Hi Richard, Years ago I did a Paper with David Tacha on bulk staining.(JR
of Histotechnology March 1990) We prediluted several antibodies and kept
them at 4degress C.
I also used a factor 8 over and over that I had diluted 3-4 years
prior and and would retest every yeat . I
added thimerosal, and yes it was still working great. AT one one the
National Meeting I went to I think in 1992, wasn't it you who had all your
antibodies stored at 4 degrees?
Marianne Brown




On Tue, 2 Mar 1999, Richard Cartun wrote:

> I was told two days ago that we ran out of mAb B72.3 (tumor-associated
>glycoprotein 200).  Before I ordered new antibody I searched our
>refrigerator hoping to find a sample that we could use until the
>replacement arrived.  I found a large (by antibody standards) bottle
>containing 20 mLs of mAb B72.3 that we received on 6/20/1989 (almost 10
>years ago!) from a company in Stoughton, MA.  I decided that I would
>evaluate it in case it still worked.  Therefore, I prepared the following
>dilutions:
>
>  1:10                        0.9 mL diluent + 100 microliters of mAb
>  1:100                      0.9 mL diluent + 100 microliters from 1:10
>  1:1,000                   0.9 mL diluent + 100 microliters from 1:100
>  1:10,000                 0.9 mL diluent + 100 microliters from 1:1,000
>  1:100,000               0.9 mL diluent + 100 microliters from 1:10,000
>  1:1,000,000            0.9 mL diluent + 100 microliters from 1:100,000
>
> and applied them to sections of our positive control (lung
>adenocarcinoma) and allowed the slides to incubate overnight at RT.
>Normally, I would evaluate a mAb at just three dilutions: 1:100; 1:1,000
>and 1:10,000, but I seemed to remember that this antibody had a high
>titer.  Today, when I finished the slides with LSAB+ and DAB+ (DAKO
>Corporation) I was surprised to see that not only did the antibody still
>work, it gave some immunoreactivity at 1:1,000,000!   However, I selected
>1:1,000 as the optimal dilution for overnight incubation.  This translates
>into a concentration of .02 micrograms per mL according to the label which
>states, "20 micrograms/mL".
>
> Please remember that the performance characteristics of this antibody are
>very unusual, but I thought you might find this story interesting.  Oh, by
>the way, does anyone need any B72.3 mAb?
>
> Rich Cartun
> rcartun@harthosp.org
>
>