Methotrexate Accumulation In Patient Guts: Target Intestinal Mucosa Variation By Disease State Overview This study investigates the accumulation of intracellular methotrexate polyglutamates (MTX-PGs) in different cell types to identify a more accurate biomarker for methotrexate (MTX) therapy in Crohn’s disease (CD) patients. MTX-PG3 concentrations in red blood cells (RBCs) are known to