At Absolute Antibody we have developed a collection of recombinant engineered antibodies against clinically relevant proteins, including homologues of current therapeutic targets. We can match the antibody species to the host organism and tailor the effector function, similar to how pharmaceutical companies develop human therapeutics.
Antibodies against proteins involved in co-stimulation and other aspects of immune cell regulation are of particular interest to therapeutics developers. Some have already entered the clinic, with more in the development pipeline. However, many aspects of immune cell signalling are still unknown, and researchers require ever more advanced tools to tap into this potential.
At Absolute Antibody, we use recombinant technology to provide superior monoclonal antibody reagents at competitive prices. In particular we can modify antibody species and isotype for greater flexibility in vivo, for example we can readily generate mouse-anti-mouse or rat-anti-rat antibodies.
Why go recombinant?
Because of their recombinant manufacture our antibodies show minimal batch-to-batch variability and have potential for customisation. We can convert any antibody into any format allowing us to offer each specificity in a range of species, isotypes and subtypes. This means our customers may ‘build’ an antibody to best suit their experiment.
Choose primary antibody format to suit your secondary reagent
Choose antibody species to be compatible with your model organism
Choose antibody isotype to investigate your chosen host responses (includes IgM and all IgG subtypes)
Choose from a range of custom engineering options such as our Fc Silent format with reduced FcR binding to remove Fc receptor function, or other such formats found in the literature (e.g. IgG1-LALA, IgG1-D265A)
Choose one of our listed antibodies, or apply our recombinant technology to your own clone. All our antibody services are royalty-free.
Although the immune checkpoint protein B7-H1/PD-L1 is a commonly used cancer biomarker, controversy remains over the predictive and prognostic utility of immunohistochemical methods. Download our white paper which shows that we can reliably measure B7-H1/PD-L1 in conditioned media supernates and cell lysates from a number of cancer cell lines.
Data from our white paper indicate that:
We can reliably measure B7-H1/PD-L1 in a number of human cancer cell lines
Soluble B7-H1/PD-L1 expression levels are coincident with loss of PTEN tumor suppressor or increased activation of the phosphoinositide 3-kinase pathway
The immune system fights off pathogens, but this defensive force can be pathogenic itself when hyperactive, resulting in autoimmune diseases such as lupus and multiple sclerosis. Consequently, the body has developed multiple mechanisms to suppress the immune system when necessary.
One method of immunosuppression is the PD-1 pathway. This pathway is activated in response to the mobilization of the immune system. The receptor PD-1 is expressed on the surface of activated lymphocytes. Similarly, its ligand, PD-L1, is expressed by antigen-presenting cells in response to cytokine signaling. When PD-L1 is bound to PD-1, downstream signaling undoes the phosphorylation events associated with activation, thereby reverting lymphocytes to an inactive state [1, 2].
Tumor cells take advantage of the PD-1 pathway to evade the immune system . Consequently, many pharmaceutical companies have been developing drugs to inhibit PD-1 and PD-L1. In clinical trials, many patients have shown strong responses to these therapies [4-10]. For these drugs to be most effective, a high number of CD8+ T cells must already be at the tumor site, ready to be mobilized after inhibition of the PD-1 pathway .Recent investigations have uncovered promising methods of increasing the efficacy of PD1 inhibitors. One method is combining PD1 inhibitors with other drugs, such as HDAC inhibitors  and anti-CTLA4 antibodies . Another method is using biomarkers to predict response to therapy [13,14]. Recent work has also suggested that GSK3 inhibitors can enhance effects of immunotherapy .Though these results have been encouraging, several challenges remain, including the mitigation of autoimmune effects and how to overcome drug resistance.
1. Ohegbulam et al. (2015) Human cancer immunotherapy with antibodies to the PD-1 and PD-L1 pathway. Trends Mol Med. 21:24-33.
2. Haanen, J. (2013) Immunotherapy of Melanoma. EJC Suppl 11:97-105.
3. Yao et al. (2013) Advances in targeting cell surface signaling molecules for immune modulation. Nat Rev Drug Discov. 12:130-146.
4. Topalian, S. et al. (2012) Safety, activity, and immune correlates of anti-PD-1 antibody in cancer. N. Engl. J. Med. 366:2443-2454.
5. Hamid, O. et al. (2013) Safety and tumor responses with lambrolizumab (anti-PD-1) in melanoma. N. Engl. J. Med. 369:134-144.
6. Topalian, S. L. et al. (2012) Safety, activity, and immune correlates of anti-PD-1 antibody in cancer. N. Engl. J. Med. 366:2443–2454
7. Brahmer, J. R. et al. (2012) Safety and activity of anti-PD-L1 antibody in patients with advanced cancer. N. Engl. J. Med. 366:2455–2465
8