骨髓移植治疗乙肝

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过激免疫在治疗慢性乙肝中的应用
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第一军医大学南方医院感染内科（510515）　
邢同京（综述）　章　廉（审校）
    摘 要　

    既往临床观察表明，一些合并乙型肝炎病毒（HBV）感染的血液病患者接受乙型肝炎表面抗体（抗-HBs）阳性供者髓髓后，在造血和免疫功能重建的同时，其体内的HBV也被清除。近年来，对这一现象的认识逐渐深入，有关研究报道不断增多，本文就此方面的研究进展予以综述。

    特异性细胞过继免疫是指特异性抗原刺激的自体或异体的免疫细胞输入患者体内，诱导机体产生特异性的免疫应答。近年来的基础和临床研究表明，慢性HBV感染者大多存在免疫耐受，通过特异性的细胞过继免疫，能够打破其免疫耐受，激发充分的免疫应答，从而清除HBV。本文就此方面的研究进展综述如下。

1.动物实验

    动物实验研究表明，细胞过继免疫是可行的。Shouval等[1]研究发现：用重组的乙型肝炎表面抗原（HBsAg）免疫供者小鼠，然后将其骨髓移植给免疫抑制的受者小鼠，受者体内可检测到抗-HBs，提示供者对乙型肝炎的免疫功能已转移到受者体内。Ilan等[2]在对无胸腺小鼠的研究中发现：给事先注射Hep3B系人肝癌细胞的小鼠移植用重组HBsAg免疫小鼠的骨髓，9周后与对照组比较，肿瘤的体积和血清中甲胎球蛋白的水平明显减少和下降，去除T细胞的抗-HBs阳性骨髓也能减小肿瘤的体积，说明对HBV的过继免疫能抑制肝癌细胞的生长。

2.临床研究

2.1 骨髓移植

    骨髓移植是目前治疗白血病等许多疾病的有效方法，它的主要机制是基于其造血和免疫功能重建。由于HBV感染的高发生率，在骨髓移植（BMT）中，合并HBV感染者接受BMT是不可避免的。免疫功能的重建对于HBV感染者既有有利的一面，也有不利的一面。早期的临床观察发现：一些合并HBV感染的白血病患者接受了抗-HBs阳性的供者骨髓后，在造血和免疫功能重建的同时，其体内的HBV也得到清除。Ilan等[3]报道了12例患者接受抗-HBs/抗-HBc阳性的供者骨髓后，30～120天其血清中的抗-HBs检测为阳性，而8例接受单纯抗-HBs阳性骨髓的患者，在9～42天其血清抗-HBs中即为阳性，提示供者对HBV的免疫功能通过骨髓转移给受者的效果。Lau等[4]报道21例合并HBV感染的患者，其中5例接受抗-HBs/抗-HBc阳性的骨髓移植（2例产生持续的HBsAg阴转和抗-HBs阳转，这2例患者移植前HBeAg和HBV DNA均为阴性，且均为成年人；1例发生一过性阴转；而2例未发生阴转者均为儿童，且病毒为高复制，其中1例患者与供者HLA抗原有2个位点不一致，另1例接受经疫苗免疫产生抗-HBs的供者骨髓）。另16例接受抗-HBs阴性供者骨髓的患者，无一例发生阴转，说明过继免疫在HBV的清除中起重要作用，但也可能存在其他因素的影响，如病毒复制的水平，获得免疫的方式等。随后Lau等[5]又观察了13例接受抗-HBs阳性供者的骨髓，其中抗-HBs/抗-HBc阳性6例，抗-HBc阳性7例，4例HBsAg阴转，抗-HBs转阳，且全部都是接受抗-HBs/抗-HBs阳性骨髓的患者；而7例接受仅抗-HBs阳性的患者无一例阴转，作者认为疫苗免疫对于HBV的清除是不足的，而且发生清除的时间一般在BMT后3～6个月。Brugger等[6，7]分别报道一例接受乙型肝炎疫苗免疫的供者骨髓21天，另一例接受经自然感染的骨髓后28天，其血清中的HBsAg阴转，HBV DNA消失。分析原因可能是对于免疫耐受的患者，接受在BMT前经疫苗免疫的健康供者的骨髓，产生特异的CTL反应较快，而接受在BMT前经自然感染免疫患者的骨髓，产生特异的CTL反应需要较长的时间。

    对于合并HBV感染的需移植者，接受BMT后，常需要大剂量的免疫抑制剂治疗，这很可能诱发肝炎的活动，甚至发生重型肝炎。Caselitz等[8]研究认为在合并HBV感染的移植患者中，由于肝衰竭引起死亡的可能性至少部分与HBV的再活动有关。Chen等[9]报告了43例接受BMT的HBV感染者，其中32例接受异基因BMT，11例接受自体BMT。随访1～11年，接受异基因BMT的患者有26（81.3%）例发生肝功能损害，5例发展为暴发型肝炎；在接受自体BMT的患者有4（36.4%）例发生肝功能损害，无一例发生暴发型肝炎，提示自身移植的安全性较高。Lau等[5]报道4例接受抗-HBs阳性供者的骨髓发生HBV清除的患者中，均出现不同程度的肝损害，但没有出现暴发型肝炎，原因可能与CTL的非细胞毒性作用机制有关。

    如何防止和减少HBV感染者接受BMT后发生肝脏损害，Dhin等[10]观察33例抗HBs/抗-HBc阳性的患者按受BMT后，随访20个月，结果显示33例患者的标志物无变化。在停止使用免疫抑制剂后，有4例患者的抗-HBs和抗-HBc消失，HBsAg、HBeAg和HBV DNA转阳，且发生急性肝炎。而在接受抗-HBs阳性供者的骨髓后，则没有活化。作者认为，尽管只有4例发生血清学逆转换，但肝炎再活动的危险性是比较大的（20.5%），建议供者可预防性地应用乙型肝炎疫苗或者高效价的乙型肝炎免疫球蛋白（HBIG）。Daily等[11]报道，应用丙种球蛋白肌注也能起到预防作用。最近，Lau等[5]报道应用泛昔洛韦降低合并乙型肝炎的血液病患者的病毒水平，可减少肝脏损害的发生率。

2.2 外周血淋巴细胞（PBL）输注

    由于BMT的高死亡率的高费用，其应用受到限制，因此需要加以改进。Ilan等[12]研究发现：不仅供者骨髓可产生过继免疫，而且输注PBL也能达到此效果，这为过继免疫的应用提供了极大的方便。

