Figure 1: T-cell development in 6F/6F mice.
From: TCR ITAM multiplicity is required for the generation of follicular helper T-cells
(a) Schematic of αβTCR complexes expressed in 6Y/6Y and 6F/6F mice. Left, TCR complex expressed on αβ T-cells in 6Y/6Y mice containing a total of 10 ITAMs contributed by CD3γ(1) CD3δ(1) CD3ɛ(2) and CD3ζζ(6). Right, TCR complex expressed on αβ T-cells in 6F/6F mice containing a total of four ITAMs contributed by CD3γ(1) CD3δ(1) CD3ɛ(2). In 6F/6F mice, the three ITAMs within each TCRζ chain were inactivated by substitution of both Tyrosine (Y) residues within each ITAM with Phenylalanine (F) residues. (b) Upper panels, representative CD4 versus CD8 staining profiles of thymocytes from H-Y TCR transgenic female 6Y/6Y or 6F/6F mice. Lower panels, number of CD4+CD8+ and CD4−CD8+ (CD8+) thymocytes in H-Y TCR transgenic female 6Y/6Y or 6F/6F mice. N=13 mice of each genotype. (c) Upper panels, representative CD4 versus CD8 staining profiles of thymocytes from AND TCR transgenic 6Y/6Y or 6F/6F mice. Lower panels, number of CD4+CD8+ and CD4+CD8− (CD4+) thymocytes in AND TCR transgenic 6Y/6Y or 6F/6F mice. N=10 mice of each genotype. (d) Vβ surface staining of naïve (CD44lo CD25−) CD3hi CD4-SP splenocytes (top) or naïve (CD44lo) CD3hi CD8-SP splenocytes (bottom). Data are from 10 gender-matched 8-week-old mice of each genotype. (e) Vα surface staining of naïve (CD44lo CD25−) CD3hi CD4-SP splenocytes (left) or naive (CD44lo) CD3hi CD8-SP splenocytes (right) from 6Y/6Y and 6F/6F mice. Data are from 10 gender-matched 8-week-old mice of each genotype. For b–e, data were analysed by unpaired t-test (two tailed) and are represented as mean±s.d. *P<0.05; **P<0.01. (f) CDR3 lengths (per cent of total in-frame reads) of TCR-Vβ loci from naïve CD4-SP T-cells from 6Y/6Y or 6F/6F mice.
