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标题: Annual Rate and Predictors of HBeAg, HBV DNA and HBsAg Seroclearance [打印本页]

作者: StephenW 时间: 2011-8-20 17:07 标题: Annual Rate and Predictors of HBeAg, HBV DNA and HBsAg Seroclearance

本帖最后由 StephenW 于 2011-8-20 17:10 编辑

This is an extract from the following paper. The complete paper is available at:
http://www.medscape.com/viewarticle/741368

From Journal of Gastroenterology and Hepatology
Natural History of Chronic Hepatitis B REVEALed

Chien-Jen Chen; Hwai-I Yang

Authors and Disclosures

Annual Rate and Predictors of HBeAg, HBV DNA and HBsAg Seroclearance

Seroclearance of HBeAg, HBV DNA, and HBsAg are important clinical outcomes for chronic hepatitis B treatment trials. Few studies have explored the incidence and determinants of spontaneous seroclearance using a long-term follow-up study. The annual seroclearance rates of HBeAg, HBV DNA and HBsAg have been estimated, respectively, for 439 HBeAg-seropositive participants with serum HBV DNA level ≥ 10 000 copies/mL, 1289 participants with serum HBV DNA level ≥ 10 000 copies/mL at enrollment, and 3087 HBsAg-seropositives in REVEAL-HBV study.[27–30] The annual seroclearance rate was 5.92% for HBeAg, 1.97% for HBV DNA, and 2.26% for HBsAg. The annual HBeAg seroclearance rate for HBeAg-seropositive participants who had serum HBV DNA levels ≥ 100 000 000 copies/mL was 4.44%.[28,29] The annual HBV DNA seroclearance rate after the seroclearance of HBeAg was 3.20%.[27] The annual HBsAg seroclearance rate after the seroclearance of HBV DNA was around 6%. In other words, the cumulative incidence of HBsAg seroclearance at 60 and 100 months after serum HBV-DNA level decreased to undetectable was 25.8% and 51.3%, respectively.[30]

Significantly higher HBeAg seroclearance rates were observed for female gender, elevated serum ALT level at entry (≥ 45 vs < 45 IU), low serum HBV DNA level (< 100 000 vs≥ 100 000 copies/mL), HBV genotype B/B + C (vs genotype C), and HBV precore G1896A mutant (vs wild type). The predictors of seroclearance of HBV DNA included low serum HBV DNA level (< 100 000 copies/mL) and central obesity (waist circumference > 90 cm in men and > 80 cm in women). The HBsAg seroclearance was significantly associated with increasing age, low serum HBV DNA level (< 100 000 vs≥ 100 000 copies/mL), high body mass index (≥ 30 vs < 30 kg/m2) and ethnicity of mainland Chinese (vs ethnicity of Hakka and Fukkienese

作者: 侬是马甲 时间: 2011-8-20 18:35

连接好像有问题？

作者: 大哥是陆军 时间: 2011-8-20 19:11

翻译下

作者: StephenW 时间: 2011-8-20 19:13

侬是马甲发表于 2011-8-20 18:35
连接好像有问题？

我测试了，没有问题.

作者: 侬是马甲 时间: 2011-8-20 19:17

StephenW 发表于 2011-8-20 19:13
我测试了，没有问题.

需要注册

作者: StephenW 时间: 2011-8-20 19:28

回复大哥是陆军的帖子

胃肠病学和肝病学杂志
慢性乙型肝炎的自然史发现

陈建仁;杨怀我

作者及披露

发表于：2011年5月12日;胃肠肝胆病。 2011，26（4）:628 - 638。 © 2011布莱克韦尔出版
按年率计算和预测对HBeAg，HBV DNA和乙肝表面抗原血清消除

