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Updated: May 25, 2026
10:11
Immunohistochemical Staining of B7-H1 (PD-L1) on Paraffin-embedded Slides of Pancreatic Adenocarcinoma Tissue
Published on: January 3, 2013
The PD-1/PD-L1 pathway in human pathology.
M Saresella1, V Rainone, N M Al-Daghri
1Don C Gnocchi Foundation, ONLUS, Milan, Italy.
Current Molecular Medicine
|February 4, 2012
Summary
Programmed death 1 (PD-1) and its ligands are crucial for regulating T-cell activation and immune tolerance. This review explores their roles in immune-mediated diseases.
Area of Science:
- Immunology
- Molecular Biology
- Cellular Biology
Background:
- T-cell activation relies on signals from T-cell receptors and accessory receptors.
- Costimulatory and inhibitory receptors modulate T-cell responses, influencing tolerance and immunopathology.
Purpose of the Study:
- To review the immunoregulatory functions of Programmed death 1 (PD-1) and its ligands (PD-L1, PD-L2).
- To examine the involvement of the PD-1 pathway in immune-mediated diseases.
Main Methods:
- Literature review of current research on PD-1 signaling.
- Analysis of studies investigating PD-1's role in T-cell activation and immune responses.
Main Results:
- PD-1 and its ligands deliver critical inhibitory signals.
- These interactions play a vital role in T-cell activation, immune tolerance, and preventing tissue damage.
Conclusions:
- The PD-1 pathway is a key regulator of immune homeostasis.
- Dysregulation of PD-1 signaling is implicated in various immune-mediated diseases.
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