ABCG2 and tuberculosis: By histochemical staining after the ZN method, which detects acid-fast mycobacteria (which by definition have undamaged cell walls), and by immunofluorescent staining with antibodies reacting with the major mycobacterial cell wall component glycolipid lipoarabinomannan (LAM) or with Ag38 (a glycolipoprotein involved in the transport of inorganic phosphate by the ABC transporter of the Mtb cell wall and encoded by the pstS-1 gene [39]), we determined cells with Mtb in ex vivo cultures of cells obtained from the lung tissue samples of all investigated TB patients.