对HBeAg，HBV - DNA和HBsAg 血清消除慢性乙型肝炎的治疗试验的重要临床结局。很少有研究探讨自发seroclearance的发病率和使用一个长期的随访研究的决定因素。已估计，每年对HBeAg，HBV - DNA和HBsAg 血清消除率分别为439例HBeAg血清学阳性血清HBV DNA水平的参与者，≥10 000拷贝/毫升，1289参与者与血清HBV DNA水平≥10万拷贝/ ml，在入学和3087例HBsAg seropositives REVEAL - HBV的研究[27-30] 血清消除率每年5.92％e抗原，HBV - DNA为1.97％，和2.26％，乙肝表面抗原。 [27]每年e抗原HBeAg血清阳性的参与者曾血清HBV DNA水平≥100 000 000拷贝/ ml 血清消除率是4.44％[28,29]每年的乙肝病毒DNA后HBeAg的血清消除血清消除率是3.20％。每年的乙肝表面抗原后的HBV DNA 血清消除 seroclearance率约为6％。换句话说，乙肝表面抗原血清消除在60至100个月后血清HBV - DNA水平降低到检测不到的累积发病率是25.8％和51.3％，分别为[30]。

HBeAg的血清消除率明显高于女性，高架入口血清ALT水平（≥45 VS <45 IU），低血清HBV DNA水平（<100 000 VS≥100 000拷贝/毫升），观察HBV基因型B / B + C（与C型），和HBV前C区G1896A突变（与野生型）。 HBV - DNA 血清消除的预测低血清HBV DNA水平（<100 000拷贝/ mL）和中央肥胖（腰围> 90厘米的男性和女性80厘米）。乙肝表面抗原血清消除显着相关，与年龄的增加，低血清HBV DNA水平（<100 000 VS≥100 000拷贝/毫升），高体重指数（≥30与<30 kg/m2）和中国大陆的种族（种族VS客家和Fukkienese)

作者: 大哥是陆军 时间: 2011-8-20 19:35

在线翻译的理解不了

作者: alex1234 时间: 2011-8-21 20:21

high body mass index (≥ 30 vs < 30 kg/m2) ->那是超胖的人，一般有脂肪肝了

作者: StephenW 时间: 2011-8-21 20:52

本帖最后由 StephenW 于 2011-8-21 22:17 编辑

alex1234 发表于 2011-8-21 20:21
high body mass index (≥ 30 vs < 30 kg/m2) ->那是超胖的人，一般有脂肪肝了

I must agree this is strange, we need to read the full paper. Fatty liver may be associated with liver damage, but does it reduce chances of seroclearance of HbsAg?

作者: 把握当下 时间: 2011-8-21 22:16

e血清转换跟免疫、dna、基因型、是否变异有关：
alt高的比低的容易转(≥ 45 vs < 45 IU), dna低的比高的容易转
(< 100 000 vs≥ 100 000 copies/mL)，B/B + C基因型比c基因型容易转，前c区G1896A变异比野毒株容易转。

首先dna不转其他都是浮云
其次e要是比dna先转了更令人纠结：变异后抗病毒就像在黑暗的隧道里摸索前进，没有e定量照耀前路

作者: StephenW 时间: 2011-8-21 22:26

本帖最后由 StephenW 于 2011-8-21 22:27 编辑

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"变异后抗病毒就像在黑暗的隧道里摸索前进，没有e定量照耀前路"

很难说。在此之前，很多HBeAg -ve肝炎的人，不知道他们可能有活跃肝炎（ALT异常和高水平的HBVDNA）。我个人认为，e抗原- ve活跃性肝炎也可以治疗.

作者: 把握当下 时间: 2011-8-21 22:37

StephenW 发表于 2011-8-21 22:26
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"变异后抗病毒就像在黑暗的隧道里摸索前进，没有e定量照耀前路"

完全同意dna高，e阴性乙肝病人必须治疗也可以治疗

不过我的意思是这些人治疗的困难性和复发率相对较高（与dna高，e阳性病人相比）
吃核苷药物时，dna是病毒复制的唯一指标
此时e抗原定量不再具有意义（虽然e抗原已经转换，但实际上复制在dna未转阴之前并未停止，只是复制过程不再产生e抗原而已）

dna转阴后到底有没有低位反复（阴性，但是仍少量复制）不再有e抗原定量这个指标做参考，只剩下的s抗原定量，但是s抗原定量非常不适合作为dna转阴后的病情指标，因为s在很长时间都不会动（就像在黑暗的隧道里摸索前进）

作者: StephenW 时间: 2011-8-21 22:46

本帖最后由 StephenW 于 2011-8-21 22:47 编辑

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同意你的观点.
我的疑问是：这变异的病毒(不产生e抗原)，比野生型病毒的毒性更大吗？
[我不知道答案].

