Figure 4
High motility of naïve CD4+ T cells in healthy lymphoid tissue. MACS® sorted OT2 tdRFP expressing CD4+ naïve T cells were intravenously injected into healthy C57BL/6 RAG 1 -/- mice in order to perform time lapse TPLSM on popliteal lymph nodes at 8 - 96 hours after transfer. (A) Injected OT2 tdRFP cells were isolated from lymph nodes of C57BL/6 OT2 tdRFP mice and subjected to FACS analysis to measure surface expression of CD62L, CD25, and CD44 at 96 hours after transfer. Dot Plots reveal analysis on CD4+ tdRFP positive lymphocytes. (B) High motility of naïve T lymphocytes in lymph nodes is revealed by trajectory vector blots derived from cell tracking analysis of time lapse TPLSM at 24 hours after transfer (left). Each vector represents displacement of individual cells for an imaging period of 30 min (one image every minute) relative to their starting position. A corresponding time lapse series of naïve cell migration is shown on the right. The dashed arrow represents migration of one single cell exemplarily. (C) Quantification of naïve CD4+ T cell movement in isolated lymph nodes. The mean track velocity is 0.16 ± 0.06 μm/sec (± SD, N = 73).