The page below is a sample from the LabCE course The Disappearing Antibody: A Case Study. Access the complete course and earn ASCLS P.A.C.E.-approved continuing education credits by subscribing online.

Learn more about The Disappearing Antibody: A Case Study (online CE course) »
How to Subscribe
MLS & MLT Comprehensive CE Package
Includes 97 CE courses, most popular
$95 Add to cart
Pick Your Courses
Up to 8 CE hours
$50 Add to cart
Individual course$20 Add to cart

Cause of Delayed HTR

Delayed HTR result from a secondary (anamnestic) immune response causing a weak, undetectable antibody to become stronger.

Upon re-stimulation by donor red blood cells positive for the antigen corresponding to the patient's antibody:

  • Patient's memory B cells differentiate into antibody-producing plasma cells.
  • As new IgG antibody is produced, it sensitizes antigen-positive transfused donor red blood cells.
  • The IgG-sensitized donor red blood cells are then removed by extravascular hemolysis (EVH) mainly in the spleen.