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1.  A new synthetic TLR4 agonist, GLA, allows dendritic cells targeted with antigen to elicit Th1 T cell immunity in vivo 
European journal of immunology  2011;42(1):101-109.
SUMMARY
Protein-based vaccines offer safety and cost advantages but require adjuvants to induce immunity. Glucopyranosyl Lipid A (GLA) is a new synthetic non-toxic analogue of lipopolysaccharide. In mice, in comparison to non-formulated LPS and another analog Monophosphoryl Lipid A, formulated GLA induced higher antibody titers and generated Type 1 T cell responses to HIV gag-p24 protein in spleen and lymph nodes, which was dependent on TLR4 expression. Immunization was greatly improved by targeting HIV gag p24 to dendritic cells (DCs) within anti-DEC antibody, a DC receptor for antigen uptake and processing. Subcutaneous immunization induced antigen-specific T cell responses in the intestinal lamina propria. Immunity did not develop in mice transiently depleted of DCs. To understand how GLA works, we studied DCs directly from the vaccinated mice. Within 4 hrs, GLA caused DCs in vivo to upregulate CD86 and CD40 and produce cytokines including IL-12p70. Importantly, DCs removed from mice 4 hrs after vaccination became immunogenic, capable of inducing T cell immunity upon injection into naïve mice. These data indicate that a synthetic and clinically feasible TLR4 agonist rapidly stimulates full maturation of DCs in vivo and this allows for adaptive immunity to develop many weeks to months later.
doi:10.1002/eji.201141855
PMCID: PMC3517108  PMID: 22002164
Adjuvants; Vaccination; Dendritic cells; mucosal immunity; Innate Immunity
2.  Microbial stimulation fully differentiates monocytes to DC-SIGN/CD209+ dendritic cells for immune T cell areas 
Cell  2010;143(3):416-429.
SUMMARY
Dendritic cells (DCs), critical antigen presenting cells for immune control, normally derive from bone marrow precursors distinct from monocytes. It is not yet established if the large reservoir of monocytes can develop into cells with critical features of DCs in vivo. We now show that fully differentiated Mo-DCs develop in mice and DC-SIGN/CD209a marks the cells. Mo-DCs are recruited from blood monocytes into lymph nodes by lipopolysaccharide and live or dead gram negative bacteria. Mobilization requires TLR4 and its CD14 coreceptor and Trif. When tested for antigen presenting function, Mo-DCs are as active as classical DCs, including cross presentation of proteins and live gram negative bacteria on MHC I in vivo. Fully differentiated Mo-DCs acquire DC morphology and localize to T cell areas via L-selectin and CCR7. Thus the blood monocyte reservoir becomes the dominant presenting cell in response to select microbes, yielding DC-SIGN+ cells with critical functions of DCs.
doi:10.1016/j.cell.2010.09.039
PMCID: PMC3150728  PMID: 21029863
3.  New monoclonal anti-mouse DC-SIGN antibodies reactive with acetone-fixed cells 
Journal of immunological methods  2010;360(1-2):66-75.
Mouse DC-SIGN CD209a is a type II transmembrane protein, one of a family of C-type lectin genes syntenic and homologous to human DC-SIGN. Current anti-mouse DC-SIGN monoclonal antibodies (MAbs) are unable to react with DC-SIGN in acetone fixed cells, limiting the chance to visualize DC-SIGN in tissue sections. We first produced rabbit polyclonal PAb-DSCYT14 against a 14-aa peptide in the cytosolic domain of mouse DC-SIGN, and it specifically detected DC-SIGN and not the related lectins, SIGN-R1 and SIGN-R3 expressed in transfected CHO cells. MAbs were generated by immunizing rats and DC-SIGN knockout mice with the extracellular region of mouse DC-SIGN.. Five rat IgG2a or IgM MAbs, named BMD10, 11, 24, 25, and 30, were selected and each MAb specifically detected DC-SIGN by FACS and Western blots, although BMD25 was cross-reactive to SIGN-R1. Two mouse IgG2c MAbs MMD2 and MMD3 interestingly bound mouse DC-SIGN but at 10 fold higher levels than the rat MAbs. When the binding epitopes of the new BMD and two other commercial rat anti-DC-SIGN MAbs, 5H10 and LWC06, were examined by competition assays, the epitopes of BMD11, 24, and LWC06 were identical or closely overlapping while BMD10, 30, and 5H10 were shown to bind different epitopes. MMD2 and MMD3 epitopes were on a 3rd noncompeting region of mouse DC-SIGN. DC-SIGN expressed on the cell surface was sensitive to collagenase treatment, as monitored by polyclonal and MAb. These new reagents should be helpful to probe the biology of DC-SIGN in vivo.
doi:10.1016/j.jim.2010.06.006
PMCID: PMC2924951  PMID: 20558171
Monoclonal Antibody; Polyclonal Antibody; DC-SIGN; CD209a; Dendritic Cells

Results 1-3 (3)