Figure 4.

Sarcoidosis CD4⁺ T cells with impaired proliferation demonstrate reduced LCK, PI3K, AKT, and mechanistic target of rapamycin (mTOR) protein phosphorylation. Purified systemic CD4⁺ T cells from HCs and patients with sarcoidosis were anti-CD3/CD28 stimulated for 5 minutes. LCK, PI3K, AKT, and mTOR protein activation was assessed in HCs (n = 5) and patients with sarcoidosis (n = 5) with impaired proliferation after TCR stimulation. (A–H) Using specific antibodies, total and phosphorylated LCK (tyrosine 394 [Y394]), PI3K p85 (tyrosine 467/199 [Y467/199]), AKT (threonine 308 [T308]), and mTOR (serine 2,448 [S2448]) at their activation sites were detected after stimulation using Western blot analysis. Error bars show SEM. *P < 0.05, **P < 0.01; NS, not significant (P > 0.05). (I) Representative blots for an HC and patient with sarcoidosis.