Table I.

Quantitation of total and bundled F-actin in T cells following alterations to LFA-1

TreatmentIntegralMaximum Pixel
Fluorescence (×103)Cell numbera (%)Fluorescence (×103)Cell numbera (%)
PLL1105.9 ± 52.214.1 ± 2.82241.7 ± 151.210.0 ± 1.5
PLL/MgEGTA1403.4 ± 193.819.9 ± 6.6 (5.8)2525.7 ± 185.46.7 ± 1.6
PLL/MgEGTA/dICAM-11316.8 ± 142.416.7 ± 4.5 (2.6)2405.3 ± 107.37.3 ± 0.6
mAb G25.2 (anti-LFA-1)1499 ± 17.3b37.1 ± 0.3 (23.0)3471.7 ± 87.5b26.7 ± 2.2 (17)
mAb G25.2/MgEGTA2011.3 ± 96.2c63.3 ± 3.3 (52.9)4674.3 ± 120.1c49.7 ± 3.6 (40)
mAb G25.2/MgEGTA/dICAM-12065.9 ± 23.6c67.0 ± 1.8 (47.2)4963.0 ± 50.2c51.0 ± 4.1 (41)
  • a Percentage of total T cells that have fluorescence levels greater than that defined by the gate set to include the majority of the PLL control T cell population. Numbers in parentheses indicate the percentage of T cells expressing increases in F-actin greater than the total PLL-adhering T cell population.

  • b F-actin levels in all mAb G25.2-treated T cells are significantly greater than PLL treated cells (p < 0.001).

  • c Mg2+EGTA/G25.2-treated T cells have significantly greater amounts of F-actin than T cells tethered on mAb G25.2 alone (p < 0.001).