Insulin-like growth factors (IGF-I, free IGF-I and IGF-II) and insulin-like growth factor binding proteins (IGFBP-2, IGFBP-3, IGFBP-6, and ALS) in blood circulation.
Author(s): Yu H, Mistry J, Nicar MJ, Khosravi MJ, Diamandis A, van Doorn J, Juul A
Publication: J Clin Lab Anal, 1999, Vol. 13, Page 166-72
PubMed ID: 10414596 PubMed Review Paper? No
Suggested by: ISBER
Purpose of Paper
The purpose of this paper was to determine the effects of patient age and gender, anticoagulant, use of serum rather than plasma and freeze-thaw cycling on insulin-like growth factors (IGF) and IGF binding proteins (IGFBP) in blood.
Conclusion of Paper
IGF-I, IGF-II, IGFBP-3, IGFBP-6 and the acid-labile subunit of IGFBP (ALS) increased while IGFBP-2 decreased with age between birth and puberty in serum and/or plasma. After puberty, IGF-I, IGFBP-3, and ALS declined slowly with age while IGF-II, IGFBP-2, and IGFBP-6 remained relatively constant. Levels of IGF-I, IGFBP-3 and ALS were higher while IGFBP-2 and IGFBP-6 were generally lower in females than males in serum and/or plasma. IGF-I and II were 10% higher in serum than plasma, but the type of anticoagulant used had no effect on IGF-I or II levels in plasma. Serum had significantly higher IGFBP-3, IGFBP-6 and ALS levels and lower IGFBP-2 levels than EDTA-plasma. Serum had significantly higher IGFBP-2, IGFBP-6 and ALS levels than heparinated plasma, but there were no differences in IGFBP-3 levels between serum and heparinated plasma. IGFBP-3 and ALS levels were significantly higher and IGFBP-2 levels were significantly lower in heparinated plasma than in EDTA-plasma. IGF-I, IGF-II and IGFBP-3 levels, in plasma, were not significantly different after 5 freeze-thaw cycles.
Studies
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Study Purpose
The purpose of this study was to determine the effects of patient age and gender, anticoagulant, use of serum rather than plasma and freeze-thaw cycling on IGF and IGFBP in blood. Specimens used to measure IGF-I and ALS were kept frozen until use, but specimens used to measure IGF-II, IGFBP-2, IGFBP-3, and IGFBP-6 had been previously thawed.
Summary of Findings:
IGF-I, IGF-II, IGFBP-3, IGFBP-6 and ALS levels increased while IGFBP-2 decreased with age between birth and puberty in serum and/or plasma. After puberty, IGF-I, IGFBP-3, and ALS declined slowly with age while IGF-II, IGFBP-2, and IGFBP-6 remained relatively constant. Levels of IGF-I and IGFBP-3 were 8% higher in females than males. Levels of ALS were generally higher, while IGFBP-2 and IGFBP-6 were generally lower in females than males in serum. There was no effect of gender on IGF-II levels. IGF-I and II were 10% higher in serum than in plasma (p<0.001), but the type of anticoagulant used had no effect on IGF-I or II levels in plasma. Serum had significantly higher IGFBP-3, IGFBP-6 and ALS levels and lower IGFBP-2 levels than EDTA-plasma. Serum had significantly higher IGFBP-2, IGFBP-6 and ALS levels than heparinated plasma, but there were no differences in IGFBP-3 levels between serum and heparinated plasma. IGFBP-3 and ALS levels were significantly higher (p<0.001 and p=0.009, respectively) while IGFBP-2 levels were significantly lower (p<0.001) in heparinated plasma than in EDTA-plasma. IGF-I, IGF-II and IGFBP-3 levels, in plasma, were not significantly different after 5 freeze-thaw cycles.
Biospecimens
Preservative Types
- Frozen
Diagnoses:
- Normal
- Other diagnoses
Platform:
Analyte Technology Platform Protein Immunoassay Protein Immunoradiometric assay Protein ELISA Protein Radioimmunoassay Pre-analytical Factors:
Classification Pre-analytical Factor Value(s) Biospecimen Aliquots and Components Blood and blood products Plasma
Serum
Storage Freeze/thaw cycling 1 cycle
2 cycles
3 cycles
4 cycles
5 cycles
Preaquisition Patient age 5-65 years
Preaquisition Patient gender Female
Male
Preaquisition Diagnosis/ patient condition Minor throat infection
Minor ear infection
Biospecimen Acquisition Anticoagulant Citrate
EDTA
Heparin
None