Endogenous myelin basic protein serum factors in lewis rats evidence for their heterogeneity and reactivity with anti myelin basic protein antibodies of different affinities
Day, E.D.; Varitek, V.A.; Paterson, P.Y.
Journal of the Neurological Sciences 49(1): 1-18
1981
ISSN/ISBN: 0022-510X
Accession: 005358166
MBP-SF, previously described as an endogenous myelin basic protein[MBP]-serum factor in Lewis rats with a suggested function as a neuroautotolerogen, appears not to be a single factor but a heterogeneous collection of serum factors (MBP-SF); they are most probably small fragments of MBP, each cross-reactive with a different region of the multideterminant parent molecule. The heterogeneity of the MBP-SF in any serum sample is defined and limited by the spectrum of binding affinities of the antibody populations, represented in a given reagent anti-MBP antiserum. Some samples of normal Lewis serum contain high affinity MBP-SF which coexist with low affinity anti-MBP antibodies; other sera show the reversed pattern, i.e., low affinity MBP-SF and high affinity antibodies. Additional sera have been found to contain MBP-SF of several different affinities. In time-course studies of rats sensitized to neuroantigen-adjuvant, a variety of MBP-SF and anti-MBP antibodies of different affinities may be observed in sequentially collected sera from a given animal. In no animal did any serum sample contain the full spectrum of MBP-SF. Although some MBP-SF increase temporarily during the 2nd wk after neuroantigen/CFA [complete Freund's adjuvant] sensitization, all MBP-SF tend to disappear in the 2nd wk, and to be replaced by anti-MBP antibodies of differing affinities 3-4 wk following sensitization.