CD40 ligand is necessary and sufficient to support primary diffuse large B-cell lymphoma cells in culture: A tool for in vitro preclinical studies with primary B-cell malignancies

Masonic Cancer Center, University of Minnesota, Minneapolis, MN 5455, USA.
Leukemia & lymphoma (Impact Factor: 2.89). 02/2012; 53(7):1390-8. DOI: 10.3109/10428194.2011.654337
Source: PubMed


Established cell lines are utilized extensively to study tumor biology and preclinical therapeutic development. However, they may not accurately recapitulate the heterogeneity of their corresponding primary disease. B-cell tumor cells are especially difficult to maintain under conventional culture conditions, limiting access to samples that faithfully represent this disease for preclinical studies. Here, we used primary canine diffuse large B-cell lymphoma to establish a culture system that reliably supports the growth of these cells. CD40 ligand, either expressed by feeder cells or provided as a soluble two-trimeric form, was sufficient to support primary lymphoma cells in vitro. The tumor cells retained their original phenotype, clonality and known karyotypic abnormalities after extended expansion in culture. Finally, we illustrate the utility of the feeder cell-free culture system for comparable assessment of cytotoxicity using dog and human B-cell malignancies. We conclude that this system has broad applications for in vitro preclinical development for B-cell malignancies.

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    • "Cryopreserved tumor cells obtained from sterile lymph node biopsy samples from dogs with diffuse large B cell lymphoma (DLBCL) were cultured with 100 ng/mL of megaCD40L (Enzo Life Science, Plymouth Meeting, PA) as previously described [26], [27]. The human T-cell leukemia cell line, Jurkat, was from the American Type Culture Collection (ATCC, Manassas, VA) and cultured in RPMI1640 medium (Gibco/BRL, Grand Island, NY) containing 10% fetal bovine serum (FBS; Atlas Biologicals, Fort Collins, CO), 2-mercaptoethanol (Gibco/BRL), HEPES, L-glutamine, sodium pyruvate (Mediatech Inc., Manassas, VA), non-essential amino acids (Sigma Aldrich, St. Louis, MO), and Primocin (Invivogen, San Diego, CA). "
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