After 2 days in vitro, 22 uM cytosine b D arabino furanoside was added to inhibit the growth of non neuron cells. After 24 hours, the med ium was removed and replaced with a 1,1 mixture of glial conditioned medium and mean MEM. This Inhibitors,Modulators,Libraries medium was 50% exchanged with fresh medium after 5 days. The cultures contained about 97% neurons and 3% astrocytes as assessed by immunostaining for the neuron marker MAP2 and the astrocyte marker GFAP. Microglia and microglia neuron co cultures Cortices were dissected from 1 day old mice and disso ciated by mincing followed by incubation in papain and DNase for 10 minutes at 37 C. After centrifugation for 5 minutes at 500 g, the cells were re suspended and triturated with a fire polished Pasteur pipette into Eagles minimal essential medium containing 5 mM glucose and supplemented with 10% fetal bovine serum and 2 mM glutamine.

Cells were plated on 24 well plates or glass coverslips at a density of 2 �� 105 cells per well, or in 75 cm2 flasks at a density of 5 �� 106 cells per flask, and maintained in a 37 C in a 5% CO2 incubator. The med ium was changed at 3 Inhibitors,Modulators,Libraries days in vitro and once per week thereafter. These cultures contained both astrocytes and microglia. Inhibitors,Modulators,Libraries Microglia were isolated from these cultures at age 2 to 3 weeks in vitro by shaking, and collecting the floating cells. The cells were re plated at a density of 5 �� 105 cells per well in 24 well plates for microglial monocultures, or at the density of 5 �� 104 cells per well on top of 6 day in vitro neuron cultures in 24 well plates for microglia neuron co cultures.

The purity of the re plated microglial monocultures was 99%, and the microglia neuron co cultures contained about 7% microglia, 90% neurons, and 3% Inhibitors,Modulators,Libraries astrocytes as assessed by immunostaining for the microglial marker Iba 1, the neuron marker MAP2 and the astrocyte marker GFAP. Preparation of Ab For in vitro use, 1 mM stock solutions of Ab peptides were Inhibitors,Modulators,Libraries diluted to 250 uM with MEM and incubated for 1 hour at 37 C to produce a mixture of Ab monomers and oligomers. For in vivo use Ab peptides were diluted to 1 mg ml with normal saline. The solution was prepared within one hour of use and kept at room temperature in order to maintain the peptides in oligomeric form. Cell culture treatments Neuron monocultures and microglia neuron co cultures were used at neuron day 7 in vitro. Microglial cultures were used at day 2 3 after re plating.

Cultures were incubated with 5 uM of Ab or 5 uM of rAb alone, or with inhibitors of PARP activation or NF B activation for the desig nated intervals. In some experiments, 5 uM of carboxy fluorescein labeled amyloid b1 42 was used to detect microglial selleck compound phagocytosis of Ab fibrils. All com pounds were dissolved in MEM or GCM MEM mixture, and these solutions were used alone for control conditions.