B cell depletion in Mtb-infected AID^−/−µS^−/− mice allows for improved control of bacterial burdens in the spleen, but not in the lung.

<p>C57BL/6 (closed symbols) and AID^−/−µS^−/− (open symbols) mice were infected as for <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0061681#pone-0061681-g001" target="_blank">Figure 1</a> and then treated every other week starting either day 0 or day 30 with an isotype control antibody (circles) or with an anti-mouse CD20 antibody (αCD20, squares) and (A) flow cytometry was used to determine depletion of CD19⁺CD3⁻ cells at day 30 (depletion was maintained through day 60 - not shown). (B) The bacterial burden was determined by plating the lung and spleen on agar and counting viable colony forming units. (C) Radiation bone marrow chimeras were made with bone marrow from C57BL/6 (closed circles) AID^−/−µS^−/− (open circles) or a mixture of the two (half filled circles) and then infected as for <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0061681#pone-0061681-g001" target="_blank">Figure 1</a> and the bacterial burden in the spleen measured. (D) C57BL/6 (closed symbols) and AID^−/−µS^−/− (open symbols) mice were infected as for <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0061681#pone-0061681-g001" target="_blank">Figure 1</a> and then treated every three days starting at day 15 with normal mouse serum (triangles) or were left untreated (circles). Bacterial burden was assessed at day 60. Data from two separate experiments showing the same results independently have been combined in A–D (<i>n</i> = 8–10 mice per group). **, p<0.01; ***, <i>p</i><0.001 by ANOVA with Tukey’s multiple comparisons post-test.