Microchip Screening Platform for Single Cell Assessment of NK Cell Cytotoxicity.
Here, we report a screening platform for assessment of the cytotoxic potential of individual natural killer (NK) cells within larger populations. Human primary NK cells were distributed across a silicon-glass microchip containing 32,400 individual microwells loaded with target cells. Through fluorescence screening and automated image analysis, the numbers of NK and live or dead target cells in each well could be assessed at different time points after initial mixing. Cytotoxicity was also studied by time-lapse live-cell imaging in microwells quantifying the killing potential of individual NK cells. Although most resting NK cells (≈75%) were non-cytotoxic against the leukemia cell line K562, some NK cells were able to kill several (≥3) target cells within the 12-h long experiment. In addition, the screening approach was adapted to increase the chance to find and evaluate serial killing NK cells. Even if the cytotoxic potential varied between donors, it was evident that a small fraction of highly cytotoxic NK cells were responsible for a substantial portion of the killing. We demonstrate multiple assays where our platform can be used to enumerate and characterize cytotoxic cells, such as NK or T cells. This approach could find use in clinical applications, e.g., in the selection of donors for stem cell transplantation or generation of highly specific and cytotoxic cells for adoptive immunotherapy.
Science for Life Laboratory, Department of Applied Physics, KTH - Royal Institute of Technology , Solna , Sweden.
Karolin
K
Guldevall
Science for Life Laboratory, Department of Applied Physics, KTH - Royal Institute of Technology , Solna , Sweden.
Ludwig
L
Brandt
Science for Life Laboratory, Department of Applied Physics, KTH - Royal Institute of Technology, Solna, Sweden; Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.
Elin
E
Forslund
Science for Life Laboratory, Department of Applied Physics, KTH - Royal Institute of Technology , Solna , Sweden.
Karl
K
Olofsson
Science for Life Laboratory, Department of Applied Physics, KTH - Royal Institute of Technology , Solna , Sweden.
Thomas W
TW
Frisk
Science for Life Laboratory, Department of Applied Physics, KTH - Royal Institute of Technology , Solna , Sweden.
Per E
PE
Olofsson
Science for Life Laboratory, Department of Applied Physics, KTH - Royal Institute of Technology , Solna , Sweden.
Karin
K
Gustafsson
Science for Life Laboratory, Department of Applied Physics, KTH - Royal Institute of Technology , Solna , Sweden.
Otto
O
Manneberg
Science for Life Laboratory, Department of Applied Physics, KTH - Royal Institute of Technology , Solna , Sweden.
Bruno
B
Vanherberghen
Science for Life Laboratory, Department of Applied Physics, KTH - Royal Institute of Technology , Solna , Sweden.
Hjalmar
H
Brismar
Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet , Stockholm , Sweden.
Klas
K
Kärre
Center for Allogeneic Stem Cell Transplantation, Huddinge University Hospital, Karolinska Institute, Stockholm, Sweden; Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden.
Michael
M
Uhlin
Science for Life Laboratory, Department of Applied Physics, KTH - Royal Institute of Technology, Solna, Sweden; Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.
Björn
B
Önfelt
NK cells; cytotoxicity; fluorescence; immune synapse; microchip; microscopy; screening; single cell analysis