2.3 造血干细胞移植

    由于HBV不仅能感染患者的骨髓基质细胞，而且还感染患者的外周血淋巴细胞，并在其中发生转录，因此对于应用自身的BMT和PBLs可能受限。Ust[13]观察了12例接受HBsAg阳性供者的造血干细胞移植的患者，其中HBsAg阳性8例，阴性4例。随访13.2个月（中位数），8例HBsAg阳性患者中有1例死于肝衰竭，1例ALT升高；4例阴性患者无一例发生HBV感染。作者认为，造血干细胞移植可能会减少HBV感染，且HBsAg阳性并不是造血干细胞移植的反指证，除非HBV感染处于高复制水平。

3. 过继免疫的作用机制

    关于过继免疫的作用机制，目前尚不十分清楚。有作者认为，CD8+T细胞的作用要大于CD4+T细胞，Ilan等[3]的研究发现，去除了T细胞的骨髓也能产生过继免疫，但抗体的滴度较低。

4. 展望

    从以上可以看出，接受BMT后的HBsAg阴转率明显高于自发的转换率和干扰素治疗后的阴转率，在目前尚缺乏有效清除HBV的情况下，过继免疫给我们提供一种治疗慢性乙型肝炎的有效方法，由于BMT的高死亡率和高费用，限制了其临床应用。因此，深入探讨过继免疫的作用机制，不断加以改进，有可能使这一方法应用到慢性乙型肝炎的治疗中。

参考文献

1 Shouval D et al.Hepatology,1993;17:955～959

2 Ilan Y et al.J Hepatol,1997;27:170～175

3 Ilan Y et al Hepatology,1993;18:246～252

4 Lau GKK et al.Hepatology,1997;25:1497～1501

5 Lau GKK et al.J Infect Dis,1998;178:1585～1591

6 Brugger SA et al.Lancet ,1997;349:996～997

7 Ilan Y et al.Gastroenterology,1993;104:1818～1821

8 Caselitz M et al.J Hepatol,1997;27:572～577

9 Chen PM et al.Transplantation,1999;67:11,1425～1433

10 Dhin N et al.Transplantation,66(5):616～619

11 Daily J et al.Bone Marrow Transplant,1998;21:739～742

12 Ilan Y et al.Clin Exp Immunol,1994;97:229～302

13 Ust C et al.J Hepatol.1999;31(2):202～209

                      国外医学流行病学传染病学分册 (.00026000W03.)

[此贴子已经被作者于2004-7-20 18:54:57编辑过]

天狼星

骨髓移植或治疗性复合疫苗或能根治乙肝？

  

　

战胜乙肝网 http://vyigan.myrice.com/



2002-4-15 摘自上海肝病在线 金医生




天然HBV免疫的供体的异体骨髓移植即骨髓干细胞移植是效果最佳而又最为昂贵又极不切实际的HBV根治方法

----谈治疗性复合HBV系列疫苗的疫苗组方设计

HBV感染者因没有正常的抗HBV免疫功能，故不宜作BMT的供体，否则可致受体HBV感染（参考文献1-3）。但又有不少报导（参考文献3-14），HBV感染者受体如采用天然HBV免疫的供体的骨髓血/干细胞进行骨髓移植（ bone marrow transplant，BMT）则因过继了供体的免疫功能如APC/DC和CD4+/TH功能，则HBV可被清除而抗HBS抗体转阳。研究深入后发现其过继免疫除与天然HBV免疫的供体的HBVC区抗原特异性CD4+过继到受者体内有关外，还与骨髓其他细胞（APC/DC）有关（参考文献5~6，15）。

虽然天然HBV免疫的供体的异体骨髓移植即骨髓干细胞移植治疗HBV感染疗效显著，但不可否认，广泛开展/进行天然HBV免疫的供体的异体骨髓移植即骨髓干细胞移植是极其困难的，首先费用大（20-30万最少），其次MHC/HLA配对合适者难找，而又同时满足天然HBV免疫和MHC/HLA配对合适二个条件的则更难找。因此天然HBV免疫的供体的异体骨髓移植即骨髓干细胞移植是效果最佳而又最为昂贵又极不切实际的HBV根治方法。

采用药物激活HBV感染者的HBV特异性的免疫感应与效应功能的治疗性复合HBV系列疫苗，为替代天然HBV免疫的供体的异体骨髓移植而达到清除HBV的目的，为此治疗性复合HBV系列疫苗应考虑激活HBV特异性的免疫感应与效应功能的诸多药物与HBV疫苗抗原相结合，如激活免疫感应APC/DC功能的有GM-CSF等，而激活TH和CTL及B细胞以及NK、NK-T等免疫效应细胞功能的有牛磺酸等，而HBV疫苗抗原应包括HBS区、前S1区、前S2区及HBV C区。


1）Ireland J, Hino K, Lau GK, Cheng CC, Carman WF. Failed adoptive immunity transfer: reactivation or reinfection? J Viral Hepat 1999 Jan;6(1):73-8

A 26-year-old female bone marrow transplant (BMT) recipient was hepatitis B surface antigen (HBsAg) and hepatitis B e antibody (HBeAb) positive. The donor, her human leucocyte antigen (HLA)-compatible sister, was HBsAg negative but hepatitis B surface antibody (HBsAb) and hepatitis B core antibody (HBcAb) positive. Twelve weeks post-BMT the patient became HBsAg negative, as determined using a monoclonal antibody-based assay. At 16 weeks post-BMT, HBsAg became undetectable by monoclonal and polyclonal immunoassay with seroconversion to HBsAb; however, at 24 weeks post-BMT the patient again became HBsAg positive. Both the recipient and the donor were retrospectively tested by hepatitis B virus (HBV) polymerase chain reaction (PCR) and found to be positive. The recipient displayed variants at amino acids 4 and 47 of the surface (S) gene prior to BMT. These mutations were not detected 32 weeks post-BMT when the S gene sequence was identical to that of an adr prototype. The donor was found to have four unique amino acid substitutions at positions 30, 98, 101 and 210 of the S gene. However, in vitro-expressed HBsAg from the donor was detected by commercial kits and an immunofluorescence assay, indicating that antigenic alteration did not explain HBsAg negativity. This donor highlights the value of PCR as the gold standard test for current HBV infection. It also demonstrates that discordance between two commercial HBsAg assays may not always be caused by antigenic variants. The second episode of hepatitis may theoretically have been caused by reactivation, selection of an escape mutant by HBsAb, reinfection or recombination. We suggest it was reactivation because none of the donor variants was seen in the recipient post-BMT.

