title: Distribution of Toll-like receptor 1 and Toll-like receptor 2 in human lymphoid tissue.
abstract: To determine how distinct receptors of the immune system can contribute to innate immunity, we investigated the pattern of Toll-like receptor 1 (TLR1) and TLR2 expression in human lymphoid tissue. We found that TLR1 and TLR2 were co-expressed on cells of the innate immune system, including macrophages and dendritic cells. In addition, TLR1 and TLR2 were expressed in mucosa-associated lymphoid tissue on tonsillar crypt epithelium. Of the lymphoid tissue examined, spleen expressed the highest levels of TLR2. Although TLR1- and TLR2-positive cells were in close proximity to T lymphocytes in vivo, lymphocytes themselves were devoid of TLR1 and TLR2 expression. The co-expression of TLR1 and TLR2 on myeloid cells in lymphoid tissue provides the host with the ability to respond to a variety of microbial ligands at sites conducive to the generation of an immune response.
authors.affiliation: Division of Dermatology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA,
authors.forename: Maria-Teresa
authors.initials: MT
authors.lastname: Ochoa
authors.forename: Annaliza J
authors.initials: AJ
authors.lastname: Legaspi
authors.forename: Zena
authors.initials: Z
authors.lastname: Hatziris
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Godowski
authors.forename: Robert L
authors.initials: RL
authors.lastname: Modlin
authors.forename: Peter A
authors.initials: PA
authors.lastname: Sieling
mesh_terms: D003713:Dendritic Cells / Q000276:immunology; D029721:Drosophila Proteins; D004847:Epithelial Cells / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques; D008221:Lymphoid Tissue / Q000276:immunology*; D008264:Macrophages / Q000276:immunology; D008562:Membrane Glycoproteins / Q000378:metabolism*; D018613:Microscopy, Confocal; D014066:Palatine Tonsil / Q000276:immunology; D011956:Receptors, Cell Surface / Q000378:metabolism*; D013154:Spleen / Q000276:immunology; D051194:Toll-Like Receptor 1; D051195:Toll-Like Receptor 2; D051193:Toll-Like Receptors
chemical_list: D029721:Drosophila Proteins; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; C495342:TLR2 protein, human; D051194:Toll-Like Receptor 1; D051195:Toll-Like Receptor 2; D051193:Toll-Like Receptors