Chimeric NKG2D receptor-expressing T cells as an immunotherapy for multiple myeloma.
OBJECTIVE
Most myeloma tumor cells from patients express NKG2D ligands. We have reported the development of a chimeric NKG2D receptor (chNKG2D), which consists of the NKG2D receptor fused to the CD3zeta chain. T cells expressing this receptor kill and produce cytokines in response to NKG2D-ligand+ tumor cells. Therefore, we investigated whether human chNKG2D T cells respond against human myeloma cells.


METHODS
ChNKG2D T cells were generated from healthy donors and myeloma patients. The effector phase of chNKG2D T cells was analyzed by cell-surface marker expression and human myeloma cell lines were tested for expression of NKG2D ligands. Lysis of myeloma cell lines and cytokine secretion by chNKG2D T cells was determined. ChNKG2D T cells grown in serum-free media, or cyropreserved, were assessed for effector cell functions.


RESULTS
Myeloma cell lines expressed NKG2D ligands. ChNKG2D T cells from healthy donors and myeloma patients lysed myeloma cells, and secreted proinflammatory cytokines when cultured with myeloma cells or patient bone marrow, but not with peripheral blood mononuclear cells or normal bone marrow. Lysis of myeloma cells was dependent on chNKG2D T-cell expression of NKG2D and perforin. Additionally, chNKG2D T cells upregulated CD45RO, did not express CD57, and maintained expression of CD27, CD62L, and CCR7, indicating that the T cells were at an early effector stage. Finally, we showed that chNKG2D T cells generated with serum-free media, or when cryopreserved, maintained effector functions.


CONCLUSIONS
ChNKG2D T cells respond to human myeloma cells and can be generated using clinically applicable cell culture techniques.
Barber
Amorette
A
Department of Microbiology and Immunology, Dartmouth Medical School, Dartmouth Hitchcock Medical Center, Lebanon, NH 03756, USA.
Zhang
Tong
T
Megli
Christina J
CJ
Wu
Jillian
J
Meehan
Kenneth R
KR
Sentman
Charles L
CL
D001402:B-Lymphocytes / Q000276:immunology; D001854:Bone Marrow Cells / Q000166:cytology / Q000473:pathology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D045744:Cell Line, Tumor; D005434:Flow Cytometry; D006801:Humans; D007167:Immunotherapy / Q000379:methods; D009101:Multiple Myeloma / Q000188:drug therapy / Q000382:microbiology* / Q000473:pathology; D055655:NK Cell Lectin-Like Receptor Subfamily K / Q000235:genetics* / Q000627:therapeutic use; D015514:Oncogene Proteins, Fusion / Q000627:therapeutic use*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000276:immunology*
C527085:KLRK1 protein, human; D055655:NK Cell Lectin-Like Receptor Subfamily K; D015514:Oncogene Proteins, Fusion