因供体是一HBVS区变异株，该HBV感染者的受体（病人）BMT后，故HBV感染者的受体出现一过性HBS阶段AG消失后，因其过继其供体（HLA/MHC相容性妹妹）的异常免疫（免疫压力偏倚而致HBV S区变异而HBVDNA仍阳性）功能，仍不能最后清除HBV而复HBS AG阳性。但受体没有过继其供体的HBV变异株。-----说明HBV感染者因没有正常的抗HBV免疫功能，故不宜作BMT的供体。

2） Locasciulli A, Alberti A, Bandini G, Polchi P, Arcese W, Alessandrino P, Bosi A, Testa M, Bacigalupo A. Allogeneic bone marrow transplantation from HBsAg+ donors: a multicenter study from the Gruppo Italiano Trapianto di Midollo Osseo (GITMO).Blood 1995 Oct 15;86(8):3236-40

Hepatitis B virus (HBV)-infected individuals are occasionally used as donors for bone marrow transplantation (BMT). We studied the rate of HBV infection and the clinical expression of the associated liver disease in patients receiving marrow from HBsAg+ donors. We performed a retrospective survey in 14 BMT units in Italy in which all BMTs performed between 1984 and 1994 were reviewed and those involving HBsAg+ donors were identified. Donors and recipients were analyzed for HBV markers and liver disease. A total of 24 of 2,586 patients (0.9%) had received an HBsAg+ marrow. HBsAg became detectable in 22% of pre-BMT HBsAg- patients, but only 5.5% became chronic HBsAg carriers. Antigenemia developed more frequently in anti-HBs- compared with anti-HBs+ patients independently of passive prophylaxis with hyperimmune anti-HBs Ig, although the difference was not significant. Severe liver failure with death occurred in 21% of patients, which was a value greater than that generally observed after BMT in our units (3.7%). Patients with an anti-HBe+ donor had higher frequency of liver failure (28% v 0%) and alanine aminotransferase peaks as compared with those of patients with an HBeAg+ donor. Liver failure was not observed in anti-HBs+ recipients. The use of HBsAg+ donors, particularly if anti-HBe+, increases the risk of severe liver disease in BMT recipients. Anti-HBs positivity may prevent severe liver damage.

HBV感染者因没有正常的抗HBV免疫功能，故不宜作BMT的供体。

3）Liang R, Lau GK, Kwong YL.Chemotherapy and bone marrow transplantation for cancer patients who are also chronic hepatitis B carriers: a review of the problem.J Clin Oncol 1999 Jan;17(1):394-8

In places where hepatitis B virus (HBV) infection is endemic, it is often necessary to give chemotherapy to or perform bone marrow transplantation for cancer patients who are also chronic HBV carriers. When standard chemotherapy was given to lymphoma patients, elevation of liver transaminases was observed in nearly half of those who were chronic HBV carriers. Ten percent of them became jaundiced, and the overall liver-related mortality was about 5%. There is currently no reliable way to predict the severity of HBV reactivation after chemotherapy. The risk is probably higher when the chemotherapy used is significantly immunosuppressive and the viral load in the liver is high. Different strategies have been used in an attempt to reduce the risk of HBV reactivation after chemotherapy, but they have not been very successful. Further studies will be required to determine the impact of newly available antiviral agents that are active against HBV. Recipients who are carriers of HBV or who receive hepatitis B surface antigen (HBsAg)-positive marrow are at increased risk of hepatitis B-related morbidity and mortality after bone marrow transplantation (BMT). There is evidence to suggest that prophylactic use of an active antiviral agent, such as famciclovir, may result in a significant decrease in the incidence and severity of HBV reactivation after BMT. Sustained serologic clearance of chronic HBV infection has also been reported in many HBsAg-positive marrow recipients receiving hepatitis B surface antibody-positive marrow from their allogeneic donors. There seems to be a transfer of both humoral and cellular immunity against HBV from donors to recipients. Further prospective studies are required to define the best approach to manage HBsAg-positive cancer patients receiving chemotherapy or BMT. It is recommended that all cancer patients be checked for their hepatitis B status before receiving chemotherapy or a bone marrow transplant, especially if they reside in or come from endemic areas of HBV infection.

HBV感染者因没有正常的抗HBV免疫功能，故不宜作BMT的供体，否则致受体HBV感染；但采用HBS AB阳性受体的骨髓或干细胞进行BMT则又使不少HBV感染者的HBV得以清除而治疗HBV感染。

