Background: L-selectin (CD62L) is a cell surface adhesion molecule recently shown to play a critical role in determining endometrial receptivity and implantation in humans. By contrast, the L-selectin ligand is missin...Background: L-selectin (CD62L) is a cell surface adhesion molecule recently shown to play a critical role in determining endometrial receptivity and implantation in humans. By contrast, the L-selectin ligand is missing from the rodent endometrium. Interestingly, CD62L (L-selectin)-deficient BALB/c mice delivered significantly higher numbers of viable offspring than wild type controls via mechanisms yet to be defined. Methods: Nulliparous CD62L-deficient (8-10-week-old, n = 25) or wild type (n = 18) females were mated with 43 age-matched males. Animals were sacrificed at gestational day (GD) 9.5. Tissue samples were analyzed by immunostaining and flow cytometry. Results: Mating wild type and CD62L-deficient BALB/c mice revealed that the increased birth rate was due to the CD62L deficiency in females. Flow cytometric analysis demonstrated significant differences in the number of natural killer (NK) cells present in the uterus of pregnant CD62L- deficient mice compared to controls. Immunohistochemistry confirmed NK cell accumulation at the fetal-maternal interface. Discussion: Uterine NK cells have been shown to peak at GD 8-10 at the fetal-maternal interface. NK cells might regulate mouse fertility rates by facilitating development of the maternal spiral arteries, thereby stimulating the formation of larger vessels that facilitate intrauterine survival, however, their role is not obligate to spiral artery development. Conclusions: Diminished CD62L expression modified immune cell trafficking into the uterus of pregnant mice generating a microenvironment primarily dominated by NK cells resulting in improved embryonic survival rates.展开更多
AIM: To determine the DNA binding activity and protein levels of the Ku70/80 heterodimer, the functional mediator of the NHEJ activity, in human colorectal carcinogenesis.METHODS: The Ku70/80 DNA-binding activity was ...AIM: To determine the DNA binding activity and protein levels of the Ku70/80 heterodimer, the functional mediator of the NHEJ activity, in human colorectal carcinogenesis.METHODS: The Ku70/80 DNA-binding activity was determined by electrophoretic mobility shift assays in 20 colon adenoma and 15 colorectal cancer samples as well as matched normal colonic tissues. Nuclear and cytoplasmic protein expression was determined by immunohistochemistry and Western blot analysis.RESULTS: A statistically significant difference was found in both adenomas and carcinomas as compared to matched normal colonic mucosa (P＜0.00). However,changes in binding activity were not homogenous with approximately 50% of the tumors showing a clear increase in the binding activity, 30% displaying a modest increase and 15% showing a decrease of the activity.Tumors, with increased DNA-binding activity, also showed a statistically significant increase in Ku70 and Ku86nuclear expression, as determined by Western blot and immunohistochemical analyses (P＜0.001). Cytoplasmic protein expression was found in pathological samples,but not in normal tissues either from tumor patients or from healthy subjects.CONCLUSION: Overall, our DNA-binding activity and protein level are consistent with a substantial activation of the NHEJ pathway in colorectal tumors. Since the NHEJ is an error prone mechanism, its abnormal activation can result in chromosomal instability and ultimately lead to tumorigenesis.展开更多
文摘Background: L-selectin (CD62L) is a cell surface adhesion molecule recently shown to play a critical role in determining endometrial receptivity and implantation in humans. By contrast, the L-selectin ligand is missing from the rodent endometrium. Interestingly, CD62L (L-selectin)-deficient BALB/c mice delivered significantly higher numbers of viable offspring than wild type controls via mechanisms yet to be defined. Methods: Nulliparous CD62L-deficient (8-10-week-old, n = 25) or wild type (n = 18) females were mated with 43 age-matched males. Animals were sacrificed at gestational day (GD) 9.5. Tissue samples were analyzed by immunostaining and flow cytometry. Results: Mating wild type and CD62L-deficient BALB/c mice revealed that the increased birth rate was due to the CD62L deficiency in females. Flow cytometric analysis demonstrated significant differences in the number of natural killer (NK) cells present in the uterus of pregnant CD62L- deficient mice compared to controls. Immunohistochemistry confirmed NK cell accumulation at the fetal-maternal interface. Discussion: Uterine NK cells have been shown to peak at GD 8-10 at the fetal-maternal interface. NK cells might regulate mouse fertility rates by facilitating development of the maternal spiral arteries, thereby stimulating the formation of larger vessels that facilitate intrauterine survival, however, their role is not obligate to spiral artery development. Conclusions: Diminished CD62L expression modified immune cell trafficking into the uterus of pregnant mice generating a microenvironment primarily dominated by NK cells resulting in improved embryonic survival rates.
基金Supported by Italian Ministero della Salute, IRCCS, RC0302TG13 by Ministero dell'Istruzíone, Università e Ricerca scientifica e tecnologica (MIUR), COFIN2002, to the Universita Campus Bio-Medico
文摘AIM: To determine the DNA binding activity and protein levels of the Ku70/80 heterodimer, the functional mediator of the NHEJ activity, in human colorectal carcinogenesis.METHODS: The Ku70/80 DNA-binding activity was determined by electrophoretic mobility shift assays in 20 colon adenoma and 15 colorectal cancer samples as well as matched normal colonic tissues. Nuclear and cytoplasmic protein expression was determined by immunohistochemistry and Western blot analysis.RESULTS: A statistically significant difference was found in both adenomas and carcinomas as compared to matched normal colonic mucosa (P＜0.00). However,changes in binding activity were not homogenous with approximately 50% of the tumors showing a clear increase in the binding activity, 30% displaying a modest increase and 15% showing a decrease of the activity.Tumors, with increased DNA-binding activity, also showed a statistically significant increase in Ku70 and Ku86nuclear expression, as determined by Western blot and immunohistochemical analyses (P＜0.001). Cytoplasmic protein expression was found in pathological samples,but not in normal tissues either from tumor patients or from healthy subjects.CONCLUSION: Overall, our DNA-binding activity and protein level are consistent with a substantial activation of the NHEJ pathway in colorectal tumors. Since the NHEJ is an error prone mechanism, its abnormal activation can result in chromosomal instability and ultimately lead to tumorigenesis.
