The mechanisms involved in the pathogenesis of melioidosis, caused by the 
intracellular bacterium Burkholderia pseudomallei, are unclear. C57BL/6 mice are 
resistant to infection, while BALB/c mice are highly susceptible. Previous 
studies have demonstrated that peritoneal exudate cell preparations enriched for 
macrophages are capable of effectively eliminating intracellular pathogens. In 
this study we present evidence showing that interaction of macrophages with 
lymphocytes is necessary for efficient anti-B. pseudomallei activity.