As an example of the power of UltraPlex technology, we rapidly assembled a new panel measuring 4 specific markers. Development of the panel takes 2—3 weeks and staining of individual tumor sections was carried out using our standard protocol of one antigen retrieval step followed by our standard two-step, two-hour staining procedure.
Use of vascular endothelial markers such as CD31 can provide an objective quantitation of neovascularization. Neovascularization of tumors as shown by a high level of microvascular density is associated with metastasis and worse prognosis in tumors such as breast cancer. CD31 staining of FFPE tonsil sections (above, left) demonstrates clear staining of the blood vessel lumen. In contrast, CD31 staining of the triple negative breast cancer (TNBC) biopsy to the right shows staining in the vessel lumen but also of multiple vascular spheres throughout the tissue. Assessment of proliferative index as measured by nuclear staining using Ki-67 has been shown to correlate with more aggressive tumors. High levels of Ki-67 are clearly seen in the TNBC section. Finally, antibodies specific for CD4 and CD8 T cells were included within the 4-plex panel as an example of measurement of immune infiltration, but measurement of activated granzyme B positive CD8 T cells or CD4+FoxP3+ T reg cells is equally simple.
Using multiplex technology where rearranging panels and inserting new markers is simple and rapid, allows researchers to quickly develop and test new hypotheses using tiny amounts of biopsy material as well as monitor the effects of drugs on multiple parameters using in-treatment biopsies.