Expansion and Activation Kinetics of Immune Cells during Early Phase of GVHD in Mouse Model Based on Chemotherapy Conditioning

Figure 4

Chimerism and activation pattern of donor cytotoxic T cells in the spleen of GVHD mice. BALB/c mice were transplanted with 20×10⁶ and 30×10⁶ BM and SP cells from either allogeneic (C57BL/6) or syngeneic (BALB/c) donors. Spleens of transplanted recipients were evaluated using flowcytometry and histopathology methods. (a) Frequency of donor versus recipient T cells at different time points in the spleen of GVHD mice. (◆): donor (H-2Kb), (◊): host (H-2Kd) cells. (b) Large granular lymphocytes appeared 5 days after BMT in the spleen of GVHD mice however these cells decreased dramatically at day 7 after BMT. (c) Most of the granular large T cells (upper gate) at day +5 originated from donor. (d, e) Expansion pattern of naïve (CD44^lowCD62^high) and effector memory (CD44^highCD62^low) T cells in the spleen of (d) allogeneic and (e) syngeneic transplanted mice. (f) Immunohistostaining of spleen in allogeneic (upper row) and syngeneic (lower row) setting indicate extensive spreading of CD8+ T cells (brown spots) in the spleen of allogeneic transplanted mice 5 days after BMT. (◆): naïve (CD44^lowCD62^high), (◊): effector memory (CD44^highCD62^low) in allogeneic and syngeneic setting, (⬤): naïve (CD44^lowCD62^high), (▲): effector memory (CD44^highCD62^low) in normal BALB/c mice. Differences were analyzed statistically employing U-test, compared between groups (^∗𝑃<.05).

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