CCl_4慢性肝损致无白蛋白受体鼠对移植骨髓细胞肝细胞增殖的影响

Effect of analbuminemic recipient rats resulted from chronic hepatic damage caused by CCl_4 on the proliferation of hepatocyte derived from bone marrow cells transplanted into the analbuminemic rats

目的观察和研究F344来源的骨髓细胞(bone marrow cells,BMCs)能否驻存于γ-全身照射的先天性无白蛋白大鼠的骨髓,进而转化为产白蛋白肝细胞,移植后给予四氯化碳(carbon tetracholoride,CCl4)后对这些细胞增殖的影响。方法雄性F344大鼠为供体,而雄性F344alb(先天性无白蛋白大鼠)为受体,分为4组:组Ⅰ(n=10)为正常对照组,不接受肝损处理,无全身射线照射和阴茎静脉骨髓细胞移植;组Ⅱ(n=10)为肝损无移植组,只接受肝损处理,无全身射线照射和阴茎静脉骨髓细胞移植;组Ⅲ(n=10)为正常移植组,全身射线照射后阴茎静脉移植骨髓细胞1×107;组Ⅳ(n=10)为肝损移植组,接受CCl4注射肝损,全身射线照射后阴茎静脉骨髓细胞移植1×107BMCs,其中,γ-照射剂量为7.5Gy,F344大鼠的BMCs经受体的阴茎静脉注入。移植后四周,CCl4腹腔内注射铸成大鼠慢性肝损模型,细胞移植12周后,处死大鼠。肝脏切片用抗白蛋白抗体行白蛋白免疫染色,检测从受体骨髓细胞和肝脏切片中呈多于6个白蛋白阳性簇状分布的肝细胞群中提取的DNA和血清中白蛋白的水平。结果①尽管组Ⅰ肝脏切片可发现少量散在的1个或2个白蛋白阳性肝细胞,但是白蛋白阳性肝细胞呈多于6个的簇状分布仅发现于γ射线全身照射后接受BMCs移植的肝切片中(组Ⅲ和组Ⅳ),而且组Ⅳ中呈多于6个的簇状分布的肝细胞数明显多于组Ⅲ,有统计学意义。②从F344alb受体(组Ⅲ和组Ⅳ)骨髓细胞及肝脏切片中微切的呈多于6个白蛋白阳性簇状分布的肝细胞群中提取的DNA中可检测到正常的白蛋白基因序列。③组Ⅳ较组Ⅲ血清中白蛋白水平显著升高。结论①F344来源的骨髓细胞移植入全身射线照射的F344alb受体,可驻存于F344alb受体的骨髓内,进而转化为产白蛋白的肝细胞。②F344来源的骨髓细胞移植入全身射线照射的F344alb受体,4周后CCl4腹腔内注射铸成大鼠慢性肝损模型可明显增加骨髓细胞的增殖。③全身射线照射后移植F344供体骨髓细胞,之后CCl4腹腔内注射铸成大鼠慢性肝损模型的F344alb受体的外周血中白蛋白水平可明显提高。

Objective To observe and investigate whether BMCs derived from F344 can harbor in the bone marrow cells （BMCs） congenic Nagase’s analbuminemic rats （F344alb） recipients who had undergone γ-irradiation and can further raise albumin-producing hepatocytes in the liver. Methods Six weeks old male Fischer 344 rats （F344） were used as donors, and six weeks old male F344alb as recipients. All F344alb were divided into 4 groups： group Ⅰ （n=10） was untreated; group Ⅱ （n=10） was treated with CCl4 but no γ-irradiation and transplantation; group Ⅲ （n=10） was transplanted with 1×107 BMCs after γ-irradiation, but without CCl4 treatment; group Ⅳ （n=10） was transplanted with 1×107 BMCs after γ-irradiation, with CCl4 treatment. The BMCs prepared from the donors were infused via the penial veins of recipients immediately after whole body γ-irradiation （7.5 Gy） and CCl4 treatment： 4 weeks after BMCs transplantation, CCl4 were injected into peritoneal cavity twice a week for 4 weeks. Animals were sacrificed in the 12th weeks after transplantation. Slices of the liver were stained by albumin immunostaining with anti-rat albumin antibody. DNA extracted from BMCs and dissected alb＋ clusters consisting of more than 6 alb＋ hepatocytes as well as serum albumin levels of recipients were examined. Results ①Although single or double cells of albumin positive （alb＋） hepatocytes were seen in the livers of untreated F344alb （group Ⅰ）, clusters consisting of more than 6 alb＋ hepatocytes were only detected in the livers of recipients that received transplantation of BMCs after γ-irradiation with or without CCl4 liver damage （group Ⅲ and Ⅳ）. ②The normal gene sequence of albumin was detected in BMCs of F344alb recipients and dissected alb＋ clusters consisting of more than 6 alb＋ hepatocytes in F344alb transplanted with BMCs after γ-irradiation （group Ⅲ and Ⅳ）. ③Serum albumin levels of F344alb recipients in group Ⅲ and Ⅳ were significantly increased. Conclusion ①These findings indicate that BMCs can harbor in BMCs of the F344alb recipients γ-irradiated and further more can raise albuminproducing hepatocytes in the liver. ②After BMCs transplantation, liver damage by CCl4 can indeed promote the proliferation of the BMCs in liver.