作者: 把握当下 时间: 2011-8-21 22:56

StephenW 发表于 2011-8-21 22:46
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同意你的观点.

我这样认为：
乙肝病毒的毒性主要是三个方面：
复制能力强弱：dna level
躲避药物能力强弱：耐药性，据说是p区变异
躲避免疫攻击能力强弱：c区免疫变异，例如小三阳dna却是强阳这种

我说的变异是最后一种
e抗原消失是因为免疫攻击产生的变异，变异之后复制能力减弱（所以小三阳dna强阳一般5次方左右，没大三阳7,8次方那么高），但是生存性变强（免疫认为没有e抗原就是没病，不干活了，只有等免疫什么时候能识别s抗原了肝炎才可能会急性暴发，否则一直处于小规模攻击病毒状态，alt不高，这种肝炎更隐蔽更容易长期发展成纤维化而不自知）

作者: springa 时间: 2011-8-21 23:14

2009欧洲肝脏研究学会（EASL）乙肝诊治指南系列
http://www.hbvhbv.com/forum/foru ... fromuid-521998.html

作者: StephenW 时间: 2011-8-21 23:25

本帖最后由 StephenW 于 2011-8-21 23:26 编辑

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"免疫认为没有e抗原就是没病，不干活了"

这一点，我不同意:
1. e抗原不是病毒粒子的一部分（Dane粒子）
2. 仍然有表面抗原和新的病毒粒子(hbvdna)

乙肝是非常复杂的，有很多东西，我们不知道.

作者: alex1234 时间: 2011-8-22 19:54

StephenW 发表于 2011-8-21 23:25
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"免疫认为没有e抗原就是没病，不干活了"

eAg和cAg是很相似的，至于eAg的作用，至今也不明白。

作者: 把握当下 时间: 2011-8-22 20:33

StephenW 发表于 2011-8-21 23:25
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"免疫认为没有e抗原就是没病，不干活了"

那句话只是我自己的通俗理解，很可能不准确，希望有一天能得到乙肝作用机理的通俗准确解释

我说免疫不干活不是说一点都不干：既然有s抗体就意味着免疫做了一点工作，只是不够而已

我的意思是说免疫的实际效果等于没干活：
1.s抗体太少完全无法中和s抗原，免疫在中和s抗原方面没有做很多工作（从效果来看）
2.虽然能识别e抗原，但dna变异之后复制时不再产生e抗原，免疫无需中和e抗原或杀死相关肝细胞；
3.关于免疫对dna的作用，具体我不太清楚，但是大三肝炎病人e抗原显著下降dna确变化不大的情况确实存在，这种情况下等于说免疫没有在杀死dna上做很多工作（从效果来看）

作者: StephenW 时间: 2011-8-22 20:54

本帖最后由 StephenW 于 2011-8-22 20:54 编辑

alex1234 发表于 2011-8-22 19:54
eAg和cAg是很相似的，至于eAg的作用，至今也不明白。

"eAg和cAg是很相似的，至于eAg的作用，至今也不明白。" - 我非常同意.

有一些科学家认为eAg帮助乙肝病毒逃避免疫系统. 例如，studyforhope：
"Core epitope vaccines, even particle vaccines, fail, because the core is free of class I epitopes with only one exception the 18 to 27 AA core protein epitope as was used in the classical Cytel vaccine. it failed, because in most chronic carrier of the HLA A2 type, this epitope gets mutated and inactive, so the T cells stimulated/produced by the vaccine target nothing that exists in the virus anymore. This is BTW the only class I epitope that evolution has left in the core protein, against which the virus is normally protected by the e-Antigen flooding, it is also the epitope that is typically responsible for the clearance in acute HBV.""Core epitope vaccines, even particle vaccines, fail, because the core is free of class I epitopes with only one exception the 18 to 27 AA core protein epitope as was used in the classical Cytel vaccine. it failed, because in most chronic carrier of the HLA A2 type, this epitope gets mutated and inactive, so the T cells stimulated/produced by the vaccine target nothing that exists in the virus anymore. This is BTW the only class I epitope that evolution has left in the core protein, against which the virus is normally protected by the e-Antigen flooding, it is also the epitope that is typically responsible for the clearance in acute HBV."

