Experiments conducted on the human parasite Leishmania major

Experiments conducted on the human parasite Leishmania major has shown that specific parasitic antigens are involved in steering the immune responses to “protective” as opposed to “disease” state (Reiner et al., 1993; Reiner and Locksley, 1995; and Sjölander et al., 1998) and that antigenic composition of vaccines should be carefully considered for successful vaccination outcome, which is protection (Mendonça, 2016). In our study differences in antibody responses to individual glycoproteins were examined to investigate whether any of the glycoproteins may be related to “protection” as opposed to “disease” state caused by the vaccine and the virulent strains respectively. Examination of β-Glycerophosphate sodium salt hydrate induced against each glycoprotein after exposure to field and vaccine strains did not find a significant difference between the vaccine and field strains (Table 4). There was also a very poor correlation between antibody titers and microscopic tracheal lesion scores. A mammalian expression system was used here to generate recombinant viral glycoproteins because of its advantages over bacterial and insect cell expression systems in terms of maintaining native structure and post-translational modification of the glycoproteins, thus providing the best reflection of antigenicity and function (White and Wimley, 1999). HEK 293 T cell lines were used because of their known capacity for production of recombinant proteins in high yield (Lin et al., 2015). While ILTV gD, gE, gG, and gJ were expressed and purified successfully using small-scale transient gene expression in HEK 293 T cells, similar experiments failed to produce a purified gB. When a similar gene construct was used in baculovirus expression system, a protein of the expected size for gB could be detected in the lysates of the expressing insect cells but not in the cell culture supernatant (unpublished data). This suggests that failure to express gB may be due to an incorrect processing, inhibiting secretion. It is puzzling that the native gB signal peptide is functional in the host (chickens) but not in the mammalian expression system used in this study.
Acknowledgments
Introduction Wheat germ is known as “a natural nutrient treasure house and life source of human life” [1]. It is a crucial by-product in wheat processing industry and highly well-known for its nutritional value [2], as it contains proteins [3], carbohydrates, fatty acids, vitamins (e.g. tocopherol), dietary fibers [4] and functional phytochemicals (e.g. flavonoids, and glutathione) [5]. With gradual identification of the components and their related functions, wheat germ products have found wide application in pharmaceutical industries. Owing to high biocompatibility and significant biological activities, wheat germ oil has become one of the important ingredients in several medicinal and cosmetic formulations [6]. Wheat germ agglutinin is widely used for detecting cell surface sugar molecules to distinguish between malignant and normal cells [7]. Additionally, it was also applied for analyzing the morphological changes in erythrocytes during combing with cell surface receptors [8]. The total phenolic extract from wheat germ is used for producing nutrient drugs that can reduce oxidative stress [9]. Current studies mainly investigate the activities of wheat germ extracts that may be potentially applied for industrial purposes [10], and reports on the identification and structure-activity relationship of effective components in wheat germ extracts are limited. A recent study showed that water soluble glycoprotein in wheat germ extracts may affect immunity regulation, decrepitude deferment, and tumor inhibition [11]. However, the fine structure and physicochemical properties of the glycoprotein have not been determined.
Materials and methods
Results and discussion
Conclusions Wheat germ is a byproduct of flour production that contains various nutrients. Previous studies showed that the protein components of wheat germ water-soluble extracts possessed functions of decrepitude deferment, immunomodulation, and tumor inhibition, and can be used as a nutraceutical for preparation of functional foods. In this study, a novel glycoprotein, WGPII, with an average molecular weight of 14.5 kDa, was successfully extracted from the commercial wheat germ after a series of purification steps. The composition of WGPII was completely characterized. WGPII consists of 70.38% (w/w) proteins, in which glutamic acid was the predominant amino acid (75.08%, w/w). The carbohydrate component was also exhaustively interpreted to determine the precise monosaccharide composition and their connection with the proteins. The carbohydrate and proteins in the WGPII were linked by O-linkage. Interestingly, this novel glycoprotein was highly stable in aqueous solution at the concentration range of 0.1–1 mg/mL at room temperature, and the decomposition temperature could be as high as 320.3 °C. The MSD values showed that the elasticity index and macroscopic viscosity of WGPII increases first and then decreases with increase in concentration. This study improves our understanding of the structure and composition of glycoprotein WGPII from wheat germ, which will assist in investigating its therapeutic values and structure-activity relationship to utilize its potential application in pharmaceutical and food industries.