pre-immune serum came out positive
Michael L. Sullivan
mlsulliv at facstaff.wisc.edu
Thu Feb 15 10:57:42 EST 2001
Regardless of immunity that may arize after immunization, I think we'd all
agree that it is prudent to look at preimmune serum prior to immunizaion.
Afterall, in the original post, the concern was that pre-immune seemed to
be reactive to as many proteins as immune. Checking serum before
immunization may not solve all the problems, but it will avoid starting out
>Henk Veldman <H.Veldman-2 at neuro.azu.nl> wrote:
>:"Michael L. Sullivan" schreef:
>:> Well, your rabbit was probably exposed to something that immunized it
>: proteins in your extract.
>:> What were you using the antibody against, some sort of crude extract
>: was the extract made from? I know that plants and yeast often have proteins
>: that cross react with antibodies in pre-immune serum. For plants, it is
>: related to diet, which contains plant materials, and for yeast, I hear it's
>: because rabbits often have yeast infections. I don't know how prevalent
>: reaction is with other types of extracts.
>:> It is a good idea to test preimmune serum from rabbits *before*
>: with your antigen. When. . . <......>
>:Even when the preimmune serum is clean, the immunization procedure, usually
>: with some kind of adjuvant, can induce immunity against unwanted antigens.
>: Most notably quite high titers might be raised against keratins from human
>: skin that are around everywhere and are also difficult to avoid
>: protein preparations for SDS-PAGE / western blotting.
>:Such antisera can be perfectly OK for some applications such as
>: immunohistochemistry, otherwise affinity purification may be necessary.
>Absolutely correct. Anyone who ever tested preimmune serum vs
>immune against irrelevant antigen vs immune against the antigen
>assayed can confirm this. Adjuvants boost immune response
>against _all_ antigens.
>That is exactly why using preimmune serum, even when from
>the same animal, is in fact not a very thorough control. I've seen
>a number of screw ups where claimed "specific something"
>persisted upon serum/IgG immunodepletion on an antigen
>column. Of course, doing such right controls is difficult so
>almost nobody bothers with them and usually a non-immune
>serum from a different animal is considered to be an accurate
> - Dima
Michael L. Sullivan, Ph.D
U.S. Dairy Forage Research Center
1925 Linden Drive West
Madison WI, 53706
(608) 264-5144 Phone
(608) 264-5147 Fax
More information about the Methods