Figure 1.

Overproduction of prostaglandin (PG)E₂ elevates phosphatase and tensin homolog deleted on chromosome 10 (PTEN) activity and diminishes pAKT levels in bone marrow transplantation (BMT) alveolar macrophages (AMs). Mice were given syngeneic BMT and harvested 5 to 6 weeks after transplant. AMs were isolated by bronchoalveolar lavage as described in Materials and Methods from BMT and nontransplanted control mice. (A) PTEN protein was immunoprecipitated from whole-cell lysates of AMs cultured at 5 × 10⁵ per well in the presence of 5 μM indomethacin or 0.05% vehicle control overnight. PTEN phosphatase activity was determined as described in Materials and Methods. Results are represented as PTEN phosphatase activity relative to the untreated control group (*P < 0.05; n = 3–4 per group combined from two experiments). (B) AMs were pretreated with 5 μM indomethacin for 2 hours or 100 nM PGE₂ for 15 minutes at 37°C. AMs were then stimulated with IgG–sheep red blood cells (SRBCs) (1:10 ratio) for 15 minutes at 37°C. After IgG-SRBC stimulation, AMs were prepared for Western blot analysis as described in Materials and Methods. Relative band densitometry data are indicated under each lane. Data shown are representative of two experiments.