Fig. 2.
AMs are relatively deficient in young but not adult Op/Op mice.
The numbers of AMs in BAL fluid recovered from Op/Op mice and littermate controls (aged 53-210 days) were determined from BAL total cell counts and differential cell staining. (A-B) AMnumbers were similar in adult Op/Op and age-matched littermate controls (n = 6/group; mean age, 149 ± 3.9 days [all mice older than 130 days]; P = .95). (A) Linear regression showed thatAM numbers in Op/Op mice did not change significantly with age (regression line and 95% confidence limits shown; R = 0.166; slope not significantly different from zero; P = .5). (B) A similar analysis showed that AM numbers in littermate control mice decreased significantly with age (slope, −515 ± 241 cells/mouse per day; R = 0.45; P = .046).