Micro

Question 1

Influenza vaccine

Answer 1

• TWO types:
  
  • 1. inactivated/killed-injection
       * induce neutralizing Ab vs. hemagglutinin Ag in SELECTED viral strains
       * subsequent exposure thru natural infection: Ab INHIBIT binding of hemagglutinin to sialylated receptors on the host cell-membrane
       
       • prevent live virus from entering cells via ENDOcytosis
  • 2. live/attenuated-nasal
       * strongly stimulate MHC class 1 Ag-processing PW
       * can generate cytotoxic CD8+ T lymphocytes that KILL infected cells

Question 2

What interferons do virally-infected cells release

Answer 2

• Inteferon alpha and beta
  
  • induce synthesis of ANTI-viral proteins in NEIGHBORING cells
  • these proteins LIMIT ability of many viruses to spread through the tissues by SUPPRESSING viral replication and assembly

Question 3

Osel-TAMIVIR vs. Neuraminidase

Answer 3

• NA: cleaves terminal sialic acid residues on glycoconjugate receptors=release of attached influenza virions from infected cells
• Osel-TAMIVIR=sialic acid analogue
  
  • COMPETITIVELY inhibits influenza NA
    
    • prevents release of viral progeny