Identification of CD19 and CD20 Peptides for Induction of Antigen-Specific CTLs against B-Cell Malignancies

• Published in: Clinical cancer research 2005-02, Vol.11 (4), p.1629-1638
• Main Authors: BAE, Jooeun, MARTINSON, Jeffrey A, KLINGEMANN, Hans G
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Antigens, CD19 - chemistry; Antigens, CD19 - immunology; Antigens, CD20 - chemistry; Antigens, CD20 - immunology; Antineoplastic agents; B-Lymphocytes - immunology; B-Lymphocytes - pathology; Biological and medical sciences; CD4-Positive T-Lymphocytes - cytology; CD4-Positive T-Lymphocytes - immunology; CD4-Positive T-Lymphocytes - metabolism; CD8-Positive T-Lymphocytes - cytology; CD8-Positive T-Lymphocytes - immunology; CD8-Positive T-Lymphocytes - metabolism; Cell Line, Tumor; Cell Proliferation; Cytotoxicity, Immunologic - immunology; Hematological disorders; HLA-A2 Antigen - immunology; Humans; Immunotherapy; Interferon-gamma - secretion; K562 Cells; Medical sciences; Oligopeptides - immunology; Peptide-specific cytotoxic; Pharmacology. Drug treatments; Receptors, Complement 3d - immunology; Self-antigen; T lymphocytes; T-Lymphocytes, Cytotoxic - cytology; T-Lymphocytes, Cytotoxic - immunology; T-Lymphocytes, Cytotoxic - metabolism
• ISSN: 1078-0432; 1557-3265
• DOI: 10.1158/1078-0432.CCR-04-1612

The purpose of these studies was to develop immunogenic peptides derived from the CD19 and CD20 self-antigens for the induction of antigen-specific CTLs against B-cell malignancies. A total of seven peptides were designed and examined for their HLA-A2.1 affinity and immunogenicity. Of these peptides, we identified two highly immunogenic HLA-A2.1-specific peptides, CD19 150-158 (KLMSPKLYV) and CD20 188-196 (SLFLGILSV), which were capable of inducing peptide-specific CTLs. The CTLs displayed HLA-A2.1-restricted and antigen-specific cytotoxicity against Burkitt's lymphoma, chronic B cell leukemia, and multiple myeloma cell lines. The CD19 or CD20 peptide–specific CTL cytotoxicity was confirmed using HLA-A2.1 + T2 cells presenting the appropriate peptide. No cytotoxic activity was observed against T2 cells presenting the irrelevant MAGE-3 peptide or T2 cells alone. In addition, the CTLs displayed a significant ( P < 0.05) increase in cell proliferation and IFN-γ secretion (>830 ng/mL) following restimulation with HLA-A2.1 + /CD19 + /CD20 + tumor cells. The CTLs also displayed a distinct phenotype consisting of a high percentage of CD69 + /CD45RO + and a low percentage of CD45RA + /CCR7 + CD4 + or CD8 + T cells characteristic of effector memory cell population. Cyclic guanosine 3′,5′-monophosphate culture conditions using serum-free AIM-V medium containing human AB serum, recombinant human interleukin 2 (Proleukin) and CD3/CD28 Dynabeads were developed resulting in a 35-fold expansion of CD20 peptide–specific CTLs. The expanded CD20-CTLs retained their cytotoxic activity (28-49%) against the Burkitt's lymphoma cell line. In conclusion, we report here on the identification of novel immunogenic CD19 150-158 (KLMSPKLYV) and CD20 188-196 (SLFLGILSV) peptides that have immunotherapeutic potentials as peptide vaccines or targeted T-cell therapies for treating B-cell malignancies.