Maturation pathways of dendritic cells in vivo: Distinct function, phenotype and localization of lymphoid- and myeloid-derived dendritic cell subsets in FLT3-ligand treated mice

The analysis of the development and function of distinct subsets of murine dendritic cells (DC) has been hampered by the limited number of these cells in vivo. To circumvent this limitation we have developed a conditional transgenic mouse model for producing large numbers of DC. We used the tetracycline-inducible system to conditionally express murine Flt3 ligand (FL), a potent hemopoietic growth factor that promotes the differentiation and mobilization of DC. Acute treatment (96 h) of the transgenic animals with the tetracycline analog doxycycline (DOX) promoted an ∼200-fold increase in serum levels of FL without affecting the number of circulating DC. However, within 1 wk of DOX treatment, the relative number of DC in peripheral blood increased from ∼8 to ∼40%. Interestingly, both the levels of FL and the number of DC remained elevated for at least 9 mo with continual DOX treatment. Chronic treatment of the mice with DOX led to dramatic increases in the number of DC in multiple tissues without any apparent pathological consequences. Most DC populations were expanded, including immature and mature DC, myeloid (CD11c+CD11b+CD8a−), lymphoid (CD11c+CD11b−CD8a+), and the recently defined plasmacytoid (pDC) subsets. Finally, transplantation of BM from green fluorescent protein-expressing mice into lethally irradiated transgenic mice followed by subsequent DOX treatment led to expansion of green fluorescent protein-labeled DC. The transgenic mice described here should thus provide a readily available source of multiple DC subsets and should facilitate the analysis of their role in homeostasis and disease.

Section: Discussionmentioning

confidence: 99%

“…It is well established that exogenous treatment of mice with hFL induces the expansion of DC in blood and several tissues (5,10,11). Therefore, having detected expression of the responder transgene in multiple tissues and high circulating levels of mFL, we examined the DC numbers in Tg mice.…”

Section: Conditional Expression Of Fl Leads To Expansion Of Cd11c ϩ Cmentioning

confidence: 99%

Conditional Expression of Murine Flt3 Ligand Leads to Expansion of Multiple Dendritic Cell Subsets in Peripheral Blood and Tissues of Transgenic Mice

Manfra¹,

Chen²,

Jensen³

et al. 2003

“…Unaltered DC subtypes and maturation/activation status in lpr/lpr mice DCs in murine secondary lymphoid organs have been classified into two main subtypes: myeloid and lymphoid (51,(55)(56)(57)(58)(59). These two DC types have been proposed to take opposing roles in T cell activation and tolerance, although this remains controversial (60 -64).…”

Section: Altered DC Localization and Increased Frequency/numbers In Lmentioning

confidence: 99%

“…These two DC types have been proposed to take opposing roles in T cell activation and tolerance, although this remains controversial (60 -64). Myeloid DCs are marked by expression of CD11c, CD11b, and 33D1, and within the spleen resting myeloid DCs are concentrated at the bridging channels to the red pulp (51,56). These DCs enter the PALS upon activation and terminal maturation (49,65,66).…”

Section: Altered DC Localization and Increased Frequency/numbers In Lmentioning

confidence: 99%

Fas/Fas Ligand Deficiency Results in Altered Localization of Anti-Double-Stranded DNA B Cells and Dendritic Cells

Fields

Sokol

Eaton-Bassiri

et al. 2001

Autoantibodies directed against dsDNA are found in patients with systemic lupus erythematosus as well as in mice functionally deficient in either Fas or Fas ligand (FasL) (lpr/lpr or gld/gld mice). Previously, an IgH chain transgene has been used to track anti-dsDNA B cells in both nonautoimmune BALB/c mice, in which autoreactive B cells are held in check, and MRL-lpr/lpr mice, in which autoantibodies are produced. In this study, we have isolated the Fas/FasL mutations away from the autoimmune-prone MRL background, and we show that anti-dsDNA B cells in Fas/FasL-deficient BALB/c mice are no longer follicularly excluded, and they produce autoantibodies. Strikingly, this is accompanied by alterations in the frequency and localization of dendritic cells as well as a global increase in CD4 T cell activation. Notably, as opposed to MRL-lpr/lpr mice, BALB-lpr/lpr mice show no appreciable kidney pathology. Thus, while some aspects of autoimmune pathology (e.g., nephritis) rely on the interaction of the MRL background with the lpr mutation, mutations in Fas/FasL alone are sufficient to alter the fate of anti-dsDNA B cells, dendritic cells, and T cells.

“…Splenic DC can be divided phenotypically and functionally into two distinct populations, CD8␣ Ϫ and CD8␣ ϩ DC. The CD8␣ Ϫ cells are myeloid DC (MDC), and the CD8␣ ϩ cells are lymphoid DC (LDC) (5)(6)(7)(8)(9)(10). Although both populations can induce CD4 ϩ T cell proliferation in vitro, MDC are better inducers of CD4 ϩ T cell proliferation (7).…”

Section: S Ince the First Description Of Dendritic Cells (Dc) 3 In 1973mentioning

confidence: 99%

Dendritic Cells in the Induction of Protective and Nonprotective Anticryptococcal Cell-Mediated Immune Responses

Bauman

Nichols

Murphy

2000

Dendritic cells (DC) can be divided into three subsets, Langerhans cells, myeloid DC (MDC), and lymphoid DC (LDC), based upon phenotypic and functional differences. We hypothesized that different DC subsets are associated with the development of protective vs nonprotective cell-mediated immune (CMI) responses against the fungal pathogen, Cryptococcus neoformans. To test this, mice were immunized with protective and/or nonprotective immunogens, and DC subsets in draining lymph nodes were assessed by flow cytometry. The protective immunogen (cryptococcal culture filtrate Ag-CFA), in contrast to the nonprotective immunogen (heat-killed cryptococci-CFA), the nonprotective immunogen mixed with the protective immunogen (cryptococcal culture filtrate Ag + heat-killed cryptococci-CFA), or controls, stimulated significant increases in total leukocytes, Langerhans cells, MDC, LDC, and activated CD4+ T cells in draining lymph nodes. The protective immune response resulted in significantly increased levels of anticryptococcal delayed-type hypersensitivity reactivity and activated CD4+ T cells at the delayed-type hypersensitivity reaction site. Draining lymph node LDC:MDC ratios induced by the protective immunogen were significantly lower than the ratios induced by either immunization in which the nonprotective immunogen was present. In contrast, mice given the nonprotective immunogen had LDC:MDC ratios similar to those of naive mice. Our data indicate that lymph node Langerhans cells and MDC are APC needed for induction of the protective response. The predominance of LDC in mice undergoing nonprotective responses suggests that lymph node LDC, like splenic LDC, are negative regulators of CMI responses. In addition to showing DC subsets associated with functional differences, our data suggest that the LDC:MDC balance, which can be modulated by the Ag, determines whether protective or nonprotective anticryptococcal CMI responses develop.