Wyatt Technology’s MALS instruments characterize novel malaria vaccine candidates

Wyatt Technology has been chosen by the Malaria Vaccine Development Branch (MVDB) of the National Institute of Allergy and Infectious Diseases (NIAID) for its instruments to characterize the recombinant protein vaccines it produces.

Wyatt’s novel Multi-Angle Light Scattering (MALS) instruments were found to facilitate MVDB’s understanding of purity, identity and aggregation states of recombinant protein vaccine candidates after they were separated by Size Exclusion Chromatography (SEC).

Malaria remains one of the world’s deadliest diseases for people living in the tropics, particularly in Africa. Globally, malaria causes more than 1 million deaths each year with approximately 60% of these deaths occurring in the poorest 20% of the total global population. Malaria kills one child under five years of age every 30 seconds. Unfortunately, malaria parasites have developed a variety of mechanisms to evade host immune responses, thus making the development of a successful vaccine very challenging. The Malaria Vaccine Development Branch of NIAID was established in 2001 at the Institute’s Rockville, Maryland research facility. MVDB is an 8,000-square-foot, state-of-the-art biotechnology laboratory designed to develop, produce and characterize pilot lots of promising malaria vaccine candidates based on recombinant proteins. Those vaccine candidates are intended for use in Phase I and II human trials.

For this particular application, the solution profile of a candidate antigen was analyzed using analytical SEC with on-line MALS, Refractive Index (RI) and UltraViolet (UV) detection. A High Performance Liquid Chromatography (HPLC) and a PhotoDiode-Array PDA detector were connected in series to Wyatt’s DAWN EOS and Optilab RI detectors run by Wyatt’s ASTRA software suite. An isocratic elution at 0.5 mL/min was performed using a TSK gel G3000PWxl column and a TSK gel Guard PWxl column with 0.04mM KH2PO4, 2.97mM Na2HPO4•7H2O, 308mM NaCl, 0.5M urea, pH 7.4, 0.02% sodium azide for mobile phase.

The SEC-MALS results clearly demonstrated that the solution state of the vaccine candidate was comprised of three populations, namely monomer, dimer and tetramer. This fact was later verified by boundary sedimentation equilibrium studies. A copy of the new application note, entitled “Novel Malaria Vaccine Candidates” is available from Wyatt.