但我不明白为什eAg消失，然后eAb出现.

作者: StephenW 时间: 2011-8-22 21:09

本帖最后由 StephenW 于 2011-8-22 21:10 编辑

把握当下发表于 2011-8-22 20:33
那句话只是我自己的通俗理解，很可能不准确，希望有一天能得到乙肝作用机理的通俗准确解释

我说免疫不干 ...

感谢您的解释。我同意您所有的观点。我不明白eAb的用途。通常情况下，小
三阳(eAg- ve，eAb+ve)意味病毒复制低，为什么呢？

作者: 把握当下 时间: 2011-8-22 22:49

StephenW 发表于 2011-8-22 21:09
感谢您的解释。我同意您所有的观点。我不明白eAb的用途。通常情况下，小
三阳(eAg- ve，eAb+ve)意味病毒复 ...

我不明白eAb的用途。通常情况下，小三阳(eAg- ve，eAb+ve)意味病毒复制低，为什么呢？
-----------------
我的理解：
如果免疫反应比较充分+病毒量低（dna水平不高），这样免疫战斗力超过病毒复制能力，大三阳就能逐渐转为小三阳携带，这种小三阳就是复制低的，即“通常情况”

如果免疫反应没那么充分+病毒量高，或者虽然充分但是病毒量太高，那么免疫就打不赢病毒，病毒量大还造成病毒容易变异：逐渐使用不释放e抗原进行复制的方式，即变成小三阳
这种小三阳就是不太常见的病毒量复制“高”的，但也没大三阳高，因为这种小三阳变异病毒抗免疫能力变强之后复制能力变弱了

作者: StephenW 时间: 2011-8-23 19:04

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我在一本教科书，“Viral Hepatitis 3rd Edition 病毒性肝炎”, 看到一个“免疫耐受”的建议解释。

"In the neonate born to an HBV-infected mother, it has been suggested that HBeAg
crosses the placenta and induces tolerance. HBeAg may also have an immunomodulatory function duringinfection in adult life. Low molecular weight soluble proteins, such as HBeAg, induce a state of immune nonresponsiveness,
at the T-helper (Th) level. HBeAg-induced tolerance results in T-cell non-response to HBcAg,as well as HBeAg-derived epitopes, so that elimination
of HBV-infected cells does not occur."
在乙型肝炎病毒感染的母亲所生的新生儿，它一直建议，HBeAg 的通过胎盘和诱导耐受。 e抗原也可能在成年生活在感染过程中免疫调节功能。低分子量可溶性蛋白质，如e抗原，诱发免疫无反应状态，在辅助性T（TH）的水平。 e抗原诱导的T细胞的非反应HBcAg的，以及HBeAg衍生的抗原表位的宽容的结果，因此，消除 HBV感染的细胞不会发生。

作者: 把握当下 时间: 2011-8-23 22:21

StephenW 发表于 2011-8-23 19:04
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我在一本教科书，“Viral Hepatitis 3rd Edition 病毒性肝炎”, 看到一个“免疫耐受 ...

恩，这个解释我在论坛上也看到一个，我觉得跟你看的基本一致（有兴趣可以搜索一下）：

“在以前的博客文章中，我讲过，乙肝病毒本身对肝细胞没有直接的细胞损伤作用，肝细胞的损伤是由于人体对病毒产生的免疫反应引起的。HBV感染肝细胞后，产生大量抗原，如上面提到的表面抗原(HBsAg)，核心抗原(HBcAg)，这些抗原存在于肝细胞内或表面，激活人体的免疫功能，对感染了病毒的肝细胞进行攻击，结果导致肝细胞的损伤。e抗原（HBeAg）与核心抗原(HBcAg)的氨基酸序列几乎一致，蛋白质组成基本相同。所不同的是，HBeAg的比HBcAg多了几个氨基酸，蛋白分子略大。核心抗原（HBcAg）用于组装病毒的内衣壳，包装病毒的DNA，e抗原（HBeAg）产生后即分泌到肝细胞外，进入血液和分布全身其它地方。

