Table 3.
Distribution of gold HDL at 37°Ca
| Percent distribution of gold HDL
|
|||
|---|---|---|---|
| Time at 37°C (min) | Microvilli + cell surface | Caveolae + small vesicles | MVB |
| A. WI38[SR-BI] | |||
| 5 | 99.8 | 0.2 | 0 |
| 15 | 96.9 | 3.1 | 0 |
| 60 | 91.9 | 0.3 | 7.8 |
| B. Y1-BS1 | |||
| 5 | 99 | 1 | 0 |
| 15 | 94.6 | 1.5 | 3.9 |
| 60 | 73.4 | 0.6 | 26 |
Cells were incubated with 10 μg/ml gold HDL for the indicated times, washed, fixed, subjected to gold enhancement, and processed for electron microscopy. Total number of gold particles counted for the 5-, 15-, and 60-min time points were, respectively: WI38[SR-BI] 518, 1040, 1137; Y1-BS1 393, 613, 1445. The distributions of gold particles between microvillar extensions and undifferentiated cell surface membrane regions for the three time points were, respectively (in percent of total): WI38[SR-BI] (5 min) 66.4%, 33.4%; (15 min) 66.1%, 30.8%; 60 min) 77.1%, 14.8%; Y1-BS1 (5 min) 89%, 10%; (15 min) 88.7%, 5.9% (60 min) 57.9%, 15.5%. Micrographs were taken at 12,000× and enlarged 3× upon printing. MVB, multivesicular body