Table 1.

Percent of uptake and intracellular growth of M. avium 109 and clones in U937 and monocyte-derived macrophages

Clone	Uptake U937 (1 h), %	Uptake hM0 (1 h), %	Growth in Mo U937 (4-day)
WT bacterium	14 ± 0.4	16 ± 0.8	log 1.8
8H8	2 ± 0.1	2.2 ± 0.1	log 0.1
9B9	2 ± 0.3	2.1 ± 0.4	log 2.7
9C3	1 ± 0.2	1.0 ± 0.3	log 2.8
9E6	3 ± 0.6	2.8 ± 0.2	log 2.5
10A11	1 ± 0.3	1.3 ± 0.1	log 2.8
10B9	3 ± 0.4	3.4 ± 0.3	log 1.3
Complemented 9C3	13.8 ± 0.5	14.9 ± 0.9	log 1.8
Complemented 8H8	1.6 ± 0.3	1.5 ± 0.4	log 0.5

Percent of uptake was calculated as the ratio between the number of bacteria added to the tissue culture well and the number of bacteria recovered from the lysed macrophages. Average cfu of the bacterium strains: 2.1 ± 0.8 × 10⁶. The assays were repeated at least 3 times, and the results represent the mean ± SD. All of the clones shown in the table had statistically significant decrease of uptake when compared with the wild-type strain.