Anti-Idiotypic Antibody Mimics HMW-MAA (clone MK2-23) (CAT#: PABZ-072)

Figure 1 Level of anti–anti-idiotypic antibodies in sera from mice immunized with MK2-23-IL-2 fusion protein.

A, mice (n = 5 per group) were immunized on day 0 with MK2-23-IL-2 fusion protein and sera were harvested 1 and 2 weeks after priming. Anti–anti-idiotypic antibodies of the IgM subclass in 1-week sera (top) and of the IgG subclass in 1-week (middle) and 2-week (bottom) sera, were detected by ELISA with mAb MK2-23 F(ab')2 fragments (1 μg per well). Bound antibodies were detected by sequential incubation with HRP-conjugated anti-mouse IgM or IgG antibodies and with orthophenylenediamine. B, mice (n = 5 per group) were immunized on days 0, 28, and 84 with MK2-23-IL-2 fusion protein, mAb MK2-23 + IL-2, chMK2-23 + IL-2, KLH-MK2-23-IL-2, or KLH-MK2-23 + IL-2, and sera were harvested 1 week after the last immunization. Anti–anti-idiotypic antibodies were detected by RIA with ¹²⁵I-labeled anti-mouse IgG xenoantibodies, and were quantitated as cpm using a gamma counter. Columns, means of the sera dilution giving 50% of the maximal binding to mAb MK2-23; bars, FSD. ***, P < 0.001 versus mAb MK2-23 + IL-2; ##, P < 0.01 versus chMK2-23 + IL-2.

Wang, X., Ko, E. C., Peng, L., Gillies, S. D., & Ferrone, S. (2005). Human high molecular weight melanoma-associated antigen mimicry by mouse anti-idiotypic monoclonal antibody MK2-23: enhancement of immunogenicity of anti-idiotypic monoclonal antibody MK2-23 by fusion with interleukin 2. Cancer research, 65(15), 6976-6983.

Figure 2 Effect of the dose of anti-id mAb MK2-23 on its ability to induce anti-HMW-MAA antibodies in syngeneic hosts.

Sera were harvested on day 42 (solid) from BALB/c mice (4/group) immunized with 5, 50 or 500 μg/injection of anti-id mAb MK2-23 conjugated to KLH and mixed with CFA on day 0, with IFA on day 14 and with PBS on day 28. Sera (100 μL/well) were incubated with melanoma cells Colo 38 (2 x 10⁵ cells/well) in a microtiter plate for 2 hr at 4 °C. Following three washings with PBS ¹²⁵I-anti-mouse IgG Fc xenoantibodies (1 x 10⁵ cpm) were added to each well. Incubation was continued for an additional 2 hr at 4 °C. Cells were then washed five times with PBS and dried. Bound radioactivity was measured in a gamma counter. Results are expressed as mean ± SD of the cpm/2 x 10⁵ cells obtained with sera from four mice in each group. Preimmune sera (lateral-cut) were used as controls.

Ferrone, S., Chen, Z. J., Liu, C. C., Hirai, S., Kageshita, T., & Mittelman, A. (1993). Human high molecular weight-melanoma associated antigen mimicry by mouse anti-idiotypic monoclonal antibodies MK2-23. Experimental studies and clinical trials in patients with malignant melanoma. Pharmacology & therapeutics, 57(2-3), 259-290.