Immunization route dictates cross-priming efficiency and impacts the optimal timing of adjuvant delivery

Abstract

Delivery of cell-associated antigen represents an important strategy for vaccination. While many experimental models have been developed in order to define the critical parameters for efficient cross-priming, few have utilized quantitative methods that permit the study of the endogenous repertoire. Comparing different strategies of immunization, we report that local delivery of cell-associated antigen results in delayed T cell cross-priming due to the increased time required for antigen capture and presentation. In comparison, delivery of disseminated antigen resulted in rapid T cell priming. Surprisingly, local injection of cell-associated antigen, while slower, resulted in the differentiation of a more robust, polyfunctional, effector response. We also evaluated the combination of cell-associated antigen with poly I:C delivery and observed an immunization route-specific effect regarding the optimal timing of innate immune stimulation. These studies highlight the importance of considering the timing and persistence of antigen presentation, and suggest that intradermal injection with delayed adjuvant delivery is the optimal strategy for achieving CD8+ T cell cross-priming.

Systemic Toll-Like Receptor Ligation and Selective Killing of Dendritic Cell Subsets Fail To Dissect Priming Pathways for Anti-Vaccinia Virus CD8+T Cells

“…This is unlike the situation of immunization of mice after CpG treatment, where a virus must be able to infect and have its antigens processed and presented by DCs that matured many hours previously. We expect that our findings have implications for the use of other TLR ligands, such as synthetic polyinosinic·poly(C) [poly(I·C)] double-stranded RNA and lipopolysaccharide (LPS), which have been suggested to inhibit cross-presentation in vivo (12,45). Finally, there is no obvious reason why our data obtained with VACV and VACV-infected cells would not apply equally to other viruses.…”

Intradermal Immunization with rAAV1 Vector Induces Robust Memory CD8+ T Cell Responses Independently of Transgene Expression in DCs

“…47,48 Enhanced cross-presentation of cell-associ-ated antigen following local (intradermal) rather than systemic (intravenous) delivery has been described in the context of a membranebound OVA model antigen. 49 Our results suggest that this might represent a unique property of the skin not shared by all other peripheral tissues, including the skeletal muscle. The potency of skin-expressed transgene cross-presentation further suggests that efficient induction of memory CTL responses should solely depend on the ability of a given vector to drive antigen expression in non-hematopoietic skin cells.…”

HLA-A*01:03, HLA-A*24:02, HLA-B*08:01, HLA-B*27:05, HLA-B*35:01, HLA-B*44:02, and HLA-C*07:01 Monochain Transgenic/H-2 Class I Null Mice: Novel Versatile Preclinical Models of Human T Cell Responses

“…Determination of AV and BV gene usage were performed as described previously (41). In brief, real-time quantitative PCRs were performed individually for each TCR BV and AV segment family with a complete set of TCR BV (42) and TCR AV (Supplemental Table I) forward primers at a final concentration of 400 nM/l each. When necessary (DNA sequence polymorphism of AV family segment members), appropriate forward primers were mixed.…”

“…When necessary (DNA sequence polymorphism of AV family segment members), appropriate forward primers were mixed. PCRs were carried out on an ABI-7300 system (Applied Biosystem, Carlsbad, CA) combining reverse constant TCR BC (5′-GGTA-GCCTTTTGTTTGTTTGCAA-3′) and reverse constant TCR AC (5′-GGC-ACATTGATTTCCTGGCTATTGC-3′) primers (400 nM/l final concentration) and BC (5′-AGCCATCAAAAGCAA-3′) or AC (5′-CTTCTGCCTGTTCA-CCGA-3′) MGB-TaqMan probes at a 200 nM/l final concentration (Life Technology, Carlsbad, CA) as previously described (42). The relative usage in percentage of each BV and AV family was calculated according to the following formula: $$\begin{array}{c}leftx=21\\ U(\mathit{AVy})=\sum 2^{(Ct(x)\mathit{XCt}(y))}\\ x=1\end{array}$$ and…”