Prevalence of zinc- 2-glycoprotein binding peptide among Omani blood donors

Abstract

Zinc alpha-2-glycoprotien (ZAG) binding peptide is a multi-functional protein, which is structurally similar to a major histocompatibility complex class I. It has been discovered as a novel adipokine enhancing lipolysis and influencing other physiological processes such as sperm mobility and melanin production. Furthermore, ZAG level has been correlated to a variety of diseases such as atherosclerosis and diabetes type II with a potential use as a tumor biomarker in future. In this study, we aim to investigate the prevalence of ZAG among healthy blood donors attending to the Sultan Qaboos University Hospital blood bank and correlate it with their age and sex. The ZAG levels analysis of the sera from 106 (49 females and 57 males) apparently healthy donors from different regions was carried out using a competitive type of enzyme-linked immunosorbent assay (ELISA) (Abnova GmbH-Germany). Analysis was mainly based on two parameters; age and sex. Out of the 106 subjects, 78% of blood donors have high ZAG levels (>35 ng/ml), 13% have a normal level (20 to 35 ng/ml) while 9% have a level lower than 20 ng/ml. A significant association was found between ZAG level and sex (P = 0.012) with males showing low levels. Although high ZAG level was correlated between age and ZAG levels in the female group, higher levels were also found in donors below and above 22 years old (P = 0.0099). The prevalence of ZAG levels in blood donors was found to be high, especially in those between 20 to 30 years old. This emphasizes the measurement of ZAG level prior to blood transfusion to patient(s) who are clinical under weight. Gender and age significantly influences the plasma level of ZAG.

Removal of Histidine residue from ZN- a-2- glycoprotein by Carboxypeptidase enzyme using Spectrofluorimetry and Maldi-tof-Mass Spectroscopy

“…The solution was centrifuged using Beckman J2 HS centrifuge at 16,000 x g, for 20 minutes at 4°C. As the ZAG form inclusion bodies (Hasson et al 2013), hence it should come in the pellet and therefore the supernatant was discarded. The pellet was washed in Bug buster reagent using the Novagen kit guidelines under the title: Inclusion Body Purification to remove the cellular debris.…”

“…The poly-histidine tag greatly facilitates the purification of recombinant proteins; however the presence of additional residues may induce subtle effects and compromises the biological activity of recombinant protein (Hasson et al 2013). Researchers have employed different strategies for successful removal of histidine-tail residues (Arnau et al 2006).…”