LOCALIZATION OF ANTIBODIES BY ELECTRON MICROSCOPY IN DEVELOPING ANTIBODY-PRODUCING CELLS

Area of Science:

• Immunology
• Cell Biology
• Microscopy

Background:

• The secondary immune response involves rapid antibody production by specialized cells.
• Understanding the initial stages of antibody synthesis is crucial for immunology.

Purpose of the Study:

• To investigate the early intracellular localization of antibodies during the secondary immune response.
• To identify the specific cell types involved in initial antibody production.

Main Methods:

• Electron microscopy was used to examine lymph node cells in rabbits post-immunization.
• A labeling technique was employed to detect antiferritin antibodies within cells.
• Cellular structures like the endoplasmic reticulum and Golgi apparatus were analyzed.

Main Results:

• Antibodies were first detected in blast cells approximately 48 hours after booster injection.
• Antibody presence was observed in intermediate cells (plasmablasts, immature plasma cells) as endoplasmic reticulum developed.
• Antigen-antibody precipitates were found in the perinuclear space and endoplasmic reticulum cisternae.
• Antibodies were also detected in the Golgi area and in cells undergoing mitosis.

Conclusions:

• Antibody synthesis initiates in blast cells with rudimentary endoplasmic reticulum.
• The development of the granular endoplasmic reticulum is associated with increasing antibody accumulation.
• These findings provide insights into the cellular sites of antibody synthesis during an active immune response.