Immunomagnetic T Cell Depletion: an Analysis of Variables Affecting Final Cell Yield.
BACKGROUND
Only little detailed information has been published by a small number of centers on experiences with the technical aspects of "in vitro" large-scale graft manipulation technologies.


METHODS
We report our experiences with the graft engineering procedures performed and the results obtained after T cell depletion. We have analyzed data from 212 procedures (108 CD34+ cell selection and 104 CD3+/CD19+ cell depletion).


RESULTS
We conclude that the final cell products after selection or depletion were completely different with regard to CD34+ cell purity (95.8% vs. 1.52%). The CD34+ cell recovery after CD34+ cell selection is negatively affected when the initial leukocyte and/or CD34+ cell counts exceed the threshold defined by the manufacturer (68.9% vs. 45.2%, p < 0.01). However, the cell count threshold defined for the depletion technique could be exceeded without seriously affecting final results (86.1% vs. 86.4% for those with more or less than 40 x 109 leukocyte before the procedure; p = 0.7). Another important conclusion from this study is that in both CD34+ cell selection and CD3+/CD19+ cell depletion better results were reached after having gained experience by performing the procedures several times. This means that a learning process can be expected when using these in vitro graft manipulation procedures.


CONCLUSIONS
It is extremely important to have experienced staff to perform these procedures. The expected results are different with each procedure so the decision on which of these T cell depletion approaches are used should be based on the characteristics of the final product wanted.
Julian
J
Sevilla
Maria
M
Guillen
Eva
E
Galvez
Eva
E
Merino
Ana
A
Castillo
Marta
M
Prudencio
Marta
M
Gonzalez-Vicent
Manuel
M
Ramirez
Lorea
L
Abad
Luis
L
Madero
Miguel A
MA
Diaz-Perez
D064591:Allografts; D018941:Antigens, CD19; D018952:Antigens, CD34; D017252:CD3 Complex; D005434:Flow Cytometry; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D018189:Immunomagnetic Separation; D059032:Learning Curve; D018655:Lymphocyte Count; D008212:Lymphocyte Depletion / Q000379:methods*; D010976:Platelet Count; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology
D018941:Antigens, CD19; D018952:Antigens, CD34; D017252:CD3 Complex