Folate deficiency and an abnormal lymphocyte deoxyuridine suppression test in monkeys

Cebus albifrons were fed folate-deficient diets in order to assess folate status at the cellular level with the deoxyuridine suppression test. Plasma and red blood cell folates were significantly lower at 2 months, compared to control values. Hematologic signs of megaloblastic anemia occurred after 6 months, with significantly lower hematocrit, hemoglobin and red blood cell number values and increased polymorphonuclear leukocyte lobe counts. Urinary formiminoglutamic acid excretion also was elevated significantly. Whole blood lymphocyte cultures exhibited abnormal deoxyuridine suppression of [3H]-thymidine incorporation into DNA with folate deficiency. Thus this deoxyuridine suppression test can be used in isolated whole blood lymphocytes of these nonhuman primates to document folate deficiency.