Herpesviridae and You

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Herpesviridae and You

• Adrienne Manuel
• I400

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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 pathogensthe
  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.

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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.

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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.

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• 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.

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• 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.

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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.

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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

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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.

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HERPES SIMPLEX 1 and 2
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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 viruss infectivity and
  to the induction of host immune responses.

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UL52

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

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UL9

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

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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

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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.

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• 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.