　　为什么两个差不多的蛋白质，一个（HBcAg）用于组装病毒，一个（HBeAg）用于分泌到肝细胞外呢？

　　推测这是乙肝病毒逃避人体免疫攻击的一种手段。在乙肝病毒感染的早期，或胎儿在出生期或在子宫内接触到有病毒的血液时，乙肝病毒在肝细胞内合成的e抗原（HBeAg）并释放到血液内，释放出的HBeAg先“麻痹”婴儿的免疫系统，由于HBeAg与HBcAg非常相似，这样，当免疫系统碰到HBcAg时，由于已经被麻痹，于是不再对病毒产生免疫反应，使人体处于免疫耐受状态，无法有效地消灭或清除病毒。乙肝病毒通过释放HBeAg达到逃避人体免疫攻击的目的。这就是为什么，乙肝病毒制造出HBeAg这么一个蛋白，只释放到血液内，而对病毒的复制没有作用。

　　当然，上面只是一种猜测，HBeAg的真正功能，还有待进一步研究和发现。在还没有完全明了它的功能之前，我们知道它是一个绝好的监测病毒的指标就可以了。知道如果HBeAg阳性，就表示病毒复制活跃，血中HBV DNA水平高，传染性强就可以了。”

作者: StephenW 时间: 2011-8-23 23:49

本帖最后由 StephenW 于 2011-8-23 23:51 编辑

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很好，谢谢你。
同一本书，解释了我们如何从免疫耐受进行到免疫清除:

As the years go by, this immune-tolerant phase gives way to increased hepatitic
activity, presumably reflecting immune activation, perhaps as a result of viral antigenic variation caused by transcriptional errors as already mentioned. The role of CD4-positive lymphocytes in this process is supported by the observation of an increased response to the nucleocapsid proteins as HBeAg/anti-HBe seroconversion
approaches. These cells presumably provide help to CTLs and B lymphocytes. Either because of CTL lysis of infected cells, or of cytokine production by CD4-positive lymphocytes, which inhibit virion production, cells supporting productive HBV infection are cleared during the seroconversion hepatitis. About 5% of HBeAg-positive chronic infections may spontaneously seroconvert to anti-HBe per year. In the majority of these patients, HBs antigenaemia persists predominantly because of
the presence of small numbers of cells containing integrated HBV sequences. However, by PCR, it is possible to detect small amounts of HBV DNA in the serum of
these HBsAg-positive, anti-HBe-positive subjects with normal liver function tests, indicating that viral replication is still occurring at low level.

随着岁月的流逝，这种免疫耐受期增加肝炎活动，反映免疫激活，也许作为一个转录错误造成的，前面已经提到的病毒抗原变异的结果。在这个过程中的CD4阳性淋巴细胞的作用是支持增加e抗原/抗- HBe血清转换的核衣壳蛋白反应的观察
方法。这些细胞可能提供帮助的CTL和B淋巴细胞。要么是因为对感染细胞的CTL裂解，或细胞因子的CD4阳性淋巴细胞，从而抑制病毒粒子的生产，生产，配套生产乙肝病毒感染的细胞被清除在血清转换肝炎。抗- HBe，每年大约有5％的HBeAg阳性慢性感染可能自发seroconvert。在这些患者中的大多数，HBs antigenaemia 仍然存在主要是因为包含整合型HBV序列的细胞数量小的存在。然而，经PCR，可以检测到血清HBV - DNA少量这些HBsAg阳性，抗- HBe阳性，肝功能正常的测试，表明病毒复制，科目仍是发生在低水平。

这是，由于多年突变的积累，有一天我们的免疫系统有一个新抗原的目标。免疫系统清除一些受感染的细胞，因此降低eAg生产，因此，减少免疫系统抑制，因此免疫系统更杀死感染细胞, 因此降低eAg生产,因此......最终的平衡 - 少数受感染的细胞在免疫系统的控制下，[像你以前说的] ???

