My first UW vaccine trial

[jojo]

Simple question above....

[SaraD]

has anyone heard concerns about a cancer vaccine making the immune system resistant or tolerant to the cancer? ive spoken to my science friends and my oncologist who say this is a big concern with peptide vaccines. i also saw a phase I trial specialist at u. colorado who recommended against the HER2 vaccines given at u. washington (seattle) for that reason. she said it could make the immune system tolerant, and that t cells from vaccinated patients have been shown to not be able to kill her2 positive tumors anymore. thoughts?

[Marcel]

Dear SaraD:

As I have just returned from a follow-up visit to UW to find your post, I asked the lead physician, Dr. Nora Disis, to comment on it, and received the following reply:

<<I have not seen any data like this. The majority of our subjects have
developed immunity to HER2 after vaccination and we have published that
those peptide specific T cells can kill HER2 + tumors. Publications that
people may be interested in that describe these findings are:

Knutson, K.L., Schiffman, K., and Disis, M.L.: Immunization with a HER-2/neu
helper peptide vaccine generates HER-2/neu CD8 T cell immunity in cancer
patients. J. Clin. Investigation. 107:477-484, 2001

Disis, M.L., Gooley, T.A., Rinn, K., Davis, D., Peipkorn, M., Cheever, M.A.,
Knutson, K.L., and Schiffman, K.: Generation of T cell immunity to the
HER-2/neu protein after active immunization with a HER-2/neu peptide based
vaccine. J. Clin Oncol, 20(11): 2624-2632, 2002

Knutson, K.L. and Disis, M.L.: Diversity of the T cell population responding
to a dominant HLA-A2 epitope of HER-2/neu in an ovarian cancer patient.
Human Immunology, 63 (7): 547-557, 2002.

This last publication describes the diversity of the killer T cell response
generated. These are just a few of many papers we have published on the
immune response to HER2 after vaccine (see our website
www.tumorvaccinegroup.org). In fact, Dr. Salazar is preparing a paper now
demonstrating that immunity persists for years after vaccination. We have
several patients from these initial studies who still have vigorous
responses to HER2, now over 7 years after vaccination!

Since our group has immunized dozens of patients with HER2 peptides I think
if there were such a phenomenon we would have seen it. Also- I am pretty
current with the results of most studies in the field and have not heard of
this as a major problem with other vaccines targeting other proteins. It
would be great to know where to find the information you talked about.>>