Background. The co-culture of rat airway myocytes with activated, antigen-specific CD4⁺ T cells induces myocyte proliferation and serves as a model of hyperplasic, T-cell-driven airway smooth muscle remodeling (Ramos-Barbon D. et al. J Clin Invest 2005;115:1580-9).

Aims and objectives. We aimed to translate this model to human cells for drug testing.

Methods. We activated blood memory T cells from house dust mite (HDM)-allergic subjects using D. Pteronyssinus extract on Ficoll-separated mononuclear cells. We co-cultured cell cycle-arrested human airway myocytes (Lonza, France) with the antigen-activated CD4⁺ T cells for 48 hours. The negative growth control was 0.3% fetal bovine serum (FBS) medium. We quantified myocyte proliferation by flow cytometric detection of 5-ethynyl-2 deoxyuridine (EdU) uptake by smooth muscle alpha-actin (?-SMA)⁺ cells.

Results. We present preliminary data from three subjects and independent experiments. D. pteronyssinus stimulation led to CD4⁺ T-cell enrichment from baseline 52.18% (50.51%-60.11%) (median, range) to 84.95% (82.37%-86.01%) CD4⁺ cells (P=0.017). Activated CD4⁺ T-cell co-culture induced EdU uptake by 21.89% (18.15%-29.00%) ?-SMA⁺ cells versus 5.83% (5.11%-6.17%) control (P=0.006).

Conclusions. In HDM-allergic subjects, the activation of blood CD4⁺ memory T cells, and their induction of co-cultured human airway myocyte proliferation, show analogy with the rat. The data support the feasibility of a rat-to-human translation of the antigen-specific, CD4⁺ T-cell-induced myocyte hyperplasia model as a potential drug-testing tool.

Funded by the Instituto de Salud Carlos III (FIS), Spain, & FEDER