Table 1.
Proliferation assays with heterozygous and homozygous N-CAM knockout astrocytes
Reagent | Concentration | Heterozygous N-CAM knockout cells (−/+)
|
Homozygous N-CAM knockout cells (−/−)
|
---|---|---|---|
[3H]thymidine incorporation, % of control | [3H]thymidine incorporation, % of control | ||
N-CAM | 5 μg/ml | 30 ± 1 | 101 ± 8 |
N-CAM | 2 μg/ml | 57 ± 7 | 115 ± 2 |
Ig III | 3 μg/ml | 29 ± 4 | 94 ± 5 |
Ig III | 1 μg/ml | 33 ± 2 | 106 ± 3 |
Astrocytes were obtained from transgenic mice that were heterozygous or homozygous for the disrupted N-CAM allele. N-CAM mRNA and protein was not detected in homozygous astrocytes (13). The amount of [3H]thymidine incorporation is presented as the percent incorporated compared to astrocytes treated with PBS alone. Addition of N-CAM or Ig III recombinant protein decreased the amount of [3H]thymidine incorporation in heterozygous but not homozygous astrocytes. Data are presented as mean ± SD (n = 4 for each condition).