Human Varicella Zoster Immune Globulin

Specification

• Cat#: THP-0177
• Product Name: Human Varicella Zoster Immune Globulin
• Description: The product is a solvent/detergent-treated sterile liquid preparation of purified human immune globulin G (IgG) containing antibodies to varicella zoster virus (anti-VZV). It is prepared from pools of healthy human donors' plasma via anion-exchange column chromatography.
• Sequences: Not Available
• Species: Human
• Molecular Weight: Not Available
• Source: Human Plasma
• Cas No: Not Available
• Formula: Not Available
• Endotoxin Level: <0.001 EU per 1 μg of the peptide by the LAL method
• Biological Activity: 100IU/ml

Pharmaceutical Information

• Pharmaceutical Application: Human Varicella-Zoster Immune Globulin
• Applications: Indicated for preventing and reducing the severity of chicken pox (varicella zoster virus) infections in high risk individuals within 4 days of exposure to varicella zoster virus.
• Examples of Clinical Use: Chicken pox (varicella zoster virus) infections
• Pharmacodynamics: The product provides passive immunization for non-immune individuals exposed to VZV, reducing the severity of varicella infections.
• Mechanism of action: Immunoglobulins are derived from human plasma and synthesized from plasma cells that recognize a broad spectrum of specific antigenic determinants.Derived from a pool of healthy human plasma, Human Varicella-Zoster Immune Globulin is a solvent/detergent-treated sterile lyophilized preparation of purified human immune globulin G (IgG) containing antibodies to varicella zoster virus. The anti-VZV antibodies in VariZIG™ are thought to bind to proteins on the varicella virus; thereby, preventing or reducing the severity and progression of varicella infections.
• Affected organisms: Not Available

Related Reading

1. Discovery of Human Varicella Zoster Immune Globulin

Human Varicella Zoster Immune Globulin (VZIG) is a medical product derived from plasma, used for the prevention and treatment of varicella-zoster virus (VZV) infections. Here is a brief overview of its discovery and development:

1. Identification of Varicella-Zoster Virus (VZV): The varicella-zoster virus was first isolated and identified in the late 1950s and early 1960s by several researchers independently. It was discovered to be the same virus responsible for causing both chickenpox (varicella) and shingles (herpes zoster).
2. Plasma Fractionation Techniques: In the early days of blood product development, researchers developed techniques to fractionate plasma, separating it into various components such as albumin, immunoglobulins, and clotting factors. These techniques paved the way for the production of immune globulins, including the development of VZIG.
3. Development of VZIG: In the 1970s, researchers began investigating the use of immune globulin preparations to provide passive immunity against various infections. Given the success of immune globulin usage in preventing diseases like measles and hepatitis, there was interest in developing a similar product for VZV.
4. Collection of Plasma from Convalescent Donors: Donors who had recently recovered from varicella or herpes zoster were identified and recruited. Plasma samples were collected from these donors, which contained antibodies specific to VZV.
5. Purification and Formulation: The collected plasma samples were subjected to various purification processes to remove unwanted components. The goal was to concentrate and isolate the specific antibodies against VZV. The purified antibodies were then formulated into a product known as Varicella Zoster Immune Globulin (VZIG).
6. Clinical Trials and Approval: Clinical trials were conducted to evaluate the safety and efficacy of VZIG. These trials involved giving VZIG to individuals at high risk of severe VZV infections, such as immunocompromised patients or newborn infants whose mothers developed chickenpox during pregnancy. The results demonstrated the effectiveness of VZIG in preventing or reducing the severity of VZV disease.
7. Marketing and Availability: Following successful clinical trials and regulatory approval, VZIG became commercially available for medical use. It is typically administered to individuals who have been exposed to VZV and are at high risk of severe complications, providing passive immunity and reducing the likelihood of disease development or progression.

Since the discovery and development of VZIG, it has been a crucial tool in preventing and managing VZV infections, particularly in individuals who are vulnerable to severe disease.

2. Function and structure of Human Varicella Zoster Immune Globulin

Human Varicella Zoster Immune Globulin (HVZIG) is a medication used to prevent or attenuate varicella zoster virus (VZV) infection in people who are at high risk of severe complications or have been exposed to the virus. It is prepared from plasma donated by individuals who have high levels of antibodies against VZV.

Function:

HVZIG contains high titers of antibodies that specifically target and neutralize VZV. When administered to individuals, these antibodies provide passive immunity, meaning they offer immediate protection against VZV infection. The antibodies in HVZIG bind to the virus, preventing it from entering cells and causing an infection. This helps reduce the severity or prevent the development of chickenpox or shingles.

Structure:

HVZIG is a sterile, clear to slightly opalescent, and colorless to pale yellow liquid. It is prepared from pooled human plasma collected from donors who have high levels of antibodies against VZV. The plasma is processed to remove potential contaminants such as viruses and plasma proteins. The resulting HVZIG product contains highly purified immunoglobulin G (IgG) antibodies, which are the main type of antibodies responsible for immunity against VZV.

The structure of HVZIG is composed of IgG molecules, which are Y-shaped proteins consisting of two heavy chains and two light chains. The IgG antibodies in HVZIG have specific binding sites that allow them to recognize and bind to viral antigens found on VZV. This binding triggers different immune responses, including neutralization of the virus, activation of immune cells, and clearance of the virus from the body.

3. The medical application of Human Varicella Zoster Immune Globulin

The medical application of Human Varicella Zoster Immune Globulin (HVZIG) is primarily for the prevention or attenuation of varicella zoster virus (VZV) infection in individuals who are at high risk of complications or have been exposed to the virus.

1. Prevention of severe chickenpox: HVZIG can be administered to individuals who are at high risk of severe complications from chickenpox. This includes immunocompromised individuals, pregnant women, infants born to mothers with active chickenpox near the time of delivery, and individuals with certain medical conditions. HVZIG provides passive immunity to these individuals, helping to prevent or lessen the severity of chickenpox if they are exposed to VZV.
2. Post-exposure prophylaxis: HVZIG can also be used for post-exposure prophylaxis in individuals who have not been vaccinated against VZV or do not have immunity. This is especially important for individuals who have been in close contact with someone who has chickenpox or shingles. HVZIG administration within 96 hours of exposure can help prevent or reduce the severity of disease in susceptible individuals.
3. Prevention of severe shingles: HVZIG is also used as a preventive measure for individuals at high risk of developing severe complications from shingles. This includes individuals with compromised immune systems, such as those with HIV/AIDS or undergoing immunosuppressive therapy. HVZIG administration can help attenuate or prevent the development of shingles in these individuals.

It is important to note that HVZIG is not a treatment for active varicella or shingles infection. It is only effective in preventing or attenuating the infection when administered prior to or shortly after exposure to VZV.