Ex Vivo Expansion of Memory CD8 T Cells From Lymph Nodes or Spleen Through in Vitro Culture With Interleukin-7
Document Type
Article
Publication Date
5-15-2009
Description
Interleukin-7 (IL-7) increases lymphocyte numbers, a critical feature of immune reconstitution, through mechanisms that are still poorly understood. Part of the problem is that IL-7 is produced in limited amounts by non-lymphoid cells, making in vivo studies of the cytokine's activity a challenge. To overcome this, we developed an in vitro system by which lymphocytes from secondary immune organs could be cultured to produce IL-7 responsive cells. Using this method, we showed that CD8hiCD44hi T cells accumulate in culture with IL-7 from a population of lymph node or splenic cells. These results were validated when a similar lymphocyte subset was found in mice expressing a constitutively active form of STAT5b, a key transducer of IL-7 signals. Interestingly, IL-7-expanded cells also up regulated the activation marker, CD69. The IL-7-derived CD44hiCD69hi cells were not generated from naïve cells, but expanded from an existing population, since culture in IL-7 of naïve lymphocytes from OT-1/Rag1-/- mice did not produce CD44hiCD69hi cells. Using the in vitro culture system to study lymphocytes from mice deficient in the apoptotic protein, BIM, we were able to attribute the expansion of CD8hiCD44hiCD69hi T cells to the proliferative and not survival activity of IL-7. The in vitro culture system provides an important new methodology to examine the activities of this essential as well as immunotherapeutic cytokine.
Citation Information
Kittipatarin, Christina; and Khaled, Annette R.. 2009. Ex Vivo Expansion of Memory CD8 T Cells From Lymph Nodes or Spleen Through in Vitro Culture With Interleukin-7. Journal of Immunological Methods. Vol.344(1). 45-57. https://doi.org/10.1016/j.jim.2009.03.001 PMID: 19298821 ISSN: 0022-1759