Anti-GD3 chimeric sFv-CD28/T-cell receptor zeta designer T cells for treatment of metastatic melanoma and other neuroectodermal tumors.
OBJECTIVE
The aims of this study are to compare antitumor activities of two generations of GD3-specific chimeric antigen receptors (CAR) in human primary T lymphocytes in vitro and to evaluate the antitumor efficacy of using a combination of systemic infusion of interleukin-2 (IL2) and designer T cells to eradicate subcutaneous established GD3+ melanoma in nude mice.


METHODS
Antitumor activities were compared for two generations of designer T cells, the progenitor first-generation with immunoglobulin T-cell receptor (TCR) with Signal 1 and the second-generation designer T cells with Signal 1+2. Osmotic IL2 pumps were used to deliver the maximum tolerated dose of IL2 to enhance the antitumor effects of designer T cells on subcutaneous established melanoma in nude mice.


RESULTS
Melanoma is associated with high expression of ganglioside GD3, which has been targeted with modest effect in antibody therapies. We previously showed that an anti-GD3 CAR (sFv-TCRzeta) will recruit T cells to target this non-T-dependent antigen, with potent killing of melanoma cells. Here, we report the addition of a CD28 costimulation domain to create a second-generation CAR, called Tandem for two signals. We show that this Tandem sFv-CD28/TCRzeta receptor on T cells confers advantages of improved cytokine secretion, cytotoxicity, proliferation, and clonal expansion on tumor contact versus the same CAR without costimulation. In an adoptive transfer model using established melanoma tumors, designer T cells with CD28 showed a 50% rate of complete remissions but only where IL2 was supplemented.


CONCLUSIONS
As a reagent for clinical development, the second-generation product is shown to have superior properties to warrant its preference for clinical designer T-cell immunotherapy for melanoma and other tumors. Systemic IL2 was required for optimal activity in an established tumor model.
Lo
Agnes S Y
AS
Division of Surgical Research, Department of Surgery, Boston University School of Medicine, Roger Williams Medical Center, Providence, Rhode Island 02908, USA.
Ma
Qiangzhong
Q
Liu
David L
DL
Junghans
Richard P
RP
D000818:Animals; D015153:Blotting, Western; D018106:CD28 Antigens / Q000276:immunology*; D045744:Cell Line, Tumor; D002469:Cell Separation; D002678:Chimera; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D005434:Flow Cytometry; D005732:Gangliosides / Q000276:immunology*; D006801:Humans; D016219:Immunotherapy, Adoptive / Q000379:methods*; D007376:Interleukin-2; D008546:Melanoma, Experimental / Q000276:immunology / Q000628:therapy*; D051379:Mice; D008819:Mice, Nude; D017599:Neuroectodermal Tumors / Q000276:immunology / Q000628:therapy; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology / Q000637:transplantation; D014161:Transduction, Genetic; D023041:Xenograft Model Antitumor Assays
D018106:CD28 Antigens; D016207:Cytokines; D005732:Gangliosides; D007376:Interleukin-2; D011948:Receptors, Antigen, T-Cell; C026226:ganglioside, GD3