Differential Development of Murine Dendritic Cells by GM-CSF versus Flt3 Ligand Has Implications for Inflammation and Trafficking

Abstract

To gain ample numbers of dendritic cells (DCs) for investigation, or for immunotherapy, the culture of DC precursors from bone marrow in either GM-CSF and IL-4 (GM/IL4-DCs) or Flt3L (FL-DCs) has often been used. Despite their common use, the relationship of these culture-derived DCs to those in vivo, and their relative potential for use in immunotherapy, needs further elucidation. In this study we found that in contrast to FL-DCs, highly purified GM/IL4-DCs were larger and more granular, surface Mac-3+, and were comprised of two populations (CD24lowCD11bhigh and CD24highCD11blow). Functionally, although comparable in T cell activation, GM/IL4-DCs produced more inflammatory mediators including TNF-α, IL-10, CCL-2, and NO than FL-DCs upon TLR ligation. However, FL-DCs migrated more efficiently to draining lymph nodes after s.c. injection and produced a different profile of cytokines to GM/IL4-DCs. Developmentally, unlike GM/IL4-DCs, FL-DCs cannot be differentiated from CD11bhighLy6ChighLy6G− monocytes. Collectively, these data suggest that the GM/IL4-DCs are the equivalents of the TNF-α and inducible NO synthase producing DCs in vivo that emerge after inflammation whereas FL-DCs better represent the steady-state resident DCs. The differences between GM/IL4-DCs and FL-DCs have serious implications for DC-based immunotherapeutic strategies.

Microparticles released by Listeria monocytogenes-infected macrophages are required for dendritic cell-elicited protective immunity

“…22 Therefore, in this study, we used GM-CSF/IL-4-induced DCs to further confirm the involvement of macrophages in DCs presenting Lm antigen to T cells. Bone marrow-derived DCs were incubated with viable Lm (gentamicin was added 30 min later) in the presence or absence of peritoneal macrophages for various time intervals (6, 12 and 18 h).…”

Functional regulation of monocyte-derived dendritic cells by microRNAs

“…Recruitment of monocytes (moDC precursors) into inflammatory sites is largely dependent on CCR2 (Serbina and Pamer, 2006). Functionally, moDCs are major producers of pro-inflammatory cytokines (Serbina et al, 2003;Xu et al, 2007;Zhan et al, 2010), inducers of Th1 differentiation (Leon et al, 2007) and memory T cell activation (Wakim et al, 2008), and antigen cross-presenting cells (Cheong et al, 2010). By exhibiting these potent functions, moDCs offer a protective immunity role as well as mediate immunopathology (Aldridge et al, 2009).…”

“…With increasing knowledge of the presence of in vivo DC subsets, a question is which in vivo DC subset resembles the DCs generated in vitro in the presence of GM-CSF. By direct comparison of expression of surface markers and functions, it has been suggested that in vitro GM-CSF-differentiated DCs are the equivalents of in vivo moDCs that are capable of producing large quantities of TNF-α and inducible nitric oxide (NO) synthase emerging after infection (Xu et al, 2007). Despite that GM-CSF is a potent cytokine differentiating DCs from monocytes, how critical GM-CSF is for in vivo differentiation of moDCs is less clear.…”

“…Although all DCs are capable of producing cytokines in response to TLR and non-TLR stimulation, moDCs are particularly potent producers of pro-inflammatory cytokines (Xu et al, 2007). When different DC subsets were isolated from Listeria monocytogene-infected mice, moDCs were the dominant DC type to produce many pro-inflammatory cytokines (YZ, unpublished data).…”

Choose your models wisely: How different murine bone marrow-derived dendritic cell protocols influence the success of nanoparticulate vaccines in vitro

“…An additional critical factor that complicates the use of DCs in vitro, is the plethora of protocols that are available for the generation of these cells. The differentiation of bone marrow into BM-DCs can be achieved with either GM-CSF (Granulocyte-macrophage colony-stimulating factor) alone or in combination with IL-4 (interleukin-4), but also other factors, including Flt3L (FMS-related tyrosine kinase 3 ligand) or IL-3 have been employed at different concentration ratios [14,17,18]. Changing the cocktail and concentrations of cytokines can result in major differences in DC phenotype.…”