Similarities in sequences and cellular expression between rat CD2 and CD4 antigens.

Area of Science:

• Immunology
• Molecular Biology
• Cell Biology

Background:

• The MRC OX-34 antigen is found on rat T lymphocytes.
• Understanding its structure and function is crucial for immunology research.

Purpose of the Study:

• To purify and characterize the MRC OX-34 antigen.
• To determine its relationship to known cell surface molecules, particularly human CD2 and CD4.

Main Methods:

• Purification of the MRC OX-34 antigen from rat T lymphocytes.
• Peptide sequencing and cDNA cloning for protein sequence determination.
• Sequence comparison with human CD2 and CD4 antigens.

Main Results:

• MRC OX-34 was identified as rat CD2.
• Rat CD2 possesses a large cytoplasmic domain and structural similarities to CD4.
• CD2 expression was observed on most T lymphocytes and splenic macrophages, but not all thymic cells or other macrophage populations.

Conclusions:

• Rat CD2 shares structural and cellular expression characteristics with CD4.
• CD2 exhibits a broad expression pattern across T cell development and on macrophages.
• The findings contribute to understanding T cell recognition and immune cell interactions.