作者: 把握当下 时间: 2011-8-27 12:09

StephenW 发表于 2011-8-23 23:49
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很好，谢谢你。

这是，由于多年突变的积累，有一天我们的免疫系统有一个新抗原的目标。
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恩，我觉得是这样的，根据书里的意思：
免疫耐受开始打破的原因可能是病毒抗原复制时发生了一些错误，这些错误引起了免疫系统的警觉，从而激发了免疫系统对hbv的识别和攻击，慢慢的免疫耐受被打破了

免疫系统清除一些受感染的细胞，因此降低eAg生产，因此，减少免疫系统抑制，因此免疫系统更杀死感染细胞, 因此降低eAg生产,因此......最终的平衡 - 少数受感染的细胞在免疫系统的控制下，[像你以前说的] ???
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恩，我是这个意思，只是免疫激发的后果即可能使病人进入第3期，也可能是第4期（免疫逃避escape，即病毒变异了，东山再起）

In the majority of these patients, HBs antigenaemia persists predominantly because of
the presence of small numbers of cells containing integrated HBV sequences. However, by PCR, it is possible to detect small amounts of HBV DNA in the serum of
these HBsAg-positive, anti-HBe-positive subjects with normal liver function tests, indicating that viral replication is still occurring at low level.
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这里解释了为什么e转换之后，血清表抗仍然很高：因为少许肝细胞已经整合了hbv（基因）序列，仍然在制造表面抗原。如果通过精确pcr定量可能会发现表抗阳性、e抗体阳性、肝功正常的人血清中仍有少量hbv dna，这说明病毒仍在低水平复制（将来可能东山再起）

作者: StephenW 时间: 2011-8-27 16:30

本帖最后由 StephenW 于 2011-8-27 16:30 编辑

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我想补充：
HBsAg颗粒（这些都不会传染），比病毒颗粒（Dane颗粒）的生产多很多倍。这些
HBsAg颗粒流在血液中抑制了我们的免疫系统。

作者: 把握当下 时间: 2011-8-27 19:56

StephenW 发表于 2011-8-27 16:30
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我想补充：

"HBsAg颗粒流在血液中抑制了我们的免疫系统。"
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关于这个论坛有个帖子我觉得很形象：http://www.hbvhbv.com/forum/thread-954135-1-1.html
“27。说说肝炎的原理，当完全的免疫耐受变为不那么完全的免疫耐受时。。。
有一点值得一提，就是乙肝表面抗原还会刺激T细胞大量增殖，而T细胞大量增殖会抑制B细胞的成熟，不成熟B细胞就产生不了表面抗体蛋白。。。。”

作者: StephenW 时间: 2011-8-27 21:15

本帖最后由 StephenW 于 2011-8-27 21:16 编辑

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As zhongdong426 did not provide any references, I cannot verify his claim that increased proliferation of T cells suppresses maturation of B cells:"就是乙肝表面抗原还会刺激T细胞大量增殖，而T细胞大量增殖会抑制B细胞的成熟，不成熟B细胞就产生不了表面抗体蛋白。这点原理很复杂，如果你看不懂，或者我说的不够通俗，可以不必看。看到这里，你可能会怨恨T细胞，T细胞直接杀伤受感染的肝细胞使你的转氨酶升高还不算，增殖的T细胞还抑制B细胞的成熟，导致表面抗体蛋白生产的减少，你很怨恨它对不对？但是免疫系统真的是很复杂的，T细胞对B细胞的制衡有很大意义的，比如，人如果受了辐射导致T细胞受损的话，B细胞就会大量增殖释放大量抗体，就会导致一系列的免疫性疾病的发生，比如，红斑狼疮，自身免疫性的肝炎，风湿性关节炎等等，由此可见，身体中各类免疫反应，不论是细胞免疫还是体液免液，共同构成了一个极为精细、复杂而完善的防卫体系。不能说谁对谁错。"

But he is right that our immune system us very complex. Lifevendor translated a very recent paper about therapeutic vaccine  that talked about T-cell exhaustion
http://www.hbvhbv.com/forum/thread-1042667-1-1.html.

