Herpesviridae and You Adrienne Manuel I400

THE Immune system: a brief overview For Humans and animals to have maximum health, their bodies needs defense systems that are able to recognize and repel diseases and pathogens—the Immune System. The Immune system is made up of cells and tissues. What makes the immune system so remarkable is its ability to recognize between self and non-self.

Overview continued… The immune systems carries several types of fighter cells (B lymphocytes, T Cells, Phagocytes, Cytokines, etc) in the body to help recognize certain disease and viruses.

Types of Immune Cells B cells work on creating antibodies in bodily fluids. These Antibodies attack antibodies in the bloodstream but cannot penetrate into cells. B cells create these antibodies that are then “customized” the antigen Immunoglobulins help coat microbes, fight viruses, killing bacteria, etc. T cells are also another helpful resource to the immune system.

T Cells aid the immune system in two different ways: some direct and regulate immune responses; others directly attack infected cells. Phagocytes are large white cells that ingest foreign microbes and particles. Cytokines are chemical messengers shared amongst to access an antigen and what immune response to take.

Lastly there is the complement system that consists of roughly 25 proteins that aid antibodies to destroy antigens. The Complement proteins circulate in the blood non-active.

Creating an Immune Response Once the pathogens find their way into the body (through a cut through the skin or tiny abrasions), they must go through the wall linings that are made up of tightly packed epithelial cells. These cells are hard to penetrate because they are covered in a thick mucus. The mucus contains Immunoglobulin A, which guards entrances, and usually the first antibody a microbe encounters. When an antigen is found, antibodies are triggered by the B cells. The B cell surrounds the antigen and digests it.

The Herpes Virus 100 different strains found in a myriad number of species Belongs to the Herpesviridae Family There are three Subfamilies: Alphaherpesvirinae, Betaherpesvirinae, Gammaherpesvirinae

HERPES! These viruses all have certain characteristics in common, like the ability to establish latency during primary infection Herpes viruses are able to hide within the cells in the body as protection from the antibodies produced by the immune system The viruses are triggered due to factors of stress, illness, or poor nutrition.

HERPES SIMPLEX 1 and 2

Similar proteins: Glycoprotein B This protein is exposed on the viral envelope and on the surface of infected cells. 91% match found in the Protein B in HSV-2 are responsible for the virus’s infectivity and to the induction of host immune responses.

UL52 Interacts with 2 other proteins. UL5, UL8. UL52 combined with UL8, Herpes simplex virus type 1 expresses a heterotrimeric helicase–primase, UL5 and UL52 subunits of the helicase–primase seem to play an important role in modulating the helicase–primase activity and integrating this activity into the whole function of the replisome

UL9 UL9 is responsible for the virus’ DNA It is thought that UL9 binds the origin of replication

How Herpes work Viral glycoproteins allow the virus to attach and enter the cell. The envelope and cell membrane fuse the viral capsid is released into the cytoplasm. Viral DNA enters the nucleus and the capside is discarded. Host enzymes catalyze the early transcription, and viral mRNA directs the production of viral enzymes. These enzymes facilitate the replication of viral DNA. Late transcription produces the mRNA encoding the production of glycoproteins and capsid elements. The capsid components return to the nucleus and the DNA is packaged. he glycoproteins fix themselves to the nuclear membrane and the DNA filled capsid acquires this coat as it buds out of the nucleus. The virus is released from the cell by unknown mechanisms

Herpes Simplex Proteins and their similarities The DNA sequences of HSV-1 and HSV-2 are 50% identical in their nucleotide sequences and their proteins are even more closely related. HSV-1 is responsible for more than 90% of oro-labial herpes (blisters found on the lip) whereas HSV-2 is responsible for over 90% of genital herpes infections.

The comparison above taken from BugSpray below shows genome alignment based on similar genes and illustrates the similar gene arrangement between the HSV-1 and HSV-2. Lines run from the genes on the top genome (HSV-2) to the gene with the best BLAST hit in the bottom genome in HSV-1. The Green lines indicate pairs of genes that similar to the same strand. The red lines indicate gene pairs that code on the opposite strand. There are no rearrangements or reordering of genes between these two viruses.