HSPA5 and axial length measurement: In contrast, the massive protein synthesis in rapidly growing AL cells was found to recruit high levels of ribosomes and HSP chaperones, in particular cytosolic Hsp90AB1 and HSC70 (HSPA8) and endoplasmic reticulum HSP90B1 and BIP (HSPA5), which are general hallmarks of heat-, chemical- and/or cellular-stresses [28, 29].