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4）Ilan Y, Nagler A, Adler R, Tur-Kaspa R, Slavin S, Shouval D.Ablation of persistent hepatitis B by bone marrow transplantation from a hepatitis B-immune donor.Gastroenterology 1993 Jun;104(6):1818-21 Chronic hepatitis B virus (HBV) infection is still a major cause of liver disease for which no definite therapy is available. We describe here a hepatitis B surface antigen (HBsAg) carrier patient with active viral replication (HBV DNA positive) who was treated for leukemia by bone marrow transplantation (BMT) from an HBV immune donor. Following BMT from the antibody to hepatitis B core antigen (anti-HBc) positive/anti-HBs positive bone marrow donor, immune reconstitution of the recipient's bone marrow resulted in clearance of the circulating HBsAg, as well as HBV DNA. The patient acquired immunity against HBV, which lasted for more than 8 months posttransplantation. Therefore, this report provides evidence that adoptive transfer of specific immunity against HBV through allogeneic BMT may lead to clearance of persistent HBV infection. Furthermore, the data support the hypothesis that the HBsAg carrier state is most probably the result of an inefficient immune response against HBV, implying that clearance of HBV may be facilitated by adoptive cellular immunotherapy. 采用天然HBV免疫的供体进行BMT可治愈慢性HBV感染受体的HBV感染，因此细胞过继免疫疗法是清除HBV感染有力手段 5）Shouval D, Adler R, Ilan Y. Adoptive transfer of immunity to hepatitis B virus in mice by bone marrow transplantation from immune donors.Hepatology 1993 Jun;17(6):955-9 Recipients of allogeneic bone marrow transplantation are immunosuppressed as a result of their primary disease and by myeloablative therapy. Such patients are dependent on multiple blood products and are at risk for hepatitis B virus infection. Active immunization against hepatitis B in the immediate pre- and post-transplant periods is ineffective, presumably because of decreased T cell-dependent B-cell responses. This study was designed to evaluate, in a mouse model system, the transfer of immunity against hepatitis B to bone marrow transplant recipients through immunization of bone marrow donors against hepatitis B before transplantation. Bone marrow donor BALB/c mice were immunized with a recombinant hepatitis B vaccine. Seroconversion to HBs antibody occurred within 4 wk of primary immunization, and antibody levels in treated donor mice rose above 300 mIU/ml after a single booster injection. Bone marrow recipient mice, conditioned by sublethal irradiation, were injected intravenously with bone marrow cells obtained from syngeneic HBs antibody-positive immune donors. Antibody was detected in 10% of bone marrow recipients within 30 days of transplantation and in 56% 1 mo after a booster injection that led to a secondary rise in HBs antibody. Adoptive transfer of immunity to hepatitis B also occurred after transplantation of T cell-depleted bone marrow cells from hepatitis B-immune donors, albeit at a lower HBs antibody level. These results indicate that immunity to hepatitis B can be transferred in mice by bone marrow transplantation from hepatitis B-immune donors to immunosuppressed recipients.(ABSTRACT TRUNCATED AT 250 WORDS) 采用HBV免疫的供体/小鼠进行BMT细胞过继免疫，可致受体的抗HBS产生增加，且去除T细胞亦有一定作用，说明DC/APC和T细胞均、有益于抗HBS抗体的产生，说明DC--TH1-BLC轴对于抗病毒免疫体液免疫产生很重要 6）Ilan Y, Nagler A, Adler R, Naparstek E, Or R, Slavin S, Brautbar C, Shouval D. Adoptive transfer of immunity to hepatitis B virus after T cell-depleted allogeneic bone marrow transplantation. Hepatology 1993 Aug;18(2):246-52 Recipients of allogeneic bone marrow transplantation are pancytopenic for several weeks and immunosuppressed for many months as a result of myeloablative therapy required to eliminate the basic disease and to prevent allograft rejection. After bone marrow transplantation, these patients remain profoundly immunosuppressed by the chemotherapy and immunotherapy used as prophylaxis against graft-vs.-host disease, treatment of established disease or both. These patients are usually dependent on multiple blood products and are therefore at risk for hepatitis B virus infection, which may run a fulminant course. Active immunization against hepatitis B virus in the immediate pre-bone marrow transplantation and post-bone marrow transplantation periods was found to be ineffective, probably because of the absence of T cell-dependent B-cell responses, which persists for approximately 1 yr after bone marrow transplantation. We studied adoptive transfer of immunity to hepatitis B virus through bone marrow transplantation in two populations of patients. The first group (A) consisted of 12 pairs of BMT donors and recipients, in which all bone marrow donors were positive for antibodies to HBc and HBs as a result of previously acquired hepatitis B virus infection and resolution; all recipients were negative to antibodies to HBc and HBs. The second group (B) consisted of eight pairs of donors and recipients in which all the donors were actively immunized against hepatitis B virus before bone marrow transplantation; all recipients were negative for all hepatitis B virus markers. All bone marrow transplantation recipients were monitored for antibodies to hepatitis B virus antigens.(ABSTRACT TRUNCATED AT 250 WORDS) 采用HBV免疫的供体/小鼠进行BMT细胞过继免疫，可致受体的抗HBS产生增加，且去除T细胞亦有一定作用，说明DC/APC和T细胞均、有益于抗HBS抗体的产生，说明DC--TH1-BLC轴对于抗病毒免疫体液免疫产生很重要 7）Ilan Y, Nagler A, Shouval D, Ackerstein A, Or R, Kapelushnik J, Adler R, Slavin S. Development of antibodies to hepatitis B virus surface antigen in bone marrow transplant recipient following treatment with peripheral blood lymphocytes from immunized donors.Clin Exp Immunol 1994 Aug;97(2):299-302 Bone marrow transplantation (BMT) recipients are immunosuppressed and are at risk for contracting severe infections. Recently, adoptive transfer of immunity against hepatitis B virus (HBV) was documented in BMT recipients receiving bone marrow from 'naturally' HBV-infected individuals who recovered spontaneously, or those transplanted with bone marrow cells obtained from actively immunized donors. Furthermore, reconstitution of the immune system in a BMT recipient who was a hepatitis surface antigen (HBsAg)+/HBV DNA+ carrier with HBV immune bone marrow cells led to clearance of the replicating virus, presumably through adoptive cell-mediated immunotherapy. We report three cases of induction of immunity to HBV by selective adoptive transfer by i.v. injection of peripheral blood lymphocytes (PBL) obtained from BMT donors who were actively immunized against HBV after harvesting of bone marrow. All three BMT recipients developed anti-HBs antibodies. In one BMT case in whom antibodies to HBsAg developed following adoptive transfer of immune PBL, a mild booster effect was documented in the BMT recipient upon immunization with a recombinant hepatitis B vaccine. The two remaining patients lost their antibodies to HBsAg in association with relapse of leukaemia. This immune manipulation may open the door to evaluation of adoptive transfer of immunity to HBV through selective transplantation of HBV immune lymphocytes in selected patients such as those with persistent HBV infection, as well as liver transplant recipients who require protection of the graft against HBV re-infection. HBV感染受体选择性过继已采用HBV疫苗主动免疫的供者/供体的外周血淋巴细胞（CD4+？？？？）便可成功地治疗受体的HBV感染并产生抗HBV抗体，且因免疫不同功能状态而产生抗HBS抗体与否及消失与否，因此对受体的CD4+治疗或过继已采用HBV疫苗主动免疫的供者/供体的外周血淋巴细胞中CD4+可能是一法，而HBV疫苗尤常规疫苗似可作治疗性疫苗用？？？？ 