This invention discloses the use of an E-selectin antagonist in methods and compositionsfor treating or preventing immunocompromised conditions resulting from medicaltreatment. The present invention is particular useful for prophylaxis and/ortreatment of hematopoietic disorders including neutropenia, agranulocytosis,anemia and thrombocytopenia in individuals receiving or proposed to receivetreatments that target rapidly dividing cells or that disrupt the cell cycleor cell division.