International standards for growth hormone.

Area of Science:

• Endocrinology
• Biotechnology
• Laboratory Medicine

Background:

• The World Health Organization established the first International Standard (IS) for bovine growth hormone (GH) in 1955.
• Currently, two GH ISs are in use: one for human GH (1982) and one for somatropin (1994).
• The existence of multiple GH standards hinders the reproducibility of GH measurements across different laboratories.

Purpose of the Study:

• To address the lack of reproducibility in GH estimates between laboratories.
• To propose a unified international standard for GH immunoassays.

Main Methods:

• Review of historical developments in GH standardization.
• Analysis of the current landscape of GH International Standards.
• Proposal for the adoption of a single, validated international standard.

Main Results:

• The current availability of two distinct GH International Standards (IS) negatively impacts inter-laboratory reproducibility.
• The IS for somatropin possesses an internationally agreed specific activity of 3 IU/mg.
• This standard offers a significant advantage for consistent GH quantification.

Conclusions:

• The adoption of the IS for somatropin as the primary reference standard for all GH immunoassays is proposed.
• This unified approach is expected to eliminate variations in GH estimates.
• Implementing this standard will enhance global consistency and reliability in GH bioassays.