Thymosin beta 4 sequesters the majority of G-actin in resting human polymorphonuclear leukocytes

Cassimeris L, Safer D, Nachmias VT, Zigmond SH · The Journal of Cell Biology

Thymosin β4 was present at roughly 149 µM in the cytoplasm (169 fg per cell) and held most of the free G-actin pool; the complex fell when cells were stimulated to polymerise actin, establishing Tβ4 as the cell's principal actin-monomer buffer.

Population

Human polymorphonuclear leukocytes

Intervention

None — quantification of endogenous thymosin β4 and its actin complex

Comparator

Resting vs chemoattractant-stimulated cells

Limitations

Descriptive cell biology in one leukocyte type; says what the protein does inside cells, not what injecting it does to tissue.