Final answer:
Poxviruses express early genes to interfere with host immune defenses such as interferon-induced gene expression and use strategies like antigenic variation and mimicry. They may also hide their antigens using the host cell's plasma membrane to evade detection.
Step-by-step explanation:
Poxviruses have developed strategies to evade the host immune system, one of which includes the expression of early genes that interfere with host defenses. These early genes can be produced quickly and affect the immune response, giving the poxviruses an advantage.
The virus uses proteins that mimic receptors on the cell, enabling them to enter cells and evade antibodies. Moreover, antigenic variation allows the virus to change its surface proteins, rendering the host's antibodies less effective.
Early induced proteins, such as interferons, play a role in the innate immune response but can be subverted by viruses to facilitate infection.
Interferon-induced gene expression typically causes a reduction in cellular protein synthesis, which helps uninfected cells resist viral infection.
However, poxviruses have adapted mechanisms through which they can counteract these changes. By expressing their own early genes, they can interfere with the normal antiviral effects of interferons, potentially by encoding proteins that inhibit the antiviral state of neighboring cells or sequester proteins involved in immune signaling.
Additionally, some poxviruses can use the host cell's plasma membrane to conceal their antigens. By doing so, they can avoid immediate detection by the immune system, thus preventing the immune system from targeting and eliminating the infected cells quickly.