IF anti-IL-11 monoclonal antibody (X203, 20 mg/kg biweekly, subcutaneous) is co-administered with rapamycin (encapsulated in diet, 14 ppm) to aged (20-month-old) C57BL/6J mice,

THEN a synergistic reduction in existing senescent cell burden and a hyper-additive extension of remaining lifespan (exceeding the ~25% median extension of X203 alone) will be observed, measured via SA-β-gal staining in solid tissues and Kaplan-Meier survival curves,

BECAUSE:

1. Aberrant mTOR/p70S6K activation persists in senescent cells due to defects in amino acid sensing and mitochondrial stress (mTOR activation in senescence)[https://doi.org/10.1016/j.exger.2014.11.004], which rapamycin partially suppresses to dampen the Senescence-Associated Secretory Phenotype (SASP) without actively clearing the cells (mTORC1 persistence)[https://doi.org/10.1083/jcb.201610113].
2. Mitochondrial dysfunction in these persistent senescent cells elevates ROS and activates JNK/53BP1 inflammatory retrograde signaling (retrograde signaling)[https://doi.org/10.1101/gad.331272.119], driving a pro-inflammatory IL-11 feedback loop.
3. Neutralizing IL-11 specifically disrupts this pro-survival, age-upregulated inflammatory loop [SPECULATIVE], acting not merely as a redundant mTOR inhibitor, but by accelerating the actual removal/apoptosis of existing senescent cells, addressing the age-related drop in senescent cell clearance rates (accumulation mechanisms)[https://doi.org/10.1007/s11357-020-00286-x].
4. Combining SASP/production suppression (rapamycin) with active targeted senolysis (anti-IL-11) yields a complementary "prevent spread + clear existing" damage repair synergy.

One-liner: Combining anti-IL-11 therapy with rapamycin will synergistically clear accumulated senescent cells and extend lifespan by pairing targeted senolysis with systemic SASP suppression.

SENS category: MitoSENS

Key references: • doi.org/10.1016/j.exger.2014.11.004], • doi.org/10.1083/jcb.201610113]. • doi.org/10.1101/gad.331272.119], • doi.org/10.1007/s11357-020-00286-x]. • doi.org/10.1016/j.exger.2014.11.004].