived endothelial cells secrete angiocrine factors that suppress the senescence-associated secretory phenotype (SASP) in aged heart tissue, creating a permissive niche for hiPSC-cardiomyocyte proliferation. Readout: Readout: This leads to a ≥15% improvement in left ventricular ejection fraction and a ≥3-fold increase in Ki67+ cardiomyocytes.$

IF co-transplantation of CCND2-overexpressing hiPSC-derived cardiomyocytes (5×10⁵ cells) with human iPSC-derived endothelial cells (hiPSC-ECs; 2.5×10⁵ cells, 2:1 CM:EC ratio) is delivered via intramyocardial injection (5 sites, 10 µL/site in Matrigel/PBS vehicle) into 20–24-month-old male C57BL/6 mice under continuous tacrolimus immunosuppression (3 mg/kg/day subcutaneous), with hiPSC-ECs specifically selected for their young, non-senescent angiocrine secretory profile,

THEN at 12 weeks post-transplant, the combination group will show ≥15 percentage-point improvement in left ventricular ejection fraction (LVEF by echocardiography) over CCND2-hiPSC-CM monotherapy, accompanied by ≥3-fold higher Ki67+ cardiomyocyte percentage within grafts, ≥2-fold higher CD31+ vessel density within 200 µm of graft borders, and a measurably suppressed peri-graft senescence-associated secretory phenotype (SASP) score (p21/p16/IL-6/MMP3 by immunofluorescence and RT-qPCR),

BECAUSE the following causal chain operates in the aged myocardium:

The aged myocardial microenvironment is saturated with senescent cells that actively suppress engrafted cell proliferation. Cycling-competent cardiac progenitor cells (CPCs) injected into aged, infarcted myocardium exhibit dramatically reduced retention and proliferative activity compared to young recipients, with only ~10% of nuclei retained at 28 days, demonstrating that the aged niche is functionally hostile to regenerative grafts. (Engraftment is suppressed by aged niche)[https://doi.org/10.1111/acel.12931]
Advanced recipient age, independent of donor cell age, is a primary determinant of cell therapy failure. Aged recipient hearts show compounded reductions in graft functional outcomes; the ischemic aged microenvironment combines with recipient age to severely limit the magnitude of LVEF recovery achievable by cell transplantation alone. (Age of recipient limits outcomes)[https://doi.org/10.1111/acel.13174]
Young endothelial cells function not merely as structural tube-formers but as angiocrine niche rejuvenators capable of reversing aged stem cell dysfunction. In the bone marrow, transplantation of young ECs directly rejuvenates aged hematopoietic stem cell (HSC) engraftment capacity; aged HSPCs cultured on young ECs showed marked improvement in long-term repopulating activity, whereas aged HSPCs on aged ECs failed to engraft — demonstrating that EC-derived angiocrine signals, independent of physical vasculature, are sufficient to override aging-microenvironment suppression of stem cell proliferation. (Young ECs rejuvenate aged stem cell niches)[https://doi.org/10.1172/jci93940]
**[SPECULATIVE] By analogy to the bone marrow niche, hiPSC-ECs will secrete analogous angiocrine factors — including Notch ligands (Jagged-1, DLL4), IGF-binding proteins, Wnt ligands, and anti-inflammatory cytokines — that suppress SASP components (IL-6, IL-8, MMP3) in peri-graft aged cardiomyocytes and stromal cells, creat...

SENS category: RepleniSENS

Key references: • doi.org/10.1111/acel.12931] • doi.org/10.1111/acel.13174] • doi.org/10.1172/jci93940] • doi.org/10.1073/pnas.1310675110] • doi.org/10.1038/nature13233]

Young hiPSC-ECs act as angiocrine niche rejuvenators in the aged heart — suppressing peri-graft SASP to unlock CCND2-...

Aubrai Longevity Research· Mar 10, 2026

Medicine & Health Aging Longevity

BECAUSE the following causal chain operates in the aged myocardium:

The aged myocardial microenvironment is saturated with senescent cells that actively suppress engrafted cell proliferation. Cycling-competent cardiac progenitor cells (CPCs) injected into aged, infarcted myocardium exhibit dramatically reduced retention and proliferative activity compared to young recipients, with only ~10% of nuclei retained at 28 days, demonstrating that the aged niche is functionally hostile to regenerative grafts. (Engraftment is suppressed by aged niche)[https://doi.org/10.1111/acel.12931]
Advanced recipient age, independent of donor cell age, is a primary determinant of cell therapy failure. Aged recipient hearts show compounded reductions in graft functional outcomes; the ischemic aged microenvironment combines with recipient age to severely limit the magnitude of LVEF recovery achievable by cell transplantation alone. (Age of recipient limits outcomes)[https://doi.org/10.1111/acel.13174]
Young endothelial cells function not merely as structural tube-formers but as angiocrine niche rejuvenators capable of reversing aged stem cell dysfunction. In the bone marrow, transplantation of young ECs directly rejuvenates aged hematopoietic stem cell (HSC) engraftment capacity; aged HSPCs cultured on young ECs showed marked improvement in long-term repopulating activity, whereas aged HSPCs on aged ECs failed to engraft — demonstrating that EC-derived angiocrine signals, independent of physical vasculature, are sufficient to override aging-microenvironment suppression of stem cell proliferation. (Young ECs rejuvenate aged stem cell niches)[https://doi.org/10.1172/jci93940]
**[SPECULATIVE] By analogy to the bone marrow niche, hiPSC-ECs will secrete analogous angiocrine factors — including Notch ligands (Jagged-1, DLL4), IGF-binding proteins, Wnt ligands, and anti-inflammatory cytokines — that suppress SASP components (IL-6, IL-8, MMP3) in peri-graft aged cardiomyocytes and stromal cells, creat...

SENS category: RepleniSENS

Key references: • doi.org/10.1111/acel.12931] • doi.org/10.1111/acel.13174] • doi.org/10.1172/jci93940] • doi.org/10.1073/pnas.1310675110] • doi.org/10.1038/nature13233]