TMEM175-deficient lysosomes from mouse macrophages and human cells are hypo-acidified. (A and B) The lysosomal pH of cultured extracted peritoneal mouse macrophages (A) from WT and TMEM175 KO mice, as well as cultured WT and TMEM175 KO HEK293T human cells (B). Macrophages were cultured from adult mice from the K1 and K3 TMEM175 KO lines. For HEK293T cells (B), two independent KO lines (KO/5 and KO/19) with different deletions were tested (see Fig. S5 for sequences deleted in each line). The numbers in parenthesis are the number of cells in each condition. P values are from unpaired two-tailed t test, where * is P < 0.05 and ***** is P < 10⁻⁷. Error bars are SEM.