PD-1 Dimer Formation: Contrary to previous understanding, PD-1 forms dimers, impacting its function in suppressing T cell activity.

Cancer Treatment Enhancement: Insights into PD-1 dimerization offer potential for improving cancer immunotherapies by manipulating its function.

Autoimmune Disease Therapy Design: Understanding PD-1's role opens avenues for designing therapies for autoimmune disorders by modulating its dimerization.

Transmembrane Segment Significance: The study highlights the importance of PD-1's transmembrane segment in regulating immune responses.

Amino Acid Structure Influence: Changes in the amino acid structure of PD-1's transmembrane segment can enhance or diminish its inhibitory function in immune responses.