Table 1.

 T cell/DC contact rates in nine imaging experiments

Experiment number

T cell/DC contacts

Observation period, min:sec

T cell contacts per hour

Fraction of labeled T cells

Scanning rate (contacts/hour)

1

17

52:04

19.6

0.0039

5,026

2

29

52:05

33.5

0.0036

9,294

3

26

52:36

29.7

0.0068

4,368

4

15

52:47

17.1

0.0048

3,562

5

22

56:02

23.6

0.0058

4,069

6

7

25:20

16.5

0.0058

2,845

7

13

30:14

25.8

0.0058

4,448

8

6

17:47

20.3

0.0084

2,416

9

32

52:10

36.7

0.0065

5,646

The scanning rate, defined as the observed number of T cell contacts per hour divided by the fraction of labeled T cells, was 4,630 ± 673 contacts per hour.