Immunomodulatory effects of crx-527 on immune response against bcg-msp1c

Zakaria, Nor Munirah (2025) Immunomodulatory effects of crx-527 on immune response against bcg-msp1c. PhD thesis, Universiti Sains Malaysia.

PDF Download (10MB)

Abstract

Development of vaccines against malaria is crucial since malaria continues to be a serious worldwide health concern that affects millions of people each year. The development of recombinant vaccines using live vectors, such as Mycobacterium bovis BCG, has been extensively used to combat many infectious diseases, including malaria. Our group has previously demonstrated that innate immune cells, including macrophages bind to a recombinant BCG expressing the MSP-1C antigen of Plasmodium falciparum (BCG-MSP1C) through various toll-like receptors including TLR4. This reaction stimulates both innate and acquired immune responses by increasing host-pathogen interaction and presentation. However, the mechanism by which these TLRs enhance an immune response to BCG-MSP1C is still unknown. The current work used the TLR4 agonist (CRX-527) as a model has been conducted to assess the involvement of TLR4 in activating the innate and acquired immune response against BCG-MSP1C. In this study, mice (n=6) were divided into eight groups and injected with either PBS-T80, LPS, parent BCG, or BCG-MSP1C, with or without CRX-527 (0.5 mg/kg). Blood was drawn from the tail veins of mice before and 3 weeks after each immunisation. After the animals were sacrificed, the peritoneal macrophages and spleen were collected to prepare peritoneal macrophage and splenocyte cultures. ELISA was used to determine inflammatory cytokines (IL-1β, IL-10, IL-12p40, TNF-α) and nitric oxide (NO) in peritoneal supernatant and serum, as well as intracellular cytokines (IL-4 and IFN-γ) in splenocyte culture supernatant and serum. Total IgG and IgG subclasses (IgG1, IgG2a, and IgG2b) responses from mouse serum were also measured using ELISA, while protein expression in macrophages and splenocytes was determined using Western blot analysis and reverse transcriptase-polymerase chain reaction (RT-PCR) respectively. The results demonstrated that CRX-527 enhances inflammatory and intracellular cytokine production, NO production, IgG and IgG subclass response, and signalling protein expression. The increases were significant in BCG-MSP1C. In the IgG productions the IgG2a showed the highest productions of IgGs among the class with 2.728 ± 0.0069 OD, while in peritonel macrophage cytokine, IL-1β have the highest productions with 2261.09 ± 13.36 pg/mL and IL-12p40 serum cytokine 455.947 ± 0.1802 pg/mL. Protein expression of BCG-MSP1C also higheest in the p38 of peritoneal sample with 1.819 ± 0.0132 MRI. These findings suggested that CRX-527 acts as a booster for the enhancement of an immunological response to BCG-MSP1C, making it a suitable candidate for malaria vaccine development. More research is needed to understand the underlying mechanisms of how this CRX-527 adjuvant can improve the immune response to BCG-MSP1C

Item Type:	Thesis (PhD)
Uncontrolled Keywords:	Immunomodulatory
Subjects:	R Medicine R Medicine > RC Internal medicine
Divisions:	Kampus Kesihatan (Health Campus) > Pusat Pengajian Sains Kesihatan (School of Health Sciences) > Thesis
Depositing User:	MUHAMMAD AKIF AIMAN AB SHUKOR
Date Deposited:	15 Nov 2025 23:49
Last Modified:	16 Nov 2025 04:30
URI:	http://eprints.usm.my/id/eprint/63206

Actions (login required)

View Item