8）Shouval D, Ilan Y.Immunization against hepatitis B through adoptive transfer of immunity. Intervirology 1995;38(1-2):41-6 Clearance of hepatitis B virus (HBV) infection requires an effective T-cell-dependent humoral response that is often defective in HBV carriers and in immunosuppressed patients. We have shown in mice and humans that bone marrow (BM)-derived memory cells, capable of producing antibodies to the HBV envelope and nucleocapsid antigens, are transferable from BM donors (BMD) to their recipients. BMD BALB/c mice were immunized with recombinant HBV surface antigen (HBsAg), and BM from anti-HBs-positive donors was transplanted to irradiated recipient mice, who seroconverted to anti-HBs within 30 days of bone marrow transplantation (BMT), and responded to booster vaccination. In a similar manner, 19/26 human BM recipients, who received their HLA-matched BM from BMDs immunized once with HBsAg, seroconverted within several weeks after BMT. Antibodies to observHBsAg were alsoed in 3 recipients of peripheral blood lymphocytes (PBL) obtained from HLA-matched immunized human donors. Finally, clearance of HBsAg and HBV DNA was observed in an HBsAg carrier with leukemia who received BMT from his HLA-matched anti-HBc+/anti-HBs+ brother. These results indicate that adoptive transfer of immunity to HBV may be achieved through immunization of BM or PBL donors against HBV. 采用过继已采用HBV疫苗主动免疫的供者/供体的外周血淋巴细胞或者接受天然HBV免疫的供体进行BMT,均致HBV感染者的HBS AG清除和抗HBS抗体产生 9）Nagler A, Ilan Y, Adler R, Or R, Naparstek E, Shouval D, Slavin S. Successful immunization of autologous bone marrow transplantation recipients against hepatitis B virus by active vaccination.Bone Marrow Transplant 1995 Mar;15(3):475-8 Patients undergoing autologous bone marrow transplantation (BMT) are severely immunosuppressed. These patients are exposed to various infections agents due to delayed and efficient reconstitution of their immune system. Forty-eight patients with hemato-oncological malignancies were immunized against hepatitis B virus (HBV) following autologous BMT. Twenty one were vaccinated more than 10 days before BMT, 17 on days 1-9 before and 10 day after BMT. Thirty three patients (68.7%) seroconverted within 40 days after autologous BMT after receiving one dose of the vaccine before autologous BMT with a relatively low level of anti-HBs, whereas in 11 no anti-HBV antibodies could be detected. Nineteen patients remained seropositive but in 11 the seroconversion was only transient no correlation was found between permanent or transient seroconversion and basic disease, conditioning regimens, post-transplant therapy, immunotherapy and day of vaccination in relation to autologous and day of vaccination in relation to autologous BMT. Active HBV immunization of patients with malignancy undergoing autologous BMT is feasible and levels of antibodies, although low, are above the conventional protective titers. Therefore active immunization of some patients may reduce hepatitis-related complications in the setting of autologous BMT. 自体BMT前主动HBV免疫接种有效于产生抗HBS抗体 10）Nagler A, Ilan Y, Varadi G, Kapelushnik J, Or R. In vivo CAMPATH-1 followed by T cell-depleted bone marrow transplantation: a potential new mode of therapy for hepatitis-associated severe aplastic anemia (SAA). Bone Marrow Transplant 1996 Aug;18(2):475-8 Bone marrow transplantation (BMT) has been previously reported as a successful mode of treatment for hepatitis B and associated severe aplastic anemia (SAA). Non-A, non-B, non-C hepatitis is one of the causes of SAA. The etiology of SAA caused by non-A, non-B, non-C hepatitis is unknown. There is evidence that the immune response and, specifically, T cells and monocytes have a major role in both HCV- and HBV-induced liver damage. The liver damage caused by non-A, non-B, non-C hepatitis may be associated with similar mechanisms. We describe an 8-year-old girl who developed SAA post-non-A, non-B, non-C hepatitis infection. She was treated by in vivo CAMPATH-1G antibodies followed by T cell depleted HLA-matched BMT and cyclosporin A, resulting in gradual improvement and almost normalization of liver function. We suggest that treatment with CAMPATH-1G followed by T cell-depleted BMT and cyclosporin A could be a novel mode of therapy for viral non-A, non-B, non-C hepatitis-induced liver damage and associated SAA. 连最简单的非病原特异性BMT细胞过继免疫便可治NANBNC性肝炎呢 11）Lau GK, Lok AS, Liang RH, Lai CL, Chiu EK, Lau YL, Lam SK.Clearance of hepatitis B surface antigen after bone marrow transplantation: role of adoptive immunity transfer. Hepatology 1997 Jun;25(6):1497-501 Adoptive immunity transfer has been reported to be effective in clearing chronic hepatitis B virus (HBV) infection. Two hundred twenty-six patients who received allogeneic bone marrow transplantation (BMT) between May 1990 and September 1995 were screened for hepatitis B markers. Twenty-one patients were hepatitis B surface antigen (HBsAg) positive before BMT. The median follow-up period was 20 months (range, 2-59 months). Two of these patients had sustained clearance of HBV infection after transplantation. Both patients were hepatitis B e antigen (HBeAg)-negative, hepatitis B e antibody (anti-HBe)-positive, and serum HBV DNA-negative (by dot-blot hybridization) before BMT. Both had a flare in the serum alanine transaminase (ALT) level around the time of HBsAg clearance. Sustained clearance of HBsAg was observed in 2 of the 5 patients who received hepatitis B surface antibody (anti-HBs)-positive marrow but in none of the 16 patients who received anti-HBs-negative marrow (P < .05). One additional patient who received anti-HBs-positive marrow had transient HBsAg seroconversion. Among the 18 patients who remained persistently HBsAg-positive after BMT, 3 had HBeAg seroconversion and 3 had reversion to HBeAg positivity. In this study, we found a significant association between clearance of HBV infection and anti-HBs-positive bone marrow donors. Adoptive immunity transfer is effective in clearing HBV from patients with chronic HBV infection. BMT中，HBV清除与 anti-HBs阳性BMT供体有关，因此采用天然HBV免疫的供体进行BMT通过过继免疫而治愈HBV感染 12）Ilan Y, Gabay E, Amit G, Feder R, Galun E, Adler R, Shouval D. Suppression of human hepatoma in mice through adoptive transfer of immunity to the hepatitis B surface antigen. J Hepatol 1997 Jul;27(1):170-5 BACKGROUND/AIMS: Adoptive transfer of immunity against hepatitis B surface antigen (HBsAg) has previously been shown to occur in mice and humans through transplantation of bone marrow cells from donors immunized against HBsAg (anti-HBs) to non-immune recipients. In the present study we evaluated the effect of adoptive transfer of immunity to HBsAg on the growth of HbsAg-secreting hepatocellular carcinoma (HCC) xenografts in athymic mice. METHODS: Immunocompetent mice were immunized with recombinant HBsAg. Bone marrow cells from anti-HBs+ mice were injected intravenously to irradiated athymic Balb/c mice which had been previously transplanted subcutaneously with Hep3B human hepatoma cells. Treatment groups included mice receiving bone marrow transplantation from HBV-immunized (anti-HBs positive) and non-immunized (anti-HBs negative) donors. RESULTS: At 9 weeks post bone marrow transplantation, tumor volume and serum alpha-fetoprotein levels in athymic mice receiving HBV-immune bone marrow cells were 11.5 mm3 and 363 ng/ml, respectively, as compared to 1579 mm3 and 19,000 ng/ml, in recipients of non-immune bone marrow transplantation (p<0.005). T-cell depletion of antiHBs+ immune bone marrow prior to transplantation decreased the anti-tumor effect but did not abolish it. A mild nonspecific, bone marrow-derived, graft versus tumor effect was observed in mice transplanted with human hepatoma cells that do not express HBsAg. CONCLUSIONS: Adoptive transfer of immunity to HBV facilitates suppression of experimental human HCC expressing HBsAg. This effect is the result of a combination of specific anti-viral surface antigen effect and a nonspecific graft versus tumor effect. 采用HBV免疫的供体进行BMT通过过继免疫而控制HBV感染性肝癌呢

