The influence of processing factors and non-atopy-related maternal and neonate characteristics on yield and cytokine responses of cord blood mononuclear cells
Article first published online: 9 DEC 2007
Clinical & Experimental Allergy
Volume 38, Issue 2, pages 298–304, February 2008
How to Cite
Sullivan Dillie, K. T., Tisler, C. J., DaSilva, D. F., Pappas, T. E., Roberg, K. A., Carlson-Dakes, K. T., Evans, M. D., Rosenthal, L. A., Gangnon, R. E., Gern, J. E. and Lemanske, R. F. (2008), The influence of processing factors and non-atopy-related maternal and neonate characteristics on yield and cytokine responses of cord blood mononuclear cells. Clinical & Experimental Allergy, 38: 298–304. doi: 10.1111/j.1365-2222.2007.02891.x
- Issue published online: 9 DEC 2007
- Article first published online: 9 DEC 2007
- Submitted 14 December 2006; revised 19 September 2007; accepted 21 September 2007
- cord blood;
- environmental exposures;
- mononuclear cells;
- season of year
Rationale Several studies have evaluated the associations between cord blood cellular responses and atopic diseases in children, but the results of these studies are inconsistent. Variations in blood processing factors and maternal and infant characteristics are typically not accounted for and may contribute to these inconsistencies.
Methods Cord blood samples were obtained from 287 subjects participating in the Childhood Origins of ASThma project, a prospective study of children at high risk for the development of asthma/allergies. Mononuclear cells were stimulated with phytohaemagglutinin (PHA), phorbal myristate acetate/ionomycin or a suspension of killed staphylococcus, and IFN-γ, IL-10 and IL-13 were quantitated by ELISA. Cell yields and cytokine production were related to processing factors and maternal and infant characteristics.
Results The strongest relationships between independent variables and cell yield or cytokine responses occurred with the season of birth. The highest median cell yields were seen in fall, and the lowest in summer (difference of 47%, P=0.0027). Furthermore, PHA-induced IL-5 and IL-13 responses were approximately 50% higher in spring and summer than in fall or winter (P<0.0001). Clots in the cord blood samples were associated with a reduced median cell yield (42% reduction, P<0.0001), and an increased PHA-induced IL-10 secretion (27% increase, P=0.004).
Conclusions These data suggest that season of collection, and to a lesser extent clotting in samples, affect cord blood mononuclear cell yield and cytokine responses. Careful documentation and analysis of processing and environmental variables are important in understanding biological relationships with cytokine responses, and also lead to greater comparability among studies using these techniques.