A mass of genetic material that can replicate autonomously

located in the center of the virion

a type of nucleic acid DNA or RNA

small amounts of non-structural proteins

protein shell surrounding nucleic acids

Structure (different according to the arrangement of capsomeres)

The main function

protein

polysaccharide

Lipids

1. Protect the virus: Maintain the integrity of the virion structure

2. Participate in infection: related to virus invasion

3. Antigenic

have

none

Electrostatic adsorption (random collision)

non-specific receptor adsorption

form

At this stage, the virus's infectivity disappears and enters the latent period.

Most are uncoated under the action of host cell lysosomal enzymes

nucleic acid replication

protein synthesis

DNA viruses assemble in the cell nucleus

Most RNA viruses assemble in the cytoplasm

Unencapsulated

Encapsulated

Unencapsulated

Encapsulated

unable to reproduce normally, Complete infectious virus particles cannot be replicated,

After the virus enters the host cell, if the cell cannot provide the enzymes, energy and necessary components required for virus proliferation, it will not be able to replicate complete virus particles.

A helper-deficient virus that completes normal multiplication.

The virus induces cells to produce glycoproteins that inhibit viral replication, namely interferon

The virus destroys the receptor site on the surface of the host cell, Prevent the adsorption or penetration of another virus

Infection with a virus alters host cell metabolism, Prevent translation of second viral mRNA, etc.

among different individuals in the crowd

Passed from parent to offspring of the host

The virus invades the body but does not cause clinical symptoms

The virus invades the body and proliferates in susceptible cells, producing tissue damage and toxic products, leading to clinical symptoms and signs.

Classification

After the virus replicates in the host cell, it can A large number of progeny viruses are released at once, and the cells are lysed and die.

Cytopathies are mild and do not dissolve and die within a short period of time, which is common in enveloped viruses.

In some virus-infected cells, use Ordinary light microscope can see round or oval plaques that are different from normal cell structure and coloration.

Causes host apoptosis and promotes virus release in cells, But it also limits the number of virions produced by the cell.

closely related to tumor formation

Glycoproteins act on body cells and can show anti-viral and anti- Biological activities in many aspects such as tumors and immune regulation

It has broad-spectrum antiviral effects. It can only inhibit viral replication (protein), but cannot kill viruses. It induces cells to synthesize antiviral drugs. Protein comes into play

CTL (cytotoxic T lymphocytes)

Activated Thl

virus neutralizing antibodies

IgG, Igll and IgA have different functions