*1.7.1 Small secreted glycoprotein of EBOV*

Small secreted glycoprotein (ssGP) is translated from part of mRNA. It is nonstructural and generated when two adenosines are combined or one is deleted during transcription [50]. The ssGP has monomeric structure which has identical 295 amino acids from starting point with secreted GP and full length GP but they vary at the C-terminus of the full length glycoprotein [51]. The host ADAM17 metalloprotease enzyme is responsible to generate ssGP. The antibodies that neutralize the viral glycoproteins are quickly blocked by the secreted complex GP [14]. This complex plays a key function in the virus pathogenesis. In spite of extensive necrosis and massive virus production, it therefore contributes to less inflammatory reaction seen during the infection [14]. When the EBOV enters the host cell,

**Figure 4.** *Biosynthesis of glycoproteins of EBOV [45].*

the small secretary glycoprotein neutralizes the host cell neutrophils through CD16b and resulting in lymphocyte death and further vascular dysregulation [52].

## *1.7.2 Secreted or soluble glycoprotein and delta peptide of EBOV*

The soluble glycoprotein (sGP) is a non-structural protein with a single frame and has total 364-372 residues. At the N-terminal, 295 residues which also include the signal sequence are similar with full length GP. It differs in the length of C-terminal sequences [46, 50]. The formation of sGP is from Precursor (pre-sGP). Unedited mRNA is frequently produced from infected cells which results in the formation of precursor (pre-sGP). Precursor (pre-sGP) is cleaved by the furin protein to produce sGP and delta peptide [46, 50]. The orientation of sGP is antiparallel and linked together by disulfide bonding. It possesses dimerization between amino and carboxy groups as shown in **Figure 5**. The sGP plays a role in the evasion of humoral immune response by absorbing elicited antibodies. It also predicted to be involved in interaction with neutrophils of the host cells and their neutralization [53].
