Related Experiment Video
Updated: Feb 26, 2026

Enrichment of Bacterial Lipoproteins and Preparation of N-terminal Lipopeptides for Structural Determination by Mass Spectrometry
Published on: May 21, 2018
Structure-function relationships of protein-lipopeptide complexes and influence on immunogenicity
Acep R Wijayadikusumah1,2, Lucy C Sullivan1, David C Jackson3,4,5
1Department of Microbiology and Immunology, The University of Melbourne, at The Peter Doherty Institute for Infection and Immunity, 792 Elizabeth St, Melbourne, VIC, 3000, Australia.
The lipopeptide R4Pam2Cys enhances immune responses to antigens like ovalbumin (OVA), showing comparable antibody production to Freund's adjuvant. Stereoisomer substitution impacts T cell responses but not adjuvant efficacy.
Area of Science:
- Immunology
- Vaccinology
- Biochemistry
Background:
- Lipopeptides are potent immune stimulants.
- Adjuvants are crucial for vaccine efficacy.
- R4Pam2Cys is a novel lipopeptide adjuvant.
Purpose of the Study:
- To evaluate R4Pam2Cys as an adjuvant for humoral and cell-mediated immunity.
- To compare R4Pam2Cys with alum and complete Freund's adjuvant (CFA).
- To investigate the role of stereoisomers in R4Pam2Cys adjuvant activity.
Main Methods:
- Formulation of ovalbumin (OVA) with R4Pam2Cys, alum, or CFA.
- Measurement of antibody titers and avidities.
- Assessment of IgG class-switching.
- Dendritic cell maturation assays.
- CD8+ T cell response analysis.
- Protease resistance assays.
Main Results:
- R4Pam2Cys significantly enhanced antibody titers compared to alum, comparable to CFA.
- Antibody avidities followed the hierarchy CFA > R4Pam2Cys = alum.
- R4Pam2Cys promoted IgG1 class-switching.
- D-amino acid substitution did not affect adjuvant efficacy or dendritic cell maturation but slightly impaired CD8+ T cell responses.
- Both L- and D-forms were trypsin-resistant.
Conclusions:
- R4Pam2Cys is a potent adjuvant that elicits strong humoral and cell-mediated immune responses.
- Stereoisomer composition influences T cell responses, suggesting differential effects on antigen processing.
- R4Pam2Cys exhibits protease resistance, indicating stability.
More Related Videos
Related Concept Videos
Protein-protein Interfaces
Protein Complex Assembly
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Conjugated Proteins
Nucleoproteins are protein complexes that contain nucleic acids, categorized as deoxyribonucleoproteins (DNPs) or ribonucleoproteins (RNPs) respectively. The nucleosome is a typical example of a DNP where nuclear DNA is associated with histone proteins. The major antigen for the Covid-19 virus SARS-CoV is an RNP that is critical...
Formation of Lipopolysaccharides
Antibody Structure
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
Protein Complexes with Interchangeable Parts
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order...

