Toll-like receptors (TLRs) are germline-encoded pattern-recognition receptors that allow the innate immune system to detect conserved microbial structures and initiate the first line of host defense. Different TLRs survey distinct cellular compartments and ligand classes: cell-surface TLR4 recognizes bacterial lipopolysaccharide, whereas endosomal TLR3, TLR9, and related receptors sense viral double-stranded RNA and unmethylated CpG DNA, respectively. Ligand engagement induces receptor dimerization and recruitment of intracellular adaptors through Toll/IL-1 receptor (TIR) domain interactions. Most TLRs, with the notable exception of TLR3, signal through the central adaptor MyD88, which assembles a Myddosome that recruits the IL-1 receptor-associated kinases IRAK4 and IRAK1. IRAK4 phosphorylates and activates IRAK1, and the kinase module engages the E3 ubiquitin ligase TRAF6. TRAF6-catalyzed synthesis of lysine-63-linked polyubiquitin chains activates downstream kinase complexes that converge on NF-kB and MAP kinase pathways to induce inflammatory cytokines. In specialized endosomal contexts, particularly TLR9 signaling in plasmacytoid dendritic cells and the TLR3 pathway, the cascade activates interferon regulatory factors such as IRF7, the master driver of type I interferon production critical for antiviral immunity. The balance and localization of these signals determine whether the response is predominantly proinflammatory or antiviral. Dysregulated TLR signaling contributes to sepsis, chronic inflammatory disease, and autoimmunity, while TLR agonists and antagonists are being developed as vaccine adjuvants and therapeutics. Mapping this branching cascade requires reagents that span receptors, adaptors, kinases, and transcription factors. This sampler pack brings together validated antibodies against TLR4, TLR3, TLR9, MyD88, IRAK1, IRAK4, TRAF6, and IRF7 for studying innate immune recognition and TLR signal transduction.
![Anti-IRAK1 [ARC1009] Monoclonal Antibody (CAB4439)](https://cdn11.bigcommerce.com/s-39x6lpnvxv/images/stencil/1280x1280/products/237936/281207/tlr-innate-immune-signaling-antibody-sampler-pack__27183__57459.1786234167.jpg?c=1&imbypass=on "Anti-IRAK1 [ARC1009] Monoclonal Antibody (CAB4439)")
![Anti-IRAK1 [ARC1009] Monoclonal Antibody (CAB4439)](https://cdn11.bigcommerce.com/s-39x6lpnvxv/images/stencil/100x100/products/237936/281207/tlr-innate-immune-signaling-antibody-sampler-pack__27183__57459.1786234167.jpg?c=1 "Anti-IRAK1 [ARC1009] Monoclonal Antibody (CAB4439)")
![Anti-Notch1 [ARC0285] Monoclonal Antibody (CAB19090)](https://cdn11.bigcommerce.com/s-39x6lpnvxv/images/stencil/590x590/products/237928/281105/notch-signaling-antibody-sampler-pack__02338__49551.1786234108.jpg?c=1 "Anti-Notch1 [ARC0285] Monoclonal Antibody (CAB19090)")
![Anti-JAK1 [ARC0434] Monoclonal Antibody (CAB11963)](https://cdn11.bigcommerce.com/s-39x6lpnvxv/images/stencil/590x590/products/237933/281148/jak-stat-signaling-antibody-sampler-pack__25956__55167.1786234122.jpg?c=1 "Anti-JAK1 [ARC0434] Monoclonal Antibody (CAB11963)")
![Anti-TNF-alpha [ARC52538] Monoclonal Antibody (CAB21265)](https://cdn11.bigcommerce.com/s-39x6lpnvxv/images/stencil/590x590/products/237940/281205/cytokine-signaling-tnfil-antibody-sampler-pack__44617__66014.1786234166.jpg?c=1 "Anti-TNF-alpha [ARC52538] Monoclonal Antibody (CAB21265)")
![Anti-IL6 [ARC5093-01] Monoclonal Antibody (CAB22222)](https://cdn11.bigcommerce.com/s-39x6lpnvxv/images/stencil/590x590/products/237940/281210/cytokine-signaling-tnfil-antibody-sampler-pack__65395__83172.1786234168.jpg?c=1 "Anti-IL6 [ARC5093-01] Monoclonal Antibody (CAB22222)")