Mutations in the H, F, or M Proteins Can Facilitate Resistance of Measles Virus to Neutralizing Human Anti-MV Sera

Table 4

Transient neutralization study of the six escape mutants selected for further study.

Virus	Serum 1	Serum 2	Serum 3	Serum 5	SSPE serum
Halle (+ve control)	1/80	1/80	1/400	1/40	1/2400
Halle-SLAM 1.2	1/20				1/600
Halle-SLAM 2.3		1/20			1/1200
Halle-SLAM 5.1				1/20	1/600
Halle-CD46 1.2	1/10				1/600
Halle-CD46 1.3	1/20				1/600
Halle-CD46 3.3			1/50		1/600

The standard Plaque Reduction Neutralization Test (PRNT₅₀) was used to give a measure of the neutralizing capacities of anti-MV sera regarding the different mutants. The neutralizing capacity of four sera (sera 1, 2, 3, and 5) obtained from persons immunized against measles virus and one serum from a SSPE patient was studied for the different mutants relative to (non-mutated) Halle. The PRNT₅₀ values obtained for each virus are indicated.