Purification, Identification and Functional Analysis of a Novel Immunomodulatory Peptide from Silkworm Pupa Protein

• Published in: International journal of peptide research and therapeutics Vol. 26; no. 1; pp. 243 - 249
• Main Authors: Li, Zhiyong, Zhao, Shan, Xin, Xiangdong, Zhang, Bei, Thomas, Attaribo, Charles, Asakiya, Lee, Kwang Sik, Jin, Byung Rae, Gui, Zhongzheng
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.03.2020; Springer Nature B.V
• Subjects: Amino acid sequence; Animal Anatomy; Biochemistry; Biomedical and Life Sciences; Bombyx mori; Chromatography; Cyclin D1; Cyclin-dependent kinase; Cyclin-dependent kinase 4; Cyclin-dependent kinases; Histology; Hydrolysates; Immunomodulation; Interleukin 6; Life Sciences; Liquid chromatography; Mass spectrometry; Mass spectroscopy; Molecular Medicine; Molecular weight; Morphology; Pepsin; Peptides; Pharmaceutical Sciences/Technology; Pharmacology/Toxicology; Polymer Sciences; Proteins; Pupae; Spleen; Subtilisin; Trypsin; Ultrasound; Identification; Purification; Silkworm pupa protein; Immunomodulatory peptide
• ISSN: 1573-3149; 1573-3904
• DOI: 10.1007/s10989-019-09832-4

In this study, we isolated and characterized an immunomodulatory peptide from silkworm ( Bombyx mori ) pupa protein hydrolysates. Ultrasound-pretreated hydrolysates were prepared by alcalase digestion and their pro-proliferative activity was assessed with the splenic lymphocyte proliferation assay. Peptide fractions exhibiting the highest activity were purified by Sephadex-G100 and -G15 gel filtration chromatography. The structure of the purified peptides was analyzed using Liquid Chromatography Electrospray Ionisation Tandem Mass Spectrometry (LC–ESI–MS/MS); their digestive stability and their effects of the expression on immune-related cytokines were also evaluated. We purified a novel immunomodulatory peptide with a molecular weight of about 441.06 Da. The amino acid sequence was Asp-His-Ala-Val (DHAV). The splenocyte proliferation rate was 91.1% (P < 0.05) in the presence of 100 µg/mL purified peptide. DHAV was stable in the presence of the gastrointestinal proteases pepsin and trypsin, and stimulated the expression of immune-related factors including interleukin-6 and -12, nuclear factor-κB, cyclin D1, and cyclin-dependent kinase 4. Thus, DHAV purified from silkworm pupa protein hydrolysate has immunomodulatory activity and potential therapeutic value.