In bone marrow transplantation (BMT), hematopoiesis-reconstituting cells are introduced
following myeloablative treatment, which eradicates existing hematopoietic cells and
disrupts stroma within the hematopoietic tissue. Both hematopoietic cells and stroma
then undergo regeneration. Our study compares the outcomes of a second BMT administered
to mice shortly after myeloablative treatment and the first BMT, with those of a second
BMT administered to mice experiencing robust hematopoietic regeneration after the
initial transplant. We evaluated the efficacy of the second BMT in terms of engraftment
efficiency, types of generated blood cells, and longevity of function. Our findings
show that regenerating hematopoiesis readily accommodates newly transplanted stem
cells, including those endowed with a robust capacity for generating B and T cells.
Importantly, our investigation uncovered a window for preferential engraftment of
transplanted stem cells coinciding with the resumption of blood cell production. Repeated
BMT could intensify hematopoiesis reconstitution and enable therapeutic administration
of genetically modified autologous stem cells.
