Role of Synovial Immune Responses in Stifle Synovitis 105In conclusion, both antigen-specific and
innate immune responses within the stifle syn-
ovium overlying the cruciate ligament complex
appear important to the development of syn-
ovitis and joint degeneration over time. In this
regard, the overlying synovium has an impor-
tant barrier function (Bozynskiet al. 2015) that
is poorly understood. A functional connection
between ligament loading and disturbances to
ligament homeostasis, that includes the devel-
opment of inflammation in the synovium over-
lying the cruciate ligaments, may occur through
macrophages, since macrophages respond to
specific motifs in mechanically damaged col-
lagen. T lymphocytes and macrophages likely
represent important therapeutic targets in dogs
with CR. If disturbances to ligament homeosta-
sis, matrix remodeling and the development
of synovitis can be successfully managed with
medical therapy, then such a treatment may
block the development of CR and associated
joint instability in affected dogs.
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