Vaccination with spermine binding protein (p25) peptide provides effective immunotherapy against prostate tumors

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Presentation Time: 02:15 PM - 03:30 PM
Poster Board Number: B204
Abstract ID: 4373

Presenting Author:
Isabella Haslinger Johnson , Student at Western Reserve Acad.

Abstract:

Objectives: We had two objectives: 1) To evaluate the therapeutic potential of a novel spermine binding protein (p25 99-118) peptide vaccine in FVB mice inoculated with MyC-CaP prostate cancer cells, with a specific focus on its effects on tumor progression and survival rate; and 2) To investigate the immunomodulatory effects of the p25 99-118 vaccination, conducting an  analysis of the resultant alterations in immune cell phenotypes.

Methods: Myc-CaP cells were injected intraperitoneally into FVB mice. Upon the initial detection of palpable tumors in any mouse, p25 99-118 emulsified in Complete Freund's Adjuvant was administered and tumor progression assessed. Prostate tumors were excised, fixed, and embedded in paraffin. Tissue sections were then processed for antigen retrieval and immunohistochemical analysis targeting the CD3+ markers was employed.

Results:Vaccination with p25 99-118 provides therapy against transplantable Myc-CaP mouse prostate tumors in male FVB mice. A noteworthy observation was the absence of CD3+ T cell infiltration in the control group treated solely with CFA. In contrast, the vaccinated mice displayed a pronounced presence of CD3+ T cells within their tumor microenvironment.

Conclusions: Two key conclusions emerge: 1) The p25 99-118 vaccine effectively slows the growth of Myc-CaP prostate tumors in FVB mice; 2) The presence of CD3+ T cells in the tumor microenvironment of vaccinated mice signifies a vaccine-driven T cell response.