天狼星

13）Lau GK, Liang R, Lee CK, Yuen ST, Hou J, Lim WL, Williams R. Clearance of persistent hepatitis B virus infection in Chinese bone marrow transplant recipients whose donors were anti-hepatitis B core- and anti-hepatitis B surface antibody-positive. J Infect Dis 1998 Dec;178(6):1585-91

Thirteen hepatitis B surface antigen-positive Chinese patients who received hepatitis B surface antibody-positive marrow (hepatitis B core antibody-positive or -negative: 6 and 7, respectively) via allogeneic bone marrow transplantation (BMT) were studied. After BMT, 4 recipients had serologic clearance of hepatitis B surface antigen from hepatitis B core antibody-positive marrow, but none of the recipients of hepatitis B core antibody-negative marrow had serologic clearance (P=.02). There was no significant difference in the donors' hepatitis B surface antibody titer before BMT for patients with or without serologic clearance of hepatitis B surface antigen (2255.2+/-4244.0 vs. 854.2+/-2306.7 mIU/mL; P=not significant). Adoptive immunity clearance of hepatitis B surface antigen was favored by hepatitis B core antibody positive-donor marrow and was not related to donor pre-BMT hepatitis B surface antibody titer.

采用天然HBV免疫的供体进行BMT通过过继免疫而治愈HBV感染，而且发现HBV感染治治愈与供体的抗HBC抗体有关而与抗HBS抗体无关。说明HBC AG的免疫反应有利于治疗HBV感染而HBS AG的免疫反应仅有利于防止HBV再感染

14）Lau GK, Yuen ST, Au WY, Wu PC, Liang R. Histological changes during clearance of chronic hepatitis B virus infection by adoptive immunity transfer. J Gastroenterol Hepatol 1999 Mar;14(3):262-8

BACKGROUND: Serological clearance of hepatitis B surface antigen (HBsAg) has been described after reception of hepatitis B surface antibody positive marrow, via allogeneic bone marrow transplantation (BMT). Histological changes during the clearance of HBsAg are unknown. METHODS AND RESULTS: We described two chronic hepatitis B carriers (both hepatitis B e antigen negative), who cleared HBsAg after allogeneic bone marrow transplantation. Both received hepatitis B surface and core antibody positive human leucocyte antigen identical donors' marrow and had serological clearance of HBsAg 15 and 7 weeks after allogeneic BMT, respectively. Both events were preceded by hepatic flare. Both patients were also treated with famciclovir for the prevention of hepatitis B reactivation after BMT. Histological examination during the flare showed only mild necroinflammatory activity with multiple foci of confluent necrosis, associated with moderate lymphocytic infiltration. The majority of these lymphocytes were cluster of differentiation (CD) 8 positive. Using immunohistochemistry, there was no detectable hepatic expression of hepatitis B core antigen. However, HBsAg was positive, mainly in the area of confluent necrosis. Using in situ hybridization, hepatitis B virus (HBV) DNA was detected in the nucleus of 5% of hepatocytes, but not in the cytoplasm. CONCLUSIONS: At their last follow up, 22 and 16 months after BMT, the serum of both patients remained HBsAg negative, hepatitis B surface antibody positive and HBV-DNA negative by branched DNA assay.

采用天然HBV免疫的供体进行BMT通过过继免疫而治愈HBV感染，但血清HBV指标转阴而肝细胞核内仍有极微量的HBVDNA存在，此少量HBV DNA只有在机体免疫功能明显下降时才又发病，这又解释了为什么抗HBS抗体阳性血液病/白血病病人进行BMT后因防排斥反应而使用免疫抑制剂后致体内仅存的极微量的HBV病毒复燃而大量复制，故诱发肝炎发作甚至重症肝炎

15）Ilan Y, Nagler A, Zeira E, Adler R, Slavin S, Shouval D.Maintenance of immune memory to the hepatitis B envelope protein following adoptive transfer of immunity in bone marrow transplant recipients. Bone Marrow Transplant 2000 Sep;26(6):633-8

Adoptive transfer of immunity against hepatitis B surface antigen (HBsAg) has been documented in mice and humans. In the present study, we report long-term follow-up of antibodies to HBsAg in humans who received allogeneic bone marrow transplantation (BMT) from donors immunized with HBsAg. BM donors were immunized with recombinant HBsAg. BM or PB cells were transplanted to HLA matched recipients. Recipients were followed for anti-HBs seroconversion. Control groups included non-immunized or rHBsAg immunized healthy adults as well as individuals that had had hepatitis B and recovered spontaneously. PBLs were stimulated in vitro with rHBsAg and stimulation was expressed as stimulation index. Adoptive transfer of immunity to HBsAg was initially documented in 12 recipients of BM from anti-HBc+/anti-HBs+ donors. An almost 4 year follow-up showed detectable protective anti-HBs levels (>10 mIU/ml) in 50% of patients. Immunity to HBV was also documented in 22/35 BMT recipients (62%), who received their bone marrow from actively immunized donors. In 7/9 of these BMT recipients, anti-HBs antibodies levels were documented 25 months following BMT. In 6/8 (75%) of patients who received only PBLs from HBV immune donors, adoptive transfer of immunity to HBV, and seroconversion to HBsAg+, were documented within 2 months of i.v. injection. Evidence for specific cellular immune response with increased SIs was documented for healthy vaccinees, and BMT recipients, and in none of the healthy non-vaccinated controls. These results suggest that adoptive transfer of immunity to HBV is a useful method for providing long-lasting protection for BM recipients.

采用过继已采用HBV疫苗主动免疫的供者/供体的外周血淋巴细胞或者接受天然HBV免疫的供体进行BMT,均致受体抗HBS抗体产生

15） Lau GK, Suri D, Liang R, Rigopoulou EI, Thomas MG, Mullerova I, Nanji A, Yuen ST, Williams R, Naoumov NV.Resolution of chronic hepatitis B and anti-HBs seroconversion in humans by adoptive transfer of immunity to hepatitis B core antigen.Gastroenterology 2002 Mar;122(3):614-24

BACKGROUND & AIMS: Impaired T-cell reactivity is believed to be the dominant cause of chronic hepatitis B virus (HBV) infection. We characterized HBV-specific T-cell responses in chronic hepatitis B surface antigen carriers who received bone marrow from HLA-identical donors with natural immunity to HBV and seroconverted to antibody to hepatitis B surface antigen. METHODS: T-cell reactivity to HBV antigens and peptides was assessed in a proliferation assay, the frequency of HBV core- and surface-specific T cells was quantified directly by ELISPOT assays, and T-cell subsets were analyzed by flow cytometry. RESULTS: CD4+ T-cell reactivity to HBV core was common in bone marrow donors and the corresponding recipients after hepatitis B surface antigen clearance, whereas none reacted to surface, pre-S1, or pre-S2 antigens. Furthermore, CD4+ T cells from donor/recipient pairs recognized similar epitopes on hepatitis B core antigen; using polymerase chain reaction for the Y chromosome, the recipients' CD4+ T lymphocytes were confirmed to be of donor origin. The frequency of core-specific CD4+ and CD8+ T cells was several-fold higher than those specific for surface antigen. CONCLUSIONS: This study provides the first evidence in humans that transfer of hepatitis B core antigen-reactive T cells is associated with resolution of chronic HBV infection. Therapeutic immunization with HBV core gene or protein deserves further investigation in patients with chronic hepatitis B.

