TABLE 1.

Parameters of mycobacterial phagocytosis do not differ in I/St and A/Sn lung macrophage cultures^a

Mouse strain	% Nonspecific esterase-positive cells	% Phagocytosisb		Phagocytic numberc
		2:1d	8:1	2:1	8:1
I/St	88 ± 7	27 ± 5	38 ± 7	105 ± 15	181 ± 16
A/Sn	86 ± 8	29 ± 5	46 ± 8	88 ± 13	154 ± 23

^aPlastic-adherent interstitial lung cells were prepared as described in Materials and Methods and plated at 3 × 10⁵/well in 24-well tissue culture plates (Costar-Corning). Single-cell mycobacterial suspensions were added at the indicated MOIs. After 6 h of incubation, the monolayers were fixed with 2% paraformaldehyde and stained with auromine O with Giemsa counterstaining. The basic parameters of phagocytosis were estimated microscopically (magnification, × 1,500). A total of 400 cells in at least 35 fields per point were assessed in two independent experiments. No significant interstrain differences were observed (P > 0.05).

^bPercentage of cells containing at least one mycobacterium.

^cTotal number of mycobacteria per 100 phagocytic cells.

^dMOI.