α-Interferon to Hepatitis B

Lecturer: Sun fengkai

Team members : Qixin Jiaming Songhaiyang Yulingqi Zhangwen Zhaoliang

Introduction

Outlook of the Interferon

Recent Development of Interferon

Mechanism of α-IFN in treatment of HBV

Mechanism of HBV Pathogenesis

Epidemiology of Hepatitis B

一、 Epidemiology of Hepatitis B

Epidemiology of Hepatitis B

Hepatitis B is one of the most serious diseases in the world . The infection rate of the chronic hepatitis B virus (HBV) in world is as high as 25 percent, about 350 million HBV carriers, and the figure is still rising rapidly year by year!

China is the high infective prevalent areas of HBV, there are about 120 million cases of chronic HBV infection, including chronic hepatitis B (CHB)with 30 million cases. It is the main reason for liver cirrhosis and liver cancer. 30,000~ 50,000 deaths cases each year.It is of great harm to people's health.

Epidemiology of Hepatitis B

二、Mechanism of HBV Pathogenesis

Mechanism of HBV Pathogenesis

In modern medicine, the pathogenesis of chronic hepatitis B(CHB) is related to the continuous replication of HBV and immune dysfunction in the body.

The reason of CHB repeated attacks is that HBV is a highly various virus, which easily leads to a mutation of HBV and is hard to recover.

After the HBV invading organism, it first infects the liver cell, produces the integrity HBV-DNA and secretes HBcAg, HBsAg and HBeAg.

Mechanism of HBV Pathogenesis

Mechanism of HBV Pathogenesis

HBV does not cause the liver cell damage directly. It causes damage by immune response of human body.

The viral-antigen in the blood or on the liver cell membrane may induce the immune response to attack the infected liver cells and cause the damage of the liver cells.

Mechanism of HBV Pathogenesis

Cell –mediated immune response

Antibody- mediated hypersensitivity

Autoimmune injury

damage bodydamage body

Mechanism of HBV Pathogenesis

三、Mechanism of α-IFN in treatment of HBV

Mechanism of α-Interferon in treatment of HBV

1. IFN-α is the earliest and most widely used drug to anti-virus infection. And it is a kind of CKs that is used to anti-virus and regulate the immunity.

Mechanism of α-Interferon in treatment of HBV

2. Antiviral mechanisms Not act directly on virus, but induce synthesis of the cellular antiviral proteins(AVP).

1 2 3 4

IFN combines with specific receptor on cell surface

signal transduction

induce the activation of AVP gene

transcription of AVP mRNA

synthesis of AVP

Mechanism of α-Interferon in treatment of HBV

HBV

HBV replication Inhibit HBV replication

Signal transduct

IFN-

AVPstimulate

nucleusnucleus

Mechanism of α-Interferon in treatment of HBV

receptor

3、modify immune responses

---- activation of NK cell

---- activation of macrophage

---- increase expression of MHC molecules,regulate IL-1,IL-2,TNF,and enhance the proliferation of CTL

Mechanism of α-Interferon in treatment of HBV

四、 Recent Development of Interferon

Recent Development of Interferon

Smaller Bigger

vs

interferon added with PEG

Stronger

Unstable

Faster

Weaker

stable

Slower

Molecule

Immunogenicity

Stability

Absorb rate

common interferon

With the addition of PEG to the interferon, proper concentration can be kept for a long time, but the affinity to the receptor on the cells will be decreased.

Recent Development of Interferon

Later, people find that 12KD PEG is suitable because its effect to decrease the affinity is the smallest.

Recent Development of Interferon

The peg-interferon is the example. It has about 30% renal filtration rate.

The half-life is forty hours.

Recent Development of Interferon

The usage is one injection one week .

The anti-virus activity is high.

Recent Development of Interferon

Another drug is the pegsys.

Its mechanism is the same as the peginterferon but the PEG part is 40KD.

Recent Development of Interferon

Because of the bigger part of PEG, pegsys have a longer half-life about 80h.

The protection is better, and the drug concentration is more stable.

五、 Outlook of the Interferon

Outlook of the Interferon

Interferon has broad-spectrum antiviral activity. It is a good drug to rejest virus and keep heath. Recently, thousands of children in Fuyang are infected with EV71. By now,there are 3736 cases.1460 cases have recovered and 22 cases died.

It is a pity that no vaccine can defend it and no specific drugs can treat this diease. However, we believe that interferon will play an indispensible role in the treatment of EV71. Of course, new methods are still waiting for us to discover and put in use!

Outlook of the Interferon

What we should do now is to study hard and master immunology, which will be very helpful!

Outlook of the Interferon