Ecology of iron deficiency and immune function in Kenya
This research, conducted in collaboration with Dr. Bettina Shell-Duncan (U Washington), explores iron-deficiency as a potentially adaptive response to infectious disease among Rendille children in the Marsabit District of northern Kenya. This group of formerly nomadic pastoralists is becoming increasingly settled around towns and mission stations, and children endure relatively high rates of anemia, undernutrition, and infectious disease.
Like fever, the iron-withholding response has been identified as a potentially adaptive response to infection by limiting the bioavailability of iron for invading microbes. However, iron deficiency is recognized as the most common micronutrient deficiency in the world, and supplementation is often recommended, particularly for children and women of childbearing age.
By developing a blood spot method for measuring serum transferrin receptor, and using this measure in conjunction with other markers of infection (CRP), iron status/anemia (zinc protoporphyrin:heme ratio, hemoglobin), and immune function (EBV antibody level), we hope to define optimal iron status, and to explore the relationships among iron, anemia, immune function, and infectious disease risk.
Shell-Duncan, B. and T.W. McDade (2004). Use of combined measures from capillary blood to assess iron deficiency in rural Kenyan children. Journal of Nutrition 134: 384-387.
McDade, T.W. and B. Shell-Duncan (2002). Whole blood collected on filter paper provides a minimally-invasive method for assessing human transferrin receptor. Journal of Nutrition 132: 3760-3763.