Objective To observe the effect of hypoxia inducible factor-1α(HIF-1)to the expression of cell surface adhesion molecules CD18 and the adhesion ability of leukoeytes and vascular endothelial cells under early stage of diabetic retinopathy condition. Methods The human promyeloeytic leukemia cell line HL60 and the rhesus choroid-retina vascular endothelial cell line RF/6A were cultured in RPMI 1640 medium-10% human serum, which was collected from the subjects of early stage of diabetic retinopathy and age-matched healthy control. The cells were cultured in 4 groups as control group (group A), diabetic group (group B), HIF-1 anti-sense oligonucleotides (ASODN) group (group C) and HIF-1 sense oligonueleotides (SODN) group (group D). The percentages of CD18 positive cell in the HL60 cell were measured by flow cytometry and mRNA in the HL60 cell by real-time reverse transcription-polymerase chain reaction(RT-PCR). Results The percentage of CD18 positive cell in the group A, B, C and D was 17.06±6.01, 42. 23±2.60, 25.33±3.05 and 32.40±10.57, respectively, the differences among them were significant (F=36.47,P<0. 001). Compared to the group A, the expression of CD18 mRNA in the group B, C and D was increased about 21. 05±2. 07,2. 23±0.96 and 25.07±2.27 times, respectively, the differences among them were significant (F=180.34, P<0. 001). The adherent rates of HL60 to RF/6A in group A, B, C and D was 0. 06±0. 00, 0. 09±0. 10, 0. 05 ±0. 00 and 0.07 ± 0. 01, respectively, the differences among them were significant(F=13.06,P=0. 002). Conclusion In vitro, HIF-1 could regulate the expression of CD18 by HL60, and the adhesion of HL60 to RF/6A when the cells were exposed to diabetic serum. The effects of human serum weaken with the inhibition of HIF-1 expression. HIF-1 play regulatory role in the expression of CD18 and adhesion of leukoeytes and vascular endothelial cells under early stage of diabetic retinopathy condition. Key words: Diabetic retinopathy/Phisiopathology; Hypoxia-inducible factor 1, alpha subunit; Cell adhesion molecules/physiology; Clinical laboratory techniques/methods