TY - JOUR T1 - Does beta2 adrenoceptor (ADRβ2) density vary in circulating lymphyocytes compared with monocytes? JF - European Respiratory Journal JO - Eur Respir J VL - 38 IS - Suppl 55 SP - p3811 AU - Li Ping Chung AU - Svetlana Baltic AU - Grant Waterer AU - Philip Thompson Y1 - 2011/09/01 UR - http://erj.ersjournals.com/content/38/Suppl_55/p3811.abstract N2 - Circulating lymphocytes are increasingly used as a surrogate cell type to reflect changes in ADRβ2 density elsewhere in the body, particularly the respiratory system. However, ADRβ2 density is non-uniform among lymphocyte subsets and potentially varies between individuals.Aim: To assess the extent of variability in ADRβ2 density on human peripheral blood mononuclear cells (PBMC) including lymphocytes and monocytes.Method: PBMC were isolated from 10 healthy subjects by density gradient centrifugation with Ficoll-Paque. Cell surface & total ADRβ2 of lymphocytes (CD14+) and monocytes (CD3+) measured using FACS. Geometric mean fluorescence (GMF) was used as the indices for ADRβ2 density per cell.Result: Surface ADRβ2 - GMF increased by 3.54 and 4.62 folds over negative controls for lymphocytes and monocytes respectively (p=0.16). However, distribution of GMF between samples suggests greater variability in ADRβ2 density in lymphocytes vs monocytes (p=0.06). Proportion of ADRβ2-positive cells was higher in monocytes vs lymphocytes (71.9% vs 36.7, p=0.02). Total ADRβ2 – GMF increased by 12.4 and 9.61 folds for lymphocytes and monocytes respectively (p>0.05). Proportion of ADRβ2-positive cells were similar between samples (lymphocytes 80%, monocytes 86%, p>0.05) but greater variability was observed for lymphocytes (range 27–99%) vs monocytes (range 66–100%).Conclusions: Despite similarities in surface and total ADRβ2 density, lymphocytes display greater inter-subject variability compared with monocytes. This has implication in experimental designs & interpretation of changes in ADRβ2 density in studies using human PBMC as an alternative to primary cells from organ of interest. ER -