Rv2299c, a novel dendritic cell-activating antigen ofMycobacterium tuberculosis, fused-ESAT-6 subunit vaccine confers improved and durable protection against the hypervirulent strain HN878 in mice

Abstract

Understanding functional interactions between DCs and antigens is necessary for achieving an optimal and desired immune response during vaccine development. Here, we identified and characterized protein Rv2299c (heat-shock protein 90 family), which effectively induced DC maturation. The Rv2299c-maturated DCs showed increased expression of surface molecules and production of proinflammatory cytokines. Rv2299c induced these effects by binding to TLR4 and stimulating the downstream MyD88-, MAPK- and NF-κB-dependent signaling pathways. The Rv2299c-maturated DCs also showed an induced Th1 cell response with bactericidal activity and expansion of effector/memory T cells. The Rv2299c-ESAT-6 fused protein had greater immunoreactivity than ESAT-6. Furthermore, boosting BCG with the fused protein significantly reduced hypervirulent Mycobacterium tuberculosis HN878 burdens post-challenge. The pathological study of the lung from the challenged mice assured the efficacy of the fused protein. The fused protein boosting also induced Rv2299c-ESAT-6-specific multifunctional CD4+ T-cell response in the lungs of the challenged mice. Our findings suggest that Rv2299c is an excellent candidate for the rational design of an effective multiantigenic TB vaccine.

Mycobacterium avium subsp. paratuberculosis MAP1889c Protein Induces Maturation of Dendritic Cells and Drives Th2-Biased Immune Responses

“…In the present study, MAP1889c-treated DCs also induced T cell proliferation with higher IL-10 and IL-4 production, expansion of IL-10-producing T cells, and expression of GATA-3 in MLR assays (Figures 6 and 7). In many studies, naïve T cell proliferation experiments with mature DC are typically performed using an ovalbumin (OVA)-specific transgenic mouse model [16,41]. This mouse model was not available in our laboratory.…”

Mycobacterium tuberculosisProtein Rv3841 Activates Dendritic Cells and Contributes to a T Helper 1 Immune Response

“…Bone marrow-derived dendritic cells (BMDCs) and bone marrow-derived macrophages (BMDMs) were differentiated in vitro from isolated bone marrow cells from uninfected 5-6-week-old C57BL/6 mice. The cells were generated and cultured as recently described [ 28 ]. Briefly, using BMDC differentiation method, bone marrow cells collected from mouse femurs and tibias were incubated for 7 d in RPMI media supplemented with 10% fetal bovine serum (FBS), penicillin/streptomycin (100 unit/mL), nonessential amino acids (0.1 mM), β -mercaptoethanol (50 μ M), sodium pyruvate (1 mM), GM-CSF (20 ng/mL), and IL-4 (10 ng/mL).…”

“…Then, these T-cells were stained with 1 μ M CFSE (Invitrogen). T-cell proliferation assay was performed as recently described [ 28 ]. Briefly, DCs were treated with the OVA peptide from Peptron (Daejeon, Korea) and 10 μ g/mL of Rv3841 for 24 h. After that, Rv3841-activated DCs were cocultured with CFSE-stained T-cells at DC : T-cell ratios of 1 : 10.…”

“…Cytokines were quantified in culture supernatants using a sandwich enzyme-linked immunosorbent assay (ELISA) as described previously [ 28 ].…”

Expression of Toll-Like Receptor 2 by Dendritic Cells Is Essential for the DnaJ-ΔA146Ply-Mediated Th1 Immune Response against Streptococcus pneumoniae

“…DC maturation induced by TLRs plays important roles in protective immunity conferred by protein-based vaccines (15)(16)(17)(18). For instance, Mycobacterium tuberculosis-derived protein Rv2299c led to DC maturation through TLR4 and induced Th1 cell responses (19). A novel TLR2 agonist derived from Bordetella pertussis, lipoprotein BP1569, activated DCs via TLR2 and enhanced Th1, Th17, and IgG2a antibody responses in mice (20).…”