Impaired immune responses toward alloantigens and tumor cells but normal thymic selection in mice deficient in the beta2 integrin leukocyte function-associated antigen-1.

Abstract We have generated mice deficient in the beta2 integrin LFA-1 by targeted disruption of the CD11a gene in embryonic stem cells. In vitro LFA-1 -/- cells exhibit a delayed proliferative response toward alloantigens in the MLR. In vivo the host-vs-graft reaction toward injected allogeneic cells is also reduced. Alloantigen-specific CTLs generated from LFA-1 -/- mice are impaired in their cytotoxic activity toward allogeneic spleen cells as well as cell line targets. The proliferative response of LFA-1 -/- splenocytes following stimulation by LPS, PMA plus ionomycin, or immobilized anti-CD3epsilon mAb is normal, but Con A-stimulated proliferation is greatly diminished. We observe typical edema formation in a delayed type hypersensitivity reaction to SRBC with normal extravasation of leukocytes and demonstrate recruitment of neutrophils to an LPS-induced inflammatory site in these mice, suggesting that LFA-1 does not play an essential role in lymphocyte homing and leukocyte extravasation. We further show that LFA-1 -/- mice are susceptible to metastasis of B16 melanoma tumors, although their in vitro NK cell activity appears normal. A study of LFA-1 -/- mice expressing transgenic TCRs indicates that thymic maturation and selection of T cells are unaffected by the loss of LFA-1. Our results indicate that LFA-1 is important for alloantigen-triggered T cell proliferation and cytotoxicity, for Con A stimulation of T cells, and in tumor rejection. It does not appear to play an essential role in lymphocyte homing and leukocyte extravasation or in T cell maturation and selection in the thymus.</jats:p

Glucagon-Like Peptide-2 Analogue ZP1849 Augments Colonic Anastomotic Wound Healing

Background. The enteroendocrine hormone glucagon-like peptide- (GLP-) 2 is a potent trophic factor in the gastrointestinal tract. The GLP-2 receptor (GLP-2R) is expressed in the stroma of the large bowel wall, which is the major therapeutic target area to prevent anastomotic leakage. We investigated the efficacy of the long-acting GLP-2 analogue ZP1849 on colonic anastomotic wound healing. Methods. Eighty-seven male Wistar rats were stratified into four groups and received daily treatment with vehicle or ZP1849 starting one day before (day -1) end-to-end anastomosis was constructed in the left colon on day 0, and on days 0 (resected colon segment), 3, and 5, gene expressions of GLP-2R, Ki67, insulin-like growth factor- (IGF-) 1, type I (COL1A1) and type III (COL3A1) procollagens, cyclooxygenase- (COX-) 1, COX-2, and matrix metalloproteinase- (MMP-) 7 were quantified by RT-qPCR. Breaking strength, myeloperoxidase (MPO), transforming growth factor- (TGF-) β1, and soluble collagen proteins were measured on days 3 and 5. Results. ZP1849 treatment increased Ki67 (P<0.0001) and IGF-1 (P<0.05) mRNA levels in noninjured colon day 0, and postoperatively in the anastomotic wounds compared to vehicle-treated rats. ZP1849-treated rats had increased (P=0.042) anastomotic breaking strength at day 5 compared with vehicle. COL1A1 and COL3A1 mRNA levels (P<0.0001) and soluble collagen proteins (P<0.05) increased from day 3 to day 5 in ZP1849-treated rats, but not in vehicle-treated rats. COX-2 mRNA and MPO protein levels decreased from day 3 to day 5 (P<0.001) in both groups. ZP1849 treatment reduced TGF-β1 protein levels on day 5 (P<0.001) but did not impact MMP-7 transcription. Conclusions. The GLP-2 analogue ZP1849 increased breaking strength, IGF-1 expression, and cell proliferation, which may be beneficial for colonic anastomotic wound healing

Glucagon-Like Peptide-2 Analogue ZP1849 Augments Colonic Anastomotic Wound Healing

Background. The enteroendocrine hormone glucagon-like peptide- (GLP-) 2 is a potent trophic factor in the gastrointestinal tract. The GLP-2 receptor (GLP-2R) is expressed in the stroma of the large bowel wall, which is the major therapeutic target area to prevent anastomotic leakage. We investigated the efficacy of the long-acting GLP-2 analogue ZP1849 on colonic anastomotic wound healing. Methods. Eighty-seven male Wistar rats were stratified into four groups and received daily treatment with vehicle or ZP1849 starting one day before (day -1) end-to-end anastomosis was constructed in the left colon on day 0, and on days 0 (resected colon segment), 3, and 5, gene expressions of GLP-2R, Ki67, insulin-like growth factor- (IGF-) 1, type I (COL1A1) and type III (COL3A1) procollagens, cyclooxygenase- (COX-) 1, COX-2, and matrix metalloproteinase- (MMP-) 7 were quantified by RT-qPCR. Breaking strength, myeloperoxidase (MPO), transforming growth factor- (TGF-) β1, and soluble collagen proteins were measured on days 3 and 5. Results. ZP1849 treatment increased Ki67 (P&lt;0.0001) and IGF-1 (P&lt;0.05) mRNA levels in noninjured colon day 0, and postoperatively in the anastomotic wounds compared to vehicle-treated rats. ZP1849-treated rats had increased (P=0.042) anastomotic breaking strength at day 5 compared with vehicle. COL1A1 and COL3A1 mRNA levels (P&lt;0.0001) and soluble collagen proteins (P&lt;0.05) increased from day 3 to day 5 in ZP1849-treated rats, but not in vehicle-treated rats. COX-2 mRNA and MPO protein levels decreased from day 3 to day 5 (P&lt;0.001) in both groups. ZP1849 treatment reduced TGF-β1 protein levels on day 5 (P&lt;0.001) but did not impact MMP-7 transcription. Conclusions. The GLP-2 analogue ZP1849 increased breaking strength, IGF-1 expression, and cell proliferation, which may be beneficial for colonic anastomotic wound healing.</jats:p