Figure 3

Induction of sPLA ₂ -IIA mRNA expression by cytokines and Aβ _1–42 in cultured human astrocytes. Phase contrast micrographs show human astrocytes in control (panel A) and IL-1β-stimulated cultures (panel B) for 24 hours. Human postmortem astrocytes were used for the sPLA2-IIA RNA study. Experiments were performed using cultures derived from 3 neuropathologically confirmed AD cases. A representative gel depicting PCR-amplified fragments for sPLA2-IIA and β-actin is shown in panel C. Gel lanes 1–5 represent the following treatments used in the astrocyte cultures: 1. control; 2. IFNγ (100 ng/ml); 3. Aβ_1–42 (2.5 μM); 4. IL-1β (20 ng/ml); 5. IL-1β and Aβ_1–42. Twenty-four hours after treatment, RNA was extracted from cells, reverse transcribed, and RT-PCR was carried out as described in methods. Panel D shows a bar graph depicting relative units of sPLA₂-IIA expression after normalization with β-actin. Significant differences (*) comparing treatment groups with controls were obtained by one-way ANOVA followed by Tukey multiple comparison post hoc test.