The following abstract also mentioned possible mechanism that HBsAg used to modulate our immune response. All too complicated to me.

http://mt.china-papers.com/2/?p=64955

HBsAg Interferes with the TLR Signaling Pathway in Macrophage-like Cells                            Posted on May 25, 2010 by China Papers 0

Abstract: Hepatitis B virus(HBV),an enveloped virus with a partial circular double-stranded DNA genome,can cause viral necroinflammation with variable severity,resulting in transient acute hepatitis,prolonged chronic hepatitis,or even fatal fulminant hepatitis.It is widely believed that both viral clearance and the development of the liver diseases after infections are determined by host-virus interactions mediated by the immune response.Many studies have shown that the defects in effector functions of the cellular immune response to HBV were responsible for the establishment of HBV infection.However,the precise mechanism of such impaired cellular responses in HBV infection is still to be determined.It is proposed that impaired function of antigen presentation may be involved,since antigen presentation is the prerequisite for priming T cellular immune responses.Toll-like receptor family,the member of pattern recognition receptors,have been identified as crucial mediators of inate immune system by recognizing conservative molecules in pathogens.Studies have shown that activation of antigen presenting cells via TLR signaling is prerequisite for subsequent induction of vigorous T cell responses. Recently,it has been reported that some viruses can interact with TLRs or their downstream molecules to interfere with the signaling cascade.These results suggest that the modulation of TLR-mediated signals is one of the mechanisms for virus to regulate the immune response,which may contribute to viral escape of immune surveillance and the establishment of persistent viral infection.However,it remains unclear whether this kind of immune modulation also exists in HBV infection.In this study,THP-1 cells,a human monocytic cell line,as well as macrophage-like cells differentiated from THP-1 treated with PMA were choosen as cell model for antigen presenting cells.HBsAg was selected to study the effect of HBV on TLR signaling pathway as HBV envelope protein is the most aboundant protein during HBV infection.RT-PCR and Real-time PCR analysis were used to detect TLR mRNA expression.Results showed that macrophage-like cells have a higher TLRs expression profile than THP-1,among which,TLR1,TLR2,TLR4 and TLR6 mRNAs were highly expressed.To investigate the modulatory effects of HBsAg on TLR signaling pathway,pam3csk4 and LPS,which are the TLR1/2 and TLR4 ligands respectively, were used to activate TLR signaling pathway in macrophage-like cells.Results showed that HBsAg inhibited LPS and pam3csk4 induced expression of IL-10 and IL-12 in a dose-dependent manner,which suggests that HBsAg can interfere with TLR signaling pathway activation.In order to further understand the underlying mechanism,the regulatory effects of HBsAg on NF-κB and MARPK pathway,which are downstream of TLR signaling,were detected.Immunofluorescence stainning analysis was used to detect nuclear location of NF-κB p65 protein.Results showed that the number of cells positive for nuclear NF-κB p65 was significantly lower in HBsAg treated cells than in the control cells after pam3csk4 and LPS stimulation. Western blotting analysis showed that LPS and pam3csk4-induced IκB-a degration was also inhibited.All the above results suggest that HBsAg can inhibit LPS and pam3csk4 induced activation of the NF-κB signal pathway.However,no significant change in phosphorylated IκB-a was observed.Further study of the phosphorylated ERK in these cells showed that the induced phosphorylation of ERK by LPS and pam3csk4 were inhibited by HBsAg,indicating the inhibiting effect of HBsAg on the ERK pathway.To further understand the molecular mechanism of interfering with TLR signaling pathway by HBsAg,the TLR expression profiles of HBsAg treated macrophage-like cells were also detected by Real-time PCR.Result showed that there was no significant change of expression of TLRs after treatment with HBsAg, suggesting the inhibition effect is independent of down-regulation of TLRs level. Furthermore,result showed that HBsAg even upregulated TLR4 expression.In addition to interfereing with TLRs recognization,previous studies have demonstrated that some negative regulators were also involved in TLR signaling pathway,including MyD88s,IRAK3,Tollip,IRF family and SOCS family.We next examined the expression of these negative regulators in HBsAg treated macrophage-like cells. Results showed that HBsAg upregulated SOCS1 expression,suggesting the upregulating SOCS1 expression by HBsAg may be one of the mechanisms by which HBsAg interferes with TLR signaling pathway.In conlusion,our studies showed that the presence of large amounts of HBsAg in serum during HBV infection may not only affect adaptive immune response by T cell exhaustion,but also influence the innate immune response by interfering with TLR signaling pathway to arrest antigen presentation.The above studies may provide new insights into the mechanism of inadequate cell-mediated immune response in chronic HBV patients and help to develop novel antiviral therapies…
Key words: HBsAg;  Toll-like receptor;  macrophage-like cell;  THP-1;  SOCS1

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