Transcriptional targeting of dendritic cells in gene gun-mediated DNA immunization favors the induction of type 1 immune responses

Abstract

Cutaneous dendritic cells (DC) are pivotal for the elicitation of antigen-specific immune responses following gene gun-mediated biolistic transfection of the skin. We transcriptionally targeted transgene expression to DC using vectors containing the murine fascin promoter (pFascin) to control antigen production and compared the immune response elicited with conventional DNA immunization using plasmid constructs with the ubiquitously active CMV promoter (pCMV). Biolistic transfection with pFascin initiated a marked type 1 immune response characterized by the occurrence of a large population of IFN-gamma-producing T helper (Th) cells in spleen and draining lymph nodes. Consistently, immunoglobulin production was dominated by IgG2a antibodies. In contrast, the humoral response after repeated administration of pCMV was strongly enhanced and characterized by a type 2-like isotype pattern (IgG1 > IgG2a). Cytokine production analysis in vitro indicated compartmentalization of the immune response, revealing large numbers of IL-4-producing Th cells in the lymph nodes and dominant presence of IFN-gamma-producing Th cells in the spleen. Biolistic transfection with pFascin, like immunization with pCMV, led to potent induction of cytotoxic T cells as was assessed by JAM test. Thus gene gun immunization with plasmids that focus transgene expression and antigen production specifically to DC propagates type 1-biased cellular immune responses.

Immunization with a Lentivector That Targets Tumor Antigen Expression to Dendritic Cells Induces Potent CD8 + and CD4 + T-Cell Responses

“…A similar result was obtained when the DCspecific fascin promoter was used in gene gun-mediated immunization (39). In this case the authors showed that the fascin promoter induced a Th1 immune response, whereas a constitutive CMV promoter led to a Th2 response (39). However, the CD11c promoter was ineffective compared to the CMV promoter or the keratinocyte-specific K14 promoter in another gene gun vaccination study (24).…”

“…The same dectin-2 gene promoter has also been used in gene gun-mediated delivery of plasmid DNA, and in this case it also induced cellular immune responses (31). A similar result was obtained when the DCspecific fascin promoter was used in gene gun-mediated immunization (39). In this case the authors showed that the fascin promoter induced a Th1 immune response, whereas a constitutive CMV promoter led to a Th2 response (39).…”

A newly established murine immature dendritic cell line can be differentiated into a mature state, but exerts tolerogenic function upon maturation in the presence of glucocorticoid

“…22 ELISA capture Abs for murine IFN-␥ (clone R4-6A2) and IL-4 (11B11) were purchased from BD Pharmingen; Ab for murine IL-10 (JES052A5) was obtained from R&D Systems. Biotinylated detection Abs for IFN-␥ (XMG1.2) and IL-4 (BVD6-24G2) were obtained from BD Pharmingen, and Ab to IL-10 (BAF417) was obtained from R&D Systems.…”

Insufficient APC Capacities of Dendritic Cells in Gene Gun-Mediated DNA Vaccination

“…Therefore, the cellular localization of the expressed Ag might influence both magnitude as well as quality of responses (14 -17). As a consequence from this apparently prominent role of DC in DNA vaccination, several groups used DC-specific promoters (17,18) to enhance DNA vaccination efficacy by specifically targeting DC. However, most DNA vaccination studies investigating these types of vaccines either lack in vivo data or were based on i.m.…”