Effect of Aging on Auto-Antibodies to Wounded Tissues

Wound healing succeeds tissue destruction. We hypothesized that antibodies might bind to wounded tissues, which would facilitate the engulfment of damaged tissues by macrophages. We detected the autoantibodies in sera of different ages of mice, which bind to wounded tissues. We detected IgG1 binding to wounded tissues by using FITClabeled anti-IgG1 in C57BL/6 mice. These bands were highest in 4 months old C57BL/6 mice. The sera taken from 2 months and 20 months old mice also bound to wounded tissues, although the bands were weaker than those of 4 months old mice. We also examined the autoreactive IgM binding to wounded tissues. We could detect relatively strong bands even in 2 M old mice. The pattern of these bands was changed by advancing age. Intensity of IgM bands was not decreased by advancing age. The splenectomy reduced the intensity of IgG1 bands especially in 4 months old mice. Although we observed the slight delay of wound repair by splenectomy in 2 M and 20 M old mice, we observed that wound repair was strongly delayed in 4 M old mice. Serum from any age of mice enhanced the macrophage phagocytosis by opsonization. Serum taken from splenectomized mice decreased the opsonizing capacity only at 4 M.