接受天然HBV免疫的供体进行BMT致HBV感染者的HBS AG清除，其HBV清除作用与HBC AG特异性TH/CD4T细胞从天然HBV免疫的供体过继给HBV感染的受体有密切关系，即天然HBV免疫的供体的HBC AG特异性TH/CD4T细胞在受体内长期存在于受者体内并发挥其抗HBV免疫的免疫调控作用


战胜乙肝 小山制作 2002-04-17上传

天狼星

骨髓干细胞在大鼠肝纤维化形成环境中的分化
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　　　　来源：中华肝脏病杂志

  
展玉涛  魏来  陈红松  丛旭  费然  王宇
【摘要】  目的  研究骨髓干细胞在肝纤维化形成环境中向肝细胞定向分化。 方法  采用四氯化碳皮下注射法诱导大鼠肝纤维化，应用流式细胞仪分选富集Thy+CD3-CD45RA-的骨髓干细胞，采用红色荧光染料PKH26-GL对其标记后进行自体移植，6周后通过免疫组织化学方法检测大鼠肝组织白蛋白、ck8、α-平滑肌肌动蛋白表达。 结果  PKH26-GL标记的细胞在纤维化肝脏中表达白蛋白和ck8，占肝细胞总数的(0.17±0.02)%；未见表达α-平滑肌肌动蛋白。 结论  骨髓干细胞在肝纤维化形成环境中可以向肝细胞定向分化，不向肌成纤维样细胞分化。
【关键词】  肝纤维化； 干细胞； 大鼠； 肝细胞

