PB0123 - Investigation of differences in levels of VEGF-A121 and VEGF-A165 in plasma, serum, and platelets

Sunday, June 23, 2024

13:45 – 14:45 ICT

Room: Exhibition Hall

Presenting Author(s)

Munekazu Yamakuchi, PhD, MD

associate professor
Kagoshima University Graduate School of Medical and Dental Sciences
Kagoshima, Kagoshima, Japan

Co-Author(s)

MO

Masashi Okawa

graduate student
Kagoshima University Graduate School of Medical and Dental Sciences
Kagoshima, Kagoshima, Japan
KT

Kazunori Takenouchi

assistant professor
Kagoshima University Graduate School of Medical and Dental Sciences
Kagoshima, Kagoshima, Japan
SH

Sadayuki Higashi

graduate student
Kagoshima University Graduate School of Medical and Dental Sciences
Kagoshima, Kagoshima, Japan
CF

Chieko Fujisaki

graduate student
Kagoshima University Graduate School of Medical and Dental Sciences
Kagoshima, Kagoshima, Japan
AT

Akito Tabaru

graduate student
Kagoshima University Graduate School of Medical and Dental Sciences
Kagoshima, Kagoshima, Japan
YO

Yoko Oyama

specially appointed assistant professor
Kagoshima University Graduate School of Medical and Dental Sciences
Kagoshima, Kagoshima, Japan
KT

Kiyonori Tanoue

doctor
Kagoshima University Hospital Clinical Laboratory
Kagoshima, Kagoshima, Japan
TH

Teruto Hashiguchi

professor
Kagoshima University Graduate School of Medical and Dental Sciences
Kagoshima, Kagoshima, Japan

Background: Vascular endothelial growth factor-A (VEGF-A) plays a pivotal role in the regulation of physiological vascular function and tumor angiogenesis. We have successfully generated monoclonal antibodies against the major VEGF-A isoforms, human VEGF-A121 (hVEGF-A121) and human VEGF-A165 (hVEGF-A165). Using these antibodies, enzyme-linked immunosorbent assay (ELISA) systems specific for VEGF-A121 or VEGF-A165 were created.

Aims: To clarify the role of VEGF-A isoforms, the levels of VEGF-A121 and VEGF-A165 in bloods and platelets in healthy individuals were investigated.

Methods: Whole blood was collected from healthy volunteers to collect serum, plasma, and platelet rich plasma. The research ethics committees of Kagoshima University Hospital approved this study (Approval number 180198). By using our ELISAs, the amounts of VEGF-A121 and VEGF-A165 were measured in cultured media of HEK293 cells and in human serum, plasma, and platelets.

Results: These ELISAs accurately recognized recombinant hVEGF-A121 and hVEGF-A165 and confirmed that measurement of hVEGF-A121 and hVEGF-A165 did not cross-react in culture supernatants of HEK293 cells transfected with expression plasmids of either hVEGF-A121 or hVEGF-A165. VEGF-A121 and VEGF-A165 were measured in serum, plasma, and platelets of fifty-nine healthy volunteers. VEGF-A121 or VEGF-A165 was higher in serum than in plasma. VEGF-A121 was higher than VEGF-A165 in both plasma and serum. In platelets, on the other hand, VEGF-A165 was higher than VEGF-A121, which differed from the serum and plasma data. Comparing VEGF-A121 and VEGF-A165 released outside of platelets when platelets were stimulated with thrombin, more VEGF-A121 was released from platelets than VEGF-A165. One plausible reason for the distinct ratios of VEGF isoforms in serum, plasma, and platelets is that the secretory mechanisms of VEGF-A121 and VEGF-A165 are different.

Conclusion(s): Our study showed that the ratio of VEGF-A121 to VEGF-A165 differed in serum, plasma, and platelets; combined measurement of the two isoforms, VEGF-A121 and VEGF-A165, is a potential biomarker for various diseases.