Mitogenic response of lymph nodes and spleen lymphocytes from mice with moderate and severe iron deficiency anemia

Abstract

To define the effects of moderate and severe iron deficiency (Hb: 4–10.4 g/dl) on mitogenic response of lymph nodes (LN) and splenic (S) lymphocytes, C57BL/6 weanling female mice were fed an iron deficient (<5ppm; ID), an iron adequate diet (30 cpm, C) or restricted amounts of the adequate diet (pairfed:PF) for 45–56 days. 3H-thymidine incorporation into DNA was measured in the presence of Con A, PHA and LPS. In both lymphoid organs and with three mitogens tested, iron deficiency significantly reduced blastogenic response (stimulation indices=SI) by 23% to 93%. However, splenic lymphocytes were more affected than lymph nodes. In the spleen, SI positively correlated with Hb and liver iron stores but negatively with spleen weight. Total cpm in response to Con A and LPS were reduced in both S and LN; but those in response to PHA were reduced only in moderately deficient mice. In S but not LN, underfeeding in the overall population of PF mice significantly reduced SI in response to Con A but not PHA or LPS. In ID mice, thymus weight correlated with body weight, (r=0.88), Hb levels (r=0.50) and liver iron stores (r=0.34). While iron deficiency significantly decreased IgG and IgM levels, underfeeding in PF significantly reduced IgA levels and only slightly IgM levels. We conclude that even moderate iron deficiency anemia (11 g/dl<Hb<8 g/dl) impairs mitogenic response in both S and LN.