Generation of immature autologous clinical grade dendritic cells for vaccination of cancer patients.
BACKGROUND
Dendritic cell (DC)-based vaccine is a promising approach for cancer therapy. Pioneer trials have been conducted using DC generated in research conditions. There is now a need for generating DC in clinical grade conditions, including the use of closed systems, avoidance of FCS and respect of good manufacturing practices (GMP).


METHODS
DC were generated from 84 leukapheresis products of 27 cancer patients enrolled in two Phase I/II trials of vaccination of either MAGE+tumors (n = 24) or prostate cancer (n = 3). Monocytes were seeded in culture bags in a serum-free medium supplemented with IL-4 and GM-CSF. After a 7 day culture, DC were collected and most were pulsed with various MAGE-derived peptides.


RESULTS
After a short leukapheresis (mean time: 66 min; mean processed blood: 5 L), a mean of 6 x 10(9) WBC were collected, from which 2.25 x 10(9) were seeded. The culture procedure yielded a large number of DC (mean: 62 x 10(6) DC) harboring the expected phenotype of immature DC (CD1a(+) CD14(-) HLA-DR(+) CD80(+) CD86(+) CD83(-)). This phenotype was not altered by peptide loading. These DC, either fresh or thawed, were functionally effective invitro. Their s.c. and i.v. injections were devoid of any short-term side effect and associated with the induction of immune responses in the patients.


CONCLUSIONS
Large numbers of functional immature clinical grade DC can be generated in a closed system from leukapheresis products in cancer patients. These results provide the basis for large-scale studies of cancer immunotherapy under improved safety conditions.
Toungouz
M
M
Cellular and Molecular Therapy Unit, Erasme Hospital, 808 Route de Lennik, B-1070 Brussels, Belgium.
Quinet
C
C
Thille
E
E
Fourez
S
S
Pradier
O
O
Delville
J P
JP
Velu
T
T
Lambermont
M
M
D000328:Adult; D000368:Aged; D000951:Antigens, Neoplasm / Q000096:biosynthesis; D019496:Cancer Vaccines / Q000627:therapeutic use*; D017690:Cell Transplantation / Q000379:methods*; D064987:Cell- and Tissue-Based Therapy / Q000379:methods; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D003713:Dendritic Cells / Q000166:cytology*; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism; D006801:Humans; D007167:Immunotherapy / Q000379:methods; D015847:Interleukin-4 / Q000378:metabolism; D007937:Leukapheresis / Q000379:methods; D008297:Male; D058950:Melanoma-Specific Antigens; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000096:biosynthesis; D009369:Neoplasms / Q000276:immunology* / Q000628:therapy*; D010455:Peptides / Q000737:chemistry; D011471:Prostatic Neoplasms / Q000628:therapy
D000951:Antigens, Neoplasm; D019496:Cancer Vaccines; D016895:Culture Media, Serum-Free; C072011:MAGEA1 protein, human; D058950:Melanoma-Specific Antigens; D009363:Neoplasm Proteins; D010455:Peptides; D015847:Interleukin-4; D016178:Granulocyte-Macrophage Colony-Stimulating Factor