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November 06-07, 2019 | Tokyo, Japan
Volume 02
Journal of Clinical Genetics and Genomics
STEM CELLS AND REGENERATIVE MEDICINE
PEDIATRICS AND CHILD CARE
International Conference on
2
nd
World Congress on
&
J Clin Gen Genomics, Volume 02
Stem Cells 2019 & Pediatrics Congress 2019
November 06-07, 2019
Regeneration of the immune system to fight leukemia at relapse post alloHSCT
The use of allogeneic hematopoietic stem cell transplantation inAML patients suffering from intermediate and high-risk disease
was the real breakthrough in improvement of treatment results. AlloHSCT offers rebuilding of the normal hematopoiesis ruined
by leukemia and chemotherapy as well as regeneration of the immune systemwhich after transplantation has the immune system
potential of healthy donor what also means that if exposed to leukemic blasts may identify them as alien. Therefore, allogeneic
hematopoietic stem cell transplantation makes the immune response against the transplanted patient cells including the blasts
possible. If the immune response is not effective enough the donor lymphocytes may be infused (DLI). This approach proved
to be effective especially in chronic myelogenous leukemia and in some indolent lymphomas but not good enough in AML.
Unfortunately, DLI associates with a considerably toxicity with acceleration of the graft vs host process as a main cause.
Having under our observation an ALL patient who relapsed after alloHSCT with leukemic infiltrations of the bones but not the
marrowwe injected the donor cells directly to the bone lesions with a positive effect. To exploit this approach further we started a
project on the use of intra-bone route for injection of donor lymphocytes directly to the marrow cavity at relapse - thus providing
the direct contact between the leukemic cells and the fresh lymphocytes from which those seeing blasts may be recruited.
Nine patients they relapsed after alloHSCT entered the experimental group having as counter-partners the patients they received
at relapse standard therapy. The aim of the project was to evaluate the feasibility of the use of intra bone route and also to
identify the cells which boosted in their potential by IB-DLI might be involved in anti-leukemic effect in other words in graft vs
leukemia. The observation led to the following conclusions:
• The intra-bone route proved to be convenient and free from unwanted effects.
• The lymphocyte used for infusion were taken from the primary transplant material (stimulated) or obtained de novo from
the blood with the use of leukophoresis (unstimulated), both cell populations except of the content of CD34+ cells did not
differ especially the proportion of CD3+ cells was very similar.
• Local anesthesia and low molecular heparin secured that infusion procedure was undisturbed
• The patients which received IB-DLI enjoyed better 12- and 18-months survival as compared to those on standard therapy
(77% vs 11%, p=0.006 and 55% vs 11%, p=0.035, respectively).
Andrzej Lange
Lower Silesian Center for Cellular Transplantation with National Bone Marrow Donor Registry, Poland