and cryopreserved in 30% sucrose for 24 hours. Tissues were embedded in OCT
compound (Fisher HealthCare) and stored at −80°C. Tissues were
sectioned at 5μm thickness with a cryostat. The sections were incubated
with monoclonal anti-CD68 (1:100; Bio-Rad, Cat# MCA1957), anti-CD3 (1:100;
Invitrogen, Cat# ma5–14524) or anti-TCRβ (1:100; eBioscience, Cat#
16-5961-82) overnight at 4°C and corresponding Biotin-SP-conjugated
secondary antibodies (1:200; Jackson ImmunoResearch Laboratories) for 40 minutes
and Alexa Fluor 594 streptavidin (1:200; Molecular Probes, Cat# S11227) for 30
minutes at room temperature. Sections were mounted with Vectashield mounting
media with Dapi (Vector Laboratories, Cat# H-1200). 60× images were
captured with Keyence BZ-X710fluorescent microscope. 40× tile images were
also captured and XY-stitching was performed to recreate the full image of the
aortic tissue for quantification. Cell counting was performed with ImageJ with
the Cell Counter plugin and normalized to the measurement of outer medial
circumference.