「Correlates of Protection」の版間の差分

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*Theoretically
 
*Theoretically
 
**To measure immune responses '''at the time of exposure to the infection''' and compare them between those who get infection and not
 
**To measure immune responses '''at the time of exposure to the infection''' and compare them between those who get infection and not
***might be feasible by detecting immune responses of bloods donated just before an outbreak
+
***''might be feasible by detecting immune responses of bloods donated just before an outbreak''
 
*Practically
 
*Practically
 
**To measure immune responses '''after the vaccination''' and compare them between those who get infection and not
 
**To measure immune responses '''after the vaccination''' and compare them between those who get infection and not

2022年10月22日 (土) 14:27時点における版

Correlates of Protection

Definitions of terms
Correlates of Protection (CoP) An immune response statistically correlated with protection
Mechanistic CoP (mCoP) An immune response responsible for protection
Non-mechanistic CoP (nCoP) An immune response surrogating mCoP and easily measured

Identifying method of CoP (mCoP)

  • Theoretically
    • To measure immune responses at the time of exposure to the infection and compare them between those who get infection and not
      • might be feasible by detecting immune responses of bloods donated just before an outbreak
  • Practically
    • To measure immune responses after the vaccination and compare them between those who get infection and not
      • usually done in vaccine clinical trial phase 3
    • To measure immune responses at the time of challenging exposure of vaccinated volunteers
      • would be ethically approved only for milder and/or treatable infections such as seasonal influenza, cholera, dengue or cytomegalovirus
    • To extrapolate vaccinated animal challenge model
    • To extrapolate protective level of dosing of passive immunization (antibody treatment)

Be careful

  • "Immune reseponses" contain various kinds of immunological functions
    • Serum antibodies with multiple isotypes and multiple functions
    • Mucosal antibodies with multiple isotypes and multiple functions
    • Helper T cells
    • Killer T cells
    • Regulatory T cells
    • etc.
  • Protection against infection is generally different from protection against disease
    • You should focus on which type of protection you expect
Protection against infection Protection against disease
Polio Infection is prevented by mucosal antibodies at nasopharynx and intestine (IgA + diffused IgG) Disease (paralysis) is prevented by serum antibodies before entering CNS via blood
Pneumococcus Infection (bacteremia) is prevented by 0.20-0.35 µg/mL (ELISA) of serum antibodies Disease (pneumonia, otitis media, nasopharynx carriage) is prevented by >10 times higher serum antibodies