Loss of ST3Gal-IV leads to impaired T-cell development in MBMC mice. Flow cytometric analysis of thymocytes of MBMC mice generated as described in Figure 1. Dot plots show the frequency of CD4 single-positive, CD8 SP, DN, and double-positive (DP) thymocytes (A) or the frequency of DN1 to DN4 populations among total DN cells (B) of 1 representative mouse. Histograms indicate the frequency of WT (CD45.1⁺) and ST3Gal-IV–deficient (KO) (CD45.1⁻) cells among total CD45.2⁺ gated donor cells. Bars show the mean ± SEM frequency of WT (blue) and ST3Gal-IV–deficient (red) cells among all donor cells in indicated gates of 2 independent experiments with 14 mice total per group. *P < .05 by 2-tailed Student t test.