TY - JOUR
T1 - Mobilized peripheral blood CD34+ cells express more amphotropic retrovirus receptor than bone marrow CD34+ cells
AU - Bregni, Marco
AU - Di Nicola, Massimo
AU - Siena, Salvatore
AU - Belli, Nadia
AU - Milanesi, Marco
AU - Shammah, Suzy
AU - Ravagnani, Fernando
AU - Gianni, Alessandro M.
PY - 1998/3
Y1 - 1998/3
N2 - Background and Objective. The increased susceptibility to gene transfer by amphotropic retroviral vectors of mobilized peripheral blood (PB) CD34+ cells compared to their bone marrow (BM) counterparts may depend, among other factors, on the level of expression of the amphotropic receptor on the progenitor cell. Using a previously described flow cytometry strategy, we have studied retrovirus binding to mobilized CD34+ cells, derived from cancer patients treated with high-dose chemotherapy and growth factor(s), that are efficiently transduced by N2 retro-virus vector. Design and Methods. We measured the binding of the retrovirus to the cells using a rat monoclonal antibody reactive with the gp70 envelope glycoprotein, common to all replication-defective amphotropic retroviruses. Antibody-virus-cell complexes were indirectly labeled and analyzed by flow cytometry. We compared the binding of PA317-N2 vector to CD34+ cells derived from steady-state BM, steady-state PB and mobilized PB from cancer patients treated with high-dose chemotherapy and cytokine. Results. The fluorescence intensity of mobilized CD34+ cells was approximately one log higher than that of steady-state BM or PB CD34+ cells, indicating that the expression of the amphotropic receptor was increased. Moreover, the virus binding was proportional to the gene transfer rate, as assessed by G418 resistance into mobilized PB-derived CFU- GM. The increase in fluorescence intensity appeared to be restricted to CD34+ cell subset, neither CD2+ nor CD14+ cells bound the virus in an appreciable amount. Interpretation and Conclusions. Virus binding, as assessed by indirect immunofluorescence assay, is increased in mobilized CD34+ cells. The increased binding may contribute to their high susceptibility to retrovirus vector infection.
AB - Background and Objective. The increased susceptibility to gene transfer by amphotropic retroviral vectors of mobilized peripheral blood (PB) CD34+ cells compared to their bone marrow (BM) counterparts may depend, among other factors, on the level of expression of the amphotropic receptor on the progenitor cell. Using a previously described flow cytometry strategy, we have studied retrovirus binding to mobilized CD34+ cells, derived from cancer patients treated with high-dose chemotherapy and growth factor(s), that are efficiently transduced by N2 retro-virus vector. Design and Methods. We measured the binding of the retrovirus to the cells using a rat monoclonal antibody reactive with the gp70 envelope glycoprotein, common to all replication-defective amphotropic retroviruses. Antibody-virus-cell complexes were indirectly labeled and analyzed by flow cytometry. We compared the binding of PA317-N2 vector to CD34+ cells derived from steady-state BM, steady-state PB and mobilized PB from cancer patients treated with high-dose chemotherapy and cytokine. Results. The fluorescence intensity of mobilized CD34+ cells was approximately one log higher than that of steady-state BM or PB CD34+ cells, indicating that the expression of the amphotropic receptor was increased. Moreover, the virus binding was proportional to the gene transfer rate, as assessed by G418 resistance into mobilized PB-derived CFU- GM. The increase in fluorescence intensity appeared to be restricted to CD34+ cell subset, neither CD2+ nor CD14+ cells bound the virus in an appreciable amount. Interpretation and Conclusions. Virus binding, as assessed by indirect immunofluorescence assay, is increased in mobilized CD34+ cells. The increased binding may contribute to their high susceptibility to retrovirus vector infection.
KW - Amphotropic receptor
KW - CD34
KW - Gene transfer
KW - Retroviruses
KW - Stem cells
UR - http://www.scopus.com/inward/record.url?scp=0031970589&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0031970589&partnerID=8YFLogxK
M3 - Article
C2 - 9573673
AN - SCOPUS:0031970589
VL - 83
SP - 204
EP - 208
JO - Haematologica
JF - Haematologica
SN - 0390-6078
IS - 3
ER -