PMC

Anti–DNAM-1 mAb suppressed the development of acute GVHD. (A) After sublethal irradiation, B6C3F1 mice received splenocytes from WT B6 mice. The recipient mice were i.p. injected with anti–DNAM-1 (TX42) (n = 14) or control antibodies (n = 16) every other day from day −1 until day 17 after transplantation. B6C3F1 mice that received irradiation only are also shown (n = 10). Data were pooled from three independent experiments. (B) The liver and small intestine of mice on day 25 after transplantation were stained with H&E and histologically analyzed. The organs of three mice in each group were analyzed and representative data of a mouse in each is shown. (Scale bars, 100 μm.)

DNAM-1 expression on donor CD8⁺ T cells is involved in exacerbation of acute GVHD. (A) After sublethal irradiation, B6C3F1 mice received splenocytes from DNAM-1 WT (n = 14) or KO B6 (n = 16) mice. B6C3F1 mice that received irradiation only are also shown (n = 5). Data are representative of two independent experiments. (B) After sublethal irradiation, B6C3F1 recipient mice received TCD-SP plus CD8⁺ T cells from DNAM-1 WT or KO B6 mice and CD4⁺ T cells from DNAM-1 WT or KO B6 mice (n = 10 in each group). Data are pooled from two independent experiments. (C) After sublethal irradiation, DNAM-1 WT (n = 9) or KO (n = 18) CBF1 mice received splenocytes from DNAM-1 WT B6 mice. DNAM-1 WT and KO CBF1 mice that received irradiation alone are also shown (n = 5 and 7, respectively). The experiments were independently performed four times and pooled data from all of the experiments are shown.

DNAM-1 is involved in donor CD8⁺ T-cell proliferation in recipient mice after transplantation. (A) After sublethal irradiation, B6C3F1 mice received splenocytes from DNAM-1 WT or KO B6 mice. The infiltrating cells in the liver and small intestine in recipient mice (n = 3) on day 14 after transplantation were separated, and each donor-derived (H-2K^k−) lymphocyte subset was determined by flow cytometry. Data are representative of two independent experiments. (B) Resting CD8⁺ T cells purified from naive DNAM-1 WT or KO B6 mice (Left) and donor effector CD8⁺ T cells purified from B6C3F1 mice that received WT or KO B6 splenocytes (Right) were labeled with CFSE, cocultured with mitomycin C-treated syngeneic (B6) or allogeneic (B6C3F1) splenocytes for 3 d, and analyzed by flow cytometry. Data are representative from three independent experiments with similar results. *P < 0.05. Error bars show SD.

Anti–DNAM-1 mAb ameliorated overt acute GVHD. (A and B) B6C3F1 mice received splenocytes from WT B6 mice after sublethal irradiation. The recipient mice were injected i.p. with 300 μg anti–DNAM-1 (TX42) (n = 11) or control antibodies (n = 11) every week from day 14 until day 77 after transplantation (A), or 1.0 mg TX42 (n = 19) or control antibodies (n = 19) once on day 14 (B). B6C3F1 mice that received irradiation only are also shown (n = 8 or 9). (C) C3 mice were transplanted with bone marrow cells and spleen T cells from B6 mice after lethal irradiation. The recipient C3 mice were injected i.p. with 1.0 mg TX42 (n = 8) or control antibodies (n = 8) once on day 14. Recipient B6 mice that received transplantation with bone marrow cells and T cells after lethal irradiation (Syngeneic BMT) are also shown (n = 6). Data are representative of two independent experiments with similar results in A. Data are pooled from two independent experiments in B and C.

DNAM-1 expression on donor T cells was up-regulated in recipient mice. (A and B) After sublethal irradiation, B6C3F1 (allogeneic) or B6 (syngeneic) recipient mice received CFSE-labeled splenocytes from WT B6 mice, and CFSE⁺ donor CD8⁺ T cells in the spleen were analyzed by flow cytometry for the expression and mean fluorescence intensity (MFI) of DNAM-1 on day 3 after transplantation. (C) CD8⁺ T cells from B6 mice were stimulated with plate-coated anti-CD3 and analyzed for the expression of DNAM-1 on CD8⁺ T cells by flow cytometry. (D) The correlation between DNAM-1 expression on donor CD8⁺ T cells on day 21 and ALT values on day 28 in recipients injected with control Ig or TX42 was statistically evaluated. Data are representative of three independent experiments with similar results, respectively. ***P < 0.005; *P < 0.05. Error bars show SD.