Immunoreactivity against linear epitopes of parvovirus B19 structural proteins. Immunodominance of the amino-terminal half of the unique region of VP1.

Three peptides corresponding to the 2-100 amino acids of VP1 unique sequence (VP1-F1), to the 99-227 amino acids of VP1 unique sequence (VP1-F2) and to the 237-781 amino acids of VP1 protein common to VP2 (VP1-F3 = VP2) were produced by prokaryotic expression. The three peptides, which span the entire VP1 structural protein of parvovirus B19 and also the entire VP2 protein, were used to evaluate the immunoreactivity against linear epitopes of these fragments in a large number of serum samples taken in different clinical situations with regards to B19 infection and in some commercial preparations of aspecific immunoglobulins. The data demonstrated that the specific VP1-F1 fragment, corresponding to the amino-terminal half of the VP1 unique region, is immunodominant and can elicit a long lasting immune response in comparison with VP1-F2 and VP1-F3 = VP2. Data regarding the presence of specific IgG to the three fragments in commercial preparations of immunoglobulins demonstrated that the dominant immune response was also against VP1-F1 linear epitopes while IgG against VP1-F2 and IgG against VP1-F3 = VP2 could be found only in high concentrations of Ig preparations. The reported data can be useful as a basis for the development of a B19 recombinant vaccine. Copyright 2000 Wiley-Liss, Inc.