Expression of Endoplasmic Reticulum-Mediated Stress Proteins in FK506-Treated T-Lymphocytes

Area of Science:

• Immunology
• Cell Biology
• Molecular Biology

Background:

• FK506 is known to affect T-lymphocytes.
• Endoplasmic reticulum (ER) stress is implicated in apoptosis.
• Investigated FK506's impact on ER-mediated stress proteins in Jurkat cells.

Purpose of the Study:

• To investigate FK506-induced apoptotic endoplasmic reticulum (ER)-mediated stress protein expression.
• To examine the dose- and time-dependent effects of FK506 on Jurkat T-lymphocyte viability and apoptosis.

Main Methods:

• FK506 treatment of Jurkat T-lymphocytes.
• Assessed apoptosis via DAPI staining and cell viability assays.
• Analyzed ER stress protein expression (Grp78/BiP, Grp94, PERK, p-PERK, CHOP/GADD153, Bak, iNOS) using Western blotting.
• Flow cytometry used for reactive oxygen species detection (DAF-DA, DCF-DA).

Main Results:

• FK506 induced apoptosis and decreased cell viability in a dose- and time-dependent manner.
• Increased expression of Grp78/BiP, Grp94, phospho-PERK, CHOP/GADD153, and iNOS observed post-FK506 treatment.
• Phospho-PERK activation peaked at 36 hours, while CHOP/GADD153 increased at 48 hours.

Conclusions:

• FK506 induces apoptosis in Jurkat cells via ER-mediated stress pathways.
• FK506's effects on apoptosis and cell viability are dose- and time-dependent.
• Activation of specific ER stress proteins correlates with FK506-induced apoptosis.