[Tissue specificity of the human brain protein D2]

Area of Science:

• Biochemistry
• Immunology
• Molecular Biology

Context:

• Protein D2 is a protein found in adult human brain.
• Understanding the distribution of protein D2 in various human tissues is crucial for comprehending its physiological roles.

Purpose:

• To isolate and purify protein D2 from adult human brain.
• To generate specific antibodies against purified protein D2.
• To determine the tissue distribution of protein D2 and related antigens in human fetal and adult tissues.

Summary:

• Protein D2 was successfully isolated and purified from adult human brain using Triton X-100 extraction and multiple chromatography techniques (phenyl-sepharose, concanavalin A-sepharose, lysine-sepharose, hydroxylapatite).
• Specific rabbit antisera were raised against the purified protein D2.
• Immunoelectrophoresis techniques revealed the presence of immunoreactive protein D2 in fetal heart, fetal kidney, and adult heart (8-15% of adult brain content).
• Rocket-on-line immunoelectrophoresis further identified smaller amounts of D2-like antigens in adult kidney (12%), adult liver (1.5%), and adult lung and spleen (<1%).

Impact:

• The differential tissue distribution suggests the existence of distinct D2-like protein variants or clones across various human tissues.
• This finding opens avenues for further research into the specific functions and potential roles of these tissue-specific protein D2 variants in health and disease.