Related Experiment Video
Updated: Aug 22, 2026

LPS and ATP-induced Death of PMA-differentiated THP-1 Macrophages and its Validation
Published on: May 3, 2024
Apoptotic effects of LPS on fibroblasts are indirectly mediated through TNFR1
M Alikhani1, Z Alikhani, D T Graves
1Department of Periodontology and Oral Biology, Boston University School of Dental Medicine, MA 02118, USA.
Abstract:
During periods of periodontal attachment loss, one of the most significant cellular changes is a decrease in the number of fibroblasts. We previously demonstrated that LPS induces apoptosis of fibroblastic cells in vivo, largely through TNF-alpha. We conducted in vivo experiments by subcutaneous inoculation of LPS in wild-type, TNFR1-/-R2-/-, TNFR1-/-, and TNFR2-/- mice to identify which TNF receptors are involved and the specific caspase pathway activated. LPS stimulated apoptosis through TNFR1 but not TNFR2, which was accompanied by the induced expression of 12 apoptotic genes. Fluorometric studies demonstrated that LPS in vivo significantly increased caspase-8 and caspase-3 activity, which was also dependent on TNF receptor signaling. By the use of specific caspase inhibitors, caspases-3 and -8 were shown to play an important role in LPS-induced apoptosis in vivo. Thus, LPS acts through TNFR1 to modulate the expression of apoptotic genes and activate caspases-3 and -8.
More Related Videos
08:24Injections of Lipopolysaccharide into Mice to Mimic Entrance of Microbial-derived Products After Intestinal Barrier Breach
Published on: May 2, 2018
07:55A Macrophage Reporter Cell Assay to Examine Toll-Like Receptor-Mediated NF-kB/AP-1 Signaling on Adsorbed Protein Layers on Polymeric Surfaces
Published on: January 7, 2020
Related Concept Videos
NF-κB-dependent Signaling Pathway
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...
The Extrinsic Apoptotic Pathway
TGF - β Signaling Pathway
T Cell Types and Functions
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
Phagocytosis of Apoptotic Cells
Normal cells contain receptors that prevent them from being recognized by phagocytes.
The Intrinsic Apoptotic Pathway