Project description:B cells potentially play a role in the immune response to melanoma, including during treatment with immune modulators. We profiled effects of 3M-052 on gene expression in draining lymph nodes of syngeneic mice bearing B16 melanoma tumors. When B16 tumors reached 30-40 mm2 in size, they were injected intratumorally once with 3M-052 or vehicle control.
Project description:Class-switching to IgG2a/c in mice is a hallmark response to intracellular pathogens. T cells can promote class-switching and the predominant pathway for induction of IgG2a/c antibody responses has been suggested to be via stimulation from Th1 cells. We previously formulated CAF®01 (cationic liposomes containing dimethyldioctadecylammonium bromide (DDA) and Trehalose-6,6-dibehenate (TDB)) with the lipidated TLR7/8 agonist 3M-052 (DDA/TDB/3M-052), which promoted robust Th1 immunity in newborn mice. When testing this adjuvant in adult mice using the recombinant Chlamydia trachomatis (C.t.) vaccine antigen CTH522, it similarly enhanced IgG2a/c responses compared to DDA/TDB, but surprisingly reduced the magnitude of the IFN-g+ Th1 response in a TLR7 agonist dose-dependent manner. Single cell RNA-sequencing revealed that DDA/TDB/3M-052 liposomes initiated early transcription of class-switch regulating genes directly in pre-germinal center B cells. Mixed bone marrow chimeras further demonstrated that this adjuvant did not require Th1 cells for IgG2a/c switching, but rather facilitated TLR7-dependent T-bet programming directly in B cells. This study underlines that adjuvant-directed IgG2a/c class-switching in vivo can occur in the absence of T cell help, via direct activation of TLR7 on B cells and positions DDA/TDB/3M-052 as a powerful adjuvant capable of eliciting type I-like immunity in B cells without strong induction of Th1 responses.
Project description:Authorization of the Matrix-M-adjuvanted R21 vaccine by three countries and its subsequent endorsement by the World Health Organization (WHO) for malaria prevention in children is a milestone in the fight against malaria. Yet, to meet the unprecedented demand for malarial vaccines, there is a pressing need for additional adjuvants that induce robust and durable vaccine-induced immunity. Here, we performed a comparative assessment of three clinically relevant adjuvants (an alum formulation of the TLR7/8 agonist 3M-052 (3M-052+Alum), the TLR4 agonist GLA-LSQ (GLA in liposome QS-21 formulation), and Matrix-M, the currently approved adjuvant for R21) for their capacity to induce durable immune responses to the R21 malaria vaccine in non-human primates. Immunization of macaques with R21 adjuvanted with 3M-052+Alum on a 0, 8, and 24-week schedule elicited anti-circumsporozoite antibody responses comparable in magnitude to the R21/Matrix-M vaccine and persisted up to 72 weeks with a half-life of 337 (264 – 459) days. A booster dose at 72 weeks induced an antigen-specific recall response, similar to the R21/Matrix-M vaccination. In contrast, R21/GLA-LSQ immunization induced a considerably lower and short-lived response. Consistent with the durability of serum antibody responses, Matrix-M and 3M-052+Alum induced long-lived plasma cells in the bone marrow and other tissues, including the spleen, but GLA-LSQ stimulated only short-lived plasmablasts. Finally, we show distinct innate immune signatures early after vaccination with these adjuvants. While 3M-052+Alum stimulated potent and persistent antiviral transcriptional and cytokine signatures after primary and booster immunizations, Matrix-M induced an enhanced expression of interferon- and Th2-related signatures more highly after the booster vaccination. Collectively, these findings provide a comparative database on the immune responses of three clinically relevant adjuvants with R21 and highlight the promise of 3M-052+Alum as an additional adjuvant for the R21 malaria vaccine.
Project description:The purpose of this experiment was to assess the genes upregulated when pDCs were stimulated with TLR7 agonist imiquimod and TLR9 agonist CpG C.
Project description:The purpose of this experiment was to assess the genes upregulated when pDCs were stimulated with TLR7 agonist imiquimod and TLR9 agonist CpG C. pDCs were isolated from six healthy donors by FACS sorting, and were stimulated with CpG and imiquimod for 18 hours, after which RNA was extracted for next generation sequencing on the Illumina HiSeq platform. Unstimulated samples were included as controls.
Project description:Goal was to detect differences in response to TLR7 versus TLR8 agonists in human monocytes from healthy donors 3 deidentified donors from the Red Cross, monocytes from each donor incubated overnight with either vehicle, TLR7 agonist or TLR8 agonist
Project description:We investigated the effects of the TLR8 agonist 3M-002 on latently HIV infected U1 cells. We found a prominent upregulation of TLR-dependent genes. Notably, the TLR8 agonist resulted in a marked activation of HIV.
Project description:Treatment with the TLR7/8 agonist R848 results in a significant increase in classic dendritic cells (DCs) in the bone marrow, but a decrease in common dendritic cell progenitors and pre-DCs. Phenotypic analysis of DCs showed that R848 treatment is associated with altered expression of certain chemokines, activation markers, and migratory receptors.
Project description:Plasmacytoid dendritic cells (pDCs) can be activated by the endosomal TLRs, and contribute to the pathogenesis of systemic lupus erythematosus (SLE) by producing type I IFNs. Thus, blocking TLR-mediated pDC activation may represent a useful approach for the treatment of SLE. In an attempt to identify a therapeutic target for blocking TLR signaling in pDCs, we investigated the contribution of Bruton's tyrosine kinase (Btk) to the activation of pDCs by TLR7 and TLR9 stimulation by using a selective Btk inhibitor RN486. Stimulation of TLR7 and 9 with their respective agonist, namely, gardiquimod and type A CpG ODN2216, resulted in the activation of human pDCs, as demonstrated by the expression of activation markers (CD69, CD40, and CD86), elevated production of IFN-alpha and other inflammatory cytokines, as well as up-regulation of numerous genes including IFN-alpha-inducible genes and activation of interferon regulatory factor 7 (IRF7) and NF-kB. RN486 inhibited all of these events induced by TLR9, but not TLR7 stimulation, with a nanomolar potency for inhibiting type A CpG ODN2216-mediated production of cytokines (e.g., IC50=386 nM for inhibiting IFN-alpha). Our data reveal Btk as an important regulatory enzyme in the TLR9 pathway, and a potential therapeutic target for SLE and other TLR-driven diseases. pDCs from healthy donors (n=4) were treated with gardiquimod (TLR7 agonist) or ODN 2216 (TLR9 agonist) with or without BTK inhibitor for 3 hours.