Scientists found that a tiny synthetic piece of the thymosin‑alpha‑1 protein (called LKEKK) sticks tightly to human T‑cells, and this binding isn’t broken down by enzymes, meaning the receptor isn’t a typical protein. The same spot can also be blocked by the full thymosin‑alpha‑1, interferon‑alpha‑2, and cholera toxin B, showing they share a common binding site. However, the study only maps this interaction and doesn’t show any health effects or dosing advice.

The synthetic peptide LKEKK corresponding to sequence 16-20 of human thymosin-α1 and 131-135 of human interferon-α2 was labeled with tritium to specific activity 28 Ci/mol. The [3H]LKEKK bound with high affinity (Kd = 3.7 ± 0.3 nM) to donor blood T-lymphocytes. Treatment of cells with trypsin or proteinase K did not abolish [3H]LKEKK binding, suggesting the non-protein nature of the peptide receptor. The binding was inhibited by thymosin-α1, interferon-α2, and cholera toxin B subunit (Ki = 2.0 ± 0.3, 2.2 ± 0.2, and 3.6 ± 0.3 nM, respectively). Using [3H]LKEKK, we demonstrated the existence of a non-protein receptor common for thymosin-α1, interferon-α2, and cholera toxin B-subunit on donor blood T-lymphocytes.