Differentiation of bone marrow stem cells in rat hepatic fibrogenesis environment  ZHAN Yu-tao, WEI Lai, CHEN Hong-song, CONG Xu, FEI Ran, WANG Yu. Hepatology Institute, People抯 Hospital, Peking University, Beijing 100044, China
【Abstract】    Objective    To observe the differentiation of bone marrow stem cells in rat hepatic fibrogenesis environment into hepatocytes. Methods    Rat hepatic fibrosis was induced by subcutaneous injection of CCl4. Bone marrow stem cells with Thy positive, CD3 and CD45RA negative were enriched from the bone marrow by fluorescence-activated cell sorting. The bone marrow stem cells were labeled with PKH26-GL, and then autotransplanted. After six weeks, albumin, ck8 and α-smooth  muscle actin expression were determined by immunocytochemistry. Results    The PKH26-GL labeled cells expressed albumin and ck8, but did not express α-smooth muscle actin in hepatic fibrogenesis environment. Conclusions    Bone marrow stem cells in hepatic fibrogenesis environment can differentiate into hepatocytes, but can抰 differentiate into myofibroblasts.
【Key words】    Hepatic fibrosis;  Stem cells;  Rats;  Hepatocytes
　　目前认为，肝脏与其它器官一样由成熟细胞、祖细胞和干细胞三个层次的细胞组成，分别为：(1)成熟肝细胞；(2)原始的决定组织特异性的干细胞，位于成熟肝脏的终末胆管即Hering管；(3)多潜能干细胞，来源于血液循环中的骨髓干细胞[1]。人们对成熟的肝细胞已有了较为深入的研究和认识，对肝脏祖细胞的存在及向肝细胞、胆管细胞分化的功能已成共识，但对骨髓干细胞在肝脏中的作用认识较少。近年来，有报道骨髓干细胞在正常肝脏环境中能分化为肝细胞[2]，但有关骨髓干细胞在肝纤维化形成环境中分化的研究鲜见报道。采用四氯化碳皮下注射方法制备大鼠肝纤维化模型并通过自体移植骨髓干细胞研究骨髓干细胞在肝纤维化形成环境中向肝细胞的定向分化。
材料与方法
一、实验动物
　　1. 雄性SD大鼠，体重为160～180g，购自中国医学科学院实验动物中心，在北京大学人民医院动物中心普通饲料喂养，自由进食。
　　2. 实验分组：(1)正常组：6只，用于肝纤维化对照；(2)实验组：6只，应用四氯化碳制备肝纤维化模型并进行自体骨髓干细胞移植。
二、主要试剂
　　红细胞裂解液，藻红蛋白标记的小鼠抗大鼠CD3抗体，PE标记的小鼠抗大鼠CD45RA抗体均为美国Becton Dickinson公司产品；异硫氰酸荧光素标记的小鼠抗大鼠Thy-1.1抗体是美国BD.Pharmingen公司产品；RPMI 1640培养基，美国Gibco公司产品；PKH26-GL，异硫氰酸荧光素标记的α-平滑肌肌动蛋白（α-smooth muscle actin，α-SMA）抗体均为美国Sigma公司产品；四氯化碳购自北京化学试剂公司；橄榄油购自北京芳草医药化工；白蛋白抗体和细胞角蛋白抗体均为美国Dako公司产品。
三、肝纤维化模型的制备
　　按3ml/kg皮下注射40％的四氯化碳溶液，3d一次，共42d。首次剂量为5ml/kg。
四、骨髓干细胞的分离、体外标记和自体移植
　　从模型大鼠一侧胫骨中提取骨髓细胞，红细胞裂解液去除红细胞后通过流式细胞仪分选Thy+CD3-CD45RA－细胞来富集骨髓干细胞；采用PKH26-GL标记所分离的骨髓干细胞，标记方法按说明书操作，所用PKH26-GL的浓度为10μmol/L。骨髓肝细胞标记后，采用腹部正中切口＋右侧横切口暴露大鼠肝脏门静脉，将PKH26-GL标记的骨髓干细胞进行自体移植，经门静脉给予300μl骨髓干细胞悬液(含细胞为1×106个)，缝合切口。
五、标本收集、保存及检测
　　骨髓干细胞移植6周后处死大鼠，迅速取肝组织，置液氮中速冻，然后置－80℃冰箱中保存，待组织学检查。肝组织学检测包括苦味酸酸性复红法染色，白蛋白、细胞角蛋白及α-SMA免疫组织化学检查。
结    果
一、骨髓干细胞的富集
　　红细胞裂解液去除骨髓细胞中的红细胞后经流式细胞仪分选获得Thy+CD3-CD45RA-细胞群，该细胞约占骨髓有核细胞的2.1%。
二、骨髓干细胞的PKH26-GL染色
　　应用10μmol/L PKH26-GL对分离的骨髓干细胞即Thy+CD3-CD45RA-细胞进行标记，流式细胞仪分析其标记率约为(95±3)％，且标记的细胞在荧光显微镜下显示了较强的红色荧光，提示PKH26－GL适合标记骨髓干细胞。
三、肝纤维化形成
　　VG染色结果表明，正常大鼠肝脏肝板以中央静脉为中心呈条索状向四周放射样排列，板间有不规则肝窦，肝小叶内网状纤维支架完整，分布规律，无明显的胶原纤维存在。实验组大鼠于四氯化碳皮下注射6周肝纤维化形成，肝小叶结构破坏，纤维结缔增生，假小叶形成（图1）。
四、骨髓干细胞在纤维化肝组织中分化为表达白蛋白和ck8的肝细胞
　　PKH26-GL在波长为551nm的激发光作用下发出红色荧光，在共聚焦显微镜下发现，实验组大鼠肝组织切片中可见散在的红色荧光标记，提示体外PKH26-GL标记的骨髓细胞能移居肝脏（图2a）。FITC在波长为494nm的激发光作用下发出绿色荧光，检测肝细胞白蛋白表达的抗体为FITC间接标记抗体，白蛋白在肝细胞中广泛表达（图2b）。红色荧光与绿色荧光共聚焦叠合后呈黄色（图2c），黄色细胞来源于体外PKH26-GL标记的骨髓细胞，并且表达白蛋白。ck8免疫组织化学结果与白蛋白相似（照片相似，未再提供），这种PKH26-GL标记且表达白蛋白、ck8的细胞约占肝细胞总数的(0.17±0.02)%，结果表明骨髓干细胞在肝纤维化形成环境中能分化为肝细胞。
五、骨髓干细胞在纤维化肝组织中不表达α-SMA
　　实验结果表明，实验组大鼠肝组织中部分细胞表达α-SMA，这些细胞主要分布于纤维间隔内。但共聚焦显微镜下未发现PKH26-GL阳性细胞表达α-SMA，提示骨髓干细胞在肝纤维化形成环境中不向肌成纤维样细胞分化。
讨    论
　　Theise等[2]将正常雄性小鼠骨髓移植到正常雌性小鼠体内，应用荧光原位杂交方法检查雌性小鼠肝脏细胞Y染色体，结果发现雌性小鼠肝脏的部分肝细胞表达Y染色体，提示骨髓干细胞在正常肝脏环境中能分化为肝细胞。进一步研究发现，人骨髓干细胞在正常肝脏中也能分化为肝细胞[3]。Petersen等[4]将雄性大鼠骨髓细胞移植到肝损伤且肝细胞增殖被抑制模型的雌性大鼠体内，发现该模型雌性大鼠肝脏中部分细胞表达Y染色体，且Y染色体阳性细胞亦表达成熟肝细胞，提示骨髓干细胞在肝损伤且肝细胞增殖被抑制的肝脏中能分化为肝细胞。Lagasse等[5]将正常小鼠骨髓干细胞移植到延胡索酰已酰乙酸羟化酶基因缺陷（即致死性遗传性高酪氨酸血症）模型小鼠体内，结果证实骨髓干细胞在该模型小鼠肝脏中能分化为肝细胞。上述结果提示骨髓干细胞不仅在正常肝脏环境中能分化为肝细胞，而且在某些疾病肝脏环境中也能分化为肝细胞。我们从大鼠胫骨中提取骨髓细胞，通过流式细胞仪富集骨髓干细胞，经体外PKH26-GL标记后进行自体移植，采用间接荧光免疫组织化学方法检查肝细胞特异性标志－白蛋白和ck8，发现体外标记的骨髓干细胞在肝纤维化形成环境中表达白蛋白和ck8，提示移植的骨髓干细胞在肝纤维化形成的微环境中能够分化为肝细胞。肝纤维化的主要病理特征是大量细胞外基质在肝组织中沉积，在肝纤维化形成过程中肝星状细胞活化转化为肌成纤维样细胞，肌成纤维样细胞是肝纤维化细胞外基质的主要来源细胞[6，7]。α-SMA是一种肌动蛋白，具有收缩功能，主要存在于血管平滑肌细胞中，但在许多肌成纤维样细胞中也表达，正常情况下肝星状细胞处于“静止状态”，不表达α-SMA，但肝纤维化形成过程中转化后的肌成纤维样细胞表达α-SMA[8，9]。目前，α-SMA已成为肝纤维化形成过程中肌成纤维样细胞的检测标志。最近资料表明，神经脊干细胞能分化为肌成纤维样细胞[10，11]，Efendy等[12]通过体内实验研究也发现，小鼠骨髓来源的细胞在腹腔内形成肌成纤维样细胞。我们通过免疫组织化学方法未发现体外标记的骨髓干细胞在肝纤维化形成的肝脏中表达α-SMA，结果提示移植的骨髓干细胞在肝纤维化形成过程中不分化为肌成纤维样细胞。
　　研究结果初步表明，移植的自体骨髓干细胞在肝纤维化形成过程中能够分化为肝细胞，未发现向肌成纤维样细胞分化。结果提示，通过骨髓干细胞移植可能有助于补充肝纤维化形成过程中不断丧失的肝细胞，而不会使肝纤维化形成的关键细胞——肌成纤维样细胞大量增加，因此干细胞移植可能对治疗慢性肝炎、肝纤维化是有益的，为进一步研究干细胞治疗慢性肝病提供了实验依据。
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（收稿日期：2002-10-21）
（本文编辑：袁平戈）

基金项目：国家863计划（2001AA216031）；2002年度《中华肝脏病杂志》中青年肝病科研基金
作者单位：100044 北京大学人民医院肝病研究所

基督山伯爵

真的这样吗，那乙肝不是都就有救了，感谢上帝！

北非

呵呵！但愿这个课题早点做出来！只知道干细胞移植可治疗血癌！

dulac

快快研究啊！！！
到时候我一定捐献我的干细胞！