Determination of an age-specific T-cell subset reference interval by flow cytometry for the Maltese population.

Abstract

Peripheral blood lymphocyte subsets in healthy individuals vary according to age, and the extent of such variation tends to differ according to race (Shearer et al., 2003). Currently, the reference values applied for Maltese patients are those established by centres abroad. Due to any discrepancies in reference ranges because of racial differences (Jentsch- Ullrich, Koenigsmann, Mohren, & Franke, 2005), aT-cell subset reference interval should be established based on the Maltese population, in order to allow a more accurate evaluation of the patient's immune system. The aim of this study is to establish an age-specific T-cell subset reference interval specifically for the Maltese population. This study has analysed T- cell lymphocyte subsets of a representative number of healthy individuals within 5 strata of different age groups. The samples were analysed by a 4 - colour dual laser FACSCalibur flow cytometer (BD Immunocytometry Systems, San Jose, CA), and staining was carried out using a combination of fluorochrome conjugated monoclonal antibodies. The distribution of results was assessed using descriptive statistics and a comparison of means was performed. Finally, an age-specific reference interval was defined. The study shows that an age- and region-specific reference interval should be applied to the Maltese population when evaluating a person's immune status.