TABLE 4.

In vitro survival of BCG and DPP in murine peritoneal macrophages from iNOS knockout mice, with and without IFN-γ plus LPS^a

Bacterial strain and treatment	Colony countb				Pc
	Mean		SE
	24 h	5 days	24 h	5 days
BCG
None	1,238	2,847	304.9	688.2	0.1800
IFN-γ + LPS	987	287	286.4	58.4	0.0459
DPP
None	2,154	6,573	338.59	823	0.0003
IFN-γ + LPS	1,093	2,557	327.15	684.8	0.033

^aThioglycolate (3%) was injected into the peritoneal cavities of iNOS^−/− mice. Four days after injection, animals were anesthetized with Isoflurane. Peritoneal cavities were washed with ice-cold RPMI to recover peritoneal macrophages. Peritoneal macrophages were infected with BCG or DPP at an MOI of 10:1. At 2 h after infection, unphagocytosed organisms were removed. BCG- or DPP-infected macrophages were maintained in RPMI containing 10% fetal bovine serum or in RPMI containing 10% fetal bovine serum, IFN-γ (100 U/ml), and LPS (1 μg/ml).

^bIntracellular colony counts were determined by plating lysed cultures on Middlebrook 7H11. Results are averages from three experiments done in triplicate.

^cCalculated with the Statview program.