Age-related spontaneous lacrimal keratoconjunctivitis is accompanied by dysfunctional T regulatory cells

Abstract

In both humans and animal models, the development of Sjögren syndrome (SS) and non-SS keratoconjunctivitis sicca (KCS) increases with age. Here, we investigated the ocular surface and lacrimal gland (LG) phenotype of NOD.B10.H2 b mice at 7-14, 45-50, and 96-100 weeks. Aged mice develop increased corneal permeability, CD4 + T-cell infiltration, and conjunctival goblet cell loss. Aged mice have LG atrophy with increased lymphocyte infiltration and inflammatory cytokine levels. An increase in the frequency of CD4 + Foxp3 + T regulatory cells (Tregs) was observed with age in the cervical lymph node (CLN), spleen, and LG. These CD4 + CD25 + cells lose suppressive ability, while maintaining expression of Foxp3 (forkhead box P3) and producing interleukin-17 (IL-17) and interferon-γ 3 (IFN-γ 3). An increase of Foxp3 + IL-17 + or Foxp3 + IFN-γ 3 + cells was observed in the LG and LG-draining CLN. In adoptive transfer experiments, recipients of either purified Tregs or purified T effector cells from aged donors developed lacrimal keratoconjunctivitis, whereas recipients of young Tregs or young T effector cells failed to develop disease. Overall, these results suggest inflammatory cytokine-producing CD4 + Foxp3 + cells participate in the pathogenesis of age-related ocular surface disease.