Laboratory-Based Studies
Blood Collection Cassette for Serum Transferrin Receptor Analysis
(Contact: Lisa Zeng; In Progress)
Assessment of IDA in population studies requires reliable and accurate measures of iron status. Serum transferrin receptor (sTfR) is a sensitive and specific functional measure of iron deficiency that quantifies tissue iron availability. Although the sTfR assay requires a very small volume of capillary blood, a number of practical issues limit its utility in remote or underdeveloped regions, where problems of iron deficiency are most prevalent.
In the remote or underdeveloped regions, there is often limited access to adequately equipped laboratories with trained technicians for reliable laboratory testing, adequate facilities are not always available to store frozen serum samples and there are often problems keeping samples cool during transport from the field site to the laboratory. If local laboratories are not available, shipping of samples to a central laboratory under controlled temperature is often costly and difficult to manage. In such cases, using a dried spot technique is most appropriate.
As one of Dr. Zlotkins research activities, with funding from the Centers for Disease Control and Prevention (CDC), we are expanding the application of the sTfR dried blood spot technique to true field conditions, such as in a tropical setting where room temperature and humidity is extremely high.
Our long-term objective will be to facilitate the collection of blood for the assessment of iron deficiency. Avoiding the need to store frozen samples overcomes many of the logistical problems associated with using traditional methods in remote settings.
Specifically, we will refine this novel blood collection cassette that uses dried blood spot methodology to measure serum transferrin receptor to assess iron status. We will
further test the viability of this blood collection cassette in a field setting in Ghana, West Africa.
Our pilot study showed, using a new design of cassette that:
- Serum dried spot sample sTfR, irrespective of storage conditions (4*C or room temperature (18-26*C)) was highly linear correlated with the traditional frozen serum method.
- The mean percentage recovery rate for serum dried spot sample sTfR value was around 86%. No significant difference between two storage temperatures (4*C and room temperature) in terms of sTfR value and percentage recovery rate was found.
- No significant sTfR immunoactivity loss for serum dried spot samples for at least 28 days after sampling when compared to frozen serum samples was found.
- Measurement agreement analysis revealed: Serum dried spot samples stored under 4*C and room temperature (18-26*C) agree sufficiently with traditional frozen serum samples on sTfR value. The new method can be used to replace the gold standard frozen serum method.
