title: Generation of highly cytotoxic natural killer cells for treatment of acute myelogenous leukemia using a feeder-free, particle-based approach.
abstract: Natural killer (NK) cell immunotherapy as a cancer treatment shows promise, but expanding NK cells consistently from a small fraction (∼ 5%) of peripheral blood mononuclear cells (PBMCs) to therapeutic amounts remains challenging. Most current ex vivo expansion methods use co-culture with feeder cells (FC), but their use poses challenges for wide clinical application. We developed a particle-based NK cell expansion technology that uses plasma membrane particles (PM-particles) derived from K562-mbIL15-41BBL FCs. These PM-particles induce selective expansion of NK cells from unsorted PBMCs, with NK cells increasing 250-fold (median, 35; 10 donors; range, 94 to 1492) after 14 days of culture and up to 1265-fold (n = 14; range, 280 to 4426) typically after 17 days. The rate and efficiency of NK cell expansions with PM-particles and live FCs are comparable and far better than stimulation with soluble 41BBL, IL-15, and IL-2. Furthermore, NK cells expand selectively with PM-particles to 86% (median, 35; range, 71% to 99%) of total cells after 14 days. The extent of NK cell expansion and cell content was PM-particle concentration dependent. These NK cells were highly cytotoxic against several leukemic cell lines and also against patient acute myelogenous leukemia blasts. Phenotype analysis of these PM-particle-expanded NK cells was consistent with an activated cytotoxic phenotype. This novel NK cell expansion methodology has promising clinical therapeutic implications.
authors.affiliation: Burnett School of Biomedical Sciences, University of Central Florida, College of Medicine, Orlando, Florida.
authors.forename: Jeremiah L
authors.initials: JL
authors.lastname: Oyer
authors.affiliation: Burnett School of Biomedical Sciences, University of Central Florida, College of Medicine, Orlando, Florida.
authors.forename: Robert Y
authors.initials: RY
authors.lastname: Igarashi
authors.affiliation: Burnett School of Biomedical Sciences, University of Central Florida, College of Medicine, Orlando, Florida.
authors.forename: Alexander R
authors.initials: AR
authors.lastname: Kulikowski
authors.affiliation: Burnett School of Biomedical Sciences, University of Central Florida, College of Medicine, Orlando, Florida.
authors.forename: Dominic A
authors.initials: DA
authors.lastname: Colosimo
authors.affiliation: Florida Hospital Cancer Institute, Orlando, Florida; University of Central Florida, College of Medicine, Orlando, Florida.
authors.forename: Melhem M
authors.initials: MM
authors.lastname: Solh
authors.affiliation: Florida Hospital Cancer Institute, Orlando, Florida.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Zakari
authors.affiliation: Florida Hospital Cancer Institute, Orlando, Florida.
authors.forename: Yasser A
authors.initials: YA
authors.lastname: Khaled
authors.affiliation: Burnett School of Biomedical Sciences, University of Central Florida, College of Medicine, Orlando, Florida.
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Altomare
authors.affiliation: Burnett School of Biomedical Sciences, University of Central Florida, College of Medicine, Orlando, Florida. Electronic address: alicja.copik@gmail.com.
authors.forename: Alicja J
authors.initials: AJ
authors.lastname: Copik
mesh_terms: D018929:Cell Culture Techniques; D049109:Cell Proliferation; D055252:Cell-Derived Microparticles / Q000276:immunology*; D005260:Female; D018922:HL-60 Cells; D006801:Humans; D007111:Immunity, Cellular; D020014:K562 Cells; D007694:Killer Cells, Natural / Q000276:immunology*; D015470:Leukemia, Myeloid, Acute / Q000276:immunology*; D008297:Male; D013997:Time Factors
keywords: AML; NK cell expansion; NK cells