CD99-directed antibody-doxorubicin conjugate slows Ewing sarcoma xenografts
- A hybridoma IgM antibody against CD99 was converted to a recombinant IgG2a format made in CHO cells, keeping its specific CD99 recognition.
- The antibody promoted cell death and curbed growth of CD99-positive Ewing sarcoma cells in vitro.
- Linked to doxorubicin, it localised to and was retained in A673 xenografts.
- The conjugate suppressed tumour growth more than vehicle or antibody alone, with more necrosis and lower proliferation in tumour tissue.
💡 Points Based on the abstract
CD99 is a credible Ewing target, but it is also expressed on normal haematopoietic and endothelial cells, so I want to see binding data on those before any enthusiasm. The missing control is a non-targeting IgG-doxorubicin conjugate: without it, A673 xenograft benefit could be plain payload delivery via leaky vasculature. Next step: free-doxorubicin comparison at matched dose, plus cardiac readouts.
A recombinant CD99-targeted antibody–drug conjugate for Ewing sarcoma therapy ↗