The monoclonal antibody TLR3.7 recognizes the 116 kDa human Toll-like receptor 3 (TLR3, CD283).
Toll-like receptors (TLRs) are highly conserved from Drosophila to humans and share structural and
functional similarities. TLRs constitute of a family of pattern recognition receptors (PRRs) that mediate
cellular responses to a large variety of pathogens (viruses, bacteria, and parasites) by specific
recognition of so-called ‘pathogen-associated molecular patterns’. Activation of TLRs, a family of at
least 11 different members that function either as homo- or heterodimers, leads to activation of NFκBdependent
and IFN-regulatory factor-dependent signaling pathways. TLRs have a central role in
innate immunity and are also required for the development of an adaptive immune response. TLRs
are expressed by various cells of the immune system, such as macrophages and dendritic cells. TLRs
are class I receptors, with a single α-helix that spans the cell membrane. They recognize and respond
to molecules derived from bacterial, viral and fungal pathogens, such as lipopolysaccharide (LPS)
from the outer membrane of Gram negative bacteria, peptidoglycan fragments from bacterial cell walls
and single-stranded and double-stranded RNA from viruses.
Some forms of RNA and DNA from pathogens exhibit immutable features that distinguish them from
nucleic acids of higher organisms. For example, dsRNA, is a common intermediate of viral replication
and a potent indicator of infection. Toll-like receptor 3 (TLR3) recognizes viral double-stranded RNA
and its synthetic analog polyriboinosinic:polyribocytidylic acid (poly(I:C)). TLR3 is normally located in
acidic endosomes where its luminal ectodomain (ECD) encounters dsRNA and induces type I
interferon (IFN), inflammatory cytokine/chemokine production and dendritic cell (DC) maturation via
the adaptor protein TICAM-1 (also called TRIF). Based on the different subcellular localization of
cytosolic RNA receptors and TLR3, these receptors seem to play distinct roles in anti-viral immune
Flow cytometry, Frozen sections, Functional studies, Immuno fluorescence, Immuno precipitation, Paraffin sections
F: dried sections, fixed with 4% paraformaldehyde and subsequently washed in PBS and MQ. Sections were quenched with 0.3%H2O2 in methanol and washed in PBS. Sections were permeabilized with 0.4% triton-X100 in PBS. Pretreated slides were blocked with 1% horse serum for 20’ and incubated o/n with antibody (Ref.5).
FC: cells were incubated with 1 μg antibody together with 10 μg human IgG for 30’at 4°C in PBS/0,5% BSA (Ref.3).
FS: 7.5*104 MRC5 cells were pre-treated with 10-20μg/ml for 1-24h at 37°C. Monoclonal antibody TLR3.7 inhibits dsRNA-induces IFN-beta production (Ref.1).
IF: Cytospins of monocyte-derived iDCs were fixed for 30’ with 3% formaldehyde in PBS, permeabilized with PBS/1%BSA/0.5%saponin. After PBS wash slides were incubated for 1h at RT with 20ug/ml antibody in PBS/1%BSA (Ref.3).
P: Formalin fixed, paraffin embedded sections were deparaffinized with xylene, followed by washes in 95% and 70% EtOH. Sections were washed with water and permeabilized with 0.4% triton-X100 in PBS. Pretreated slides were blocked with 1% horse serum for 20’ and incubated o/n with antibody (Ref.5).
W: Total cellular protein was loaded on 7.5% SDS-PAGE and blotted on PDVF. Blots were incubated with 2μg/ml antibody o/n at 4°C (Ref.6).
Dilutions to be used depend on detection system applied. It is recommended that users test the reagent and determine their own optimal dilutions. The typical starting working dilution is 1:50.
Monocytes, granulocytes, lymphocytes, human fibroblast, MRC-5 & FS-4 cells