FIG 5.

Recovery of live C. muridarum organisms from anorectal swabs for monitoring chlamydial infection in mouse gastrointestinal tract. CBA/J or C57BL/6J mice intravaginally infected with the luciferase-expressing C. muridarum as described in the legends of Fig. 1 and 4 were swabbed from the anorectum on different days after infection as listed along the x axis at the bottom of the figure. The anorectal swabs were assessed for live C. muridarum organisms, expressed as log₁₀ IFUs per swab, shown along the y axis for CBA/1J (a) and C57BL/6J (c) mice. Since groups of mice were sacrificed on different days for making tissue homogenates (see legends of Fig. 3 and 4), the number of mice swabbed from each time point varied from 4 to 31. The number of C. muridarum live organisms recovered from the GI tract tissues harvested at each time was calculated as log₁₀ means and standard deviations and plotted along the same infection course as the swab samples (panels b for CBA/J and d for C57BL/6J). It is clear that the numbers of live organisms detected in the anorectal swabs paralleled with those detected in the GI tract tissue homogenates at the corresponding time points, suggesting that the live-organism recovery from the anorectal swabs can be used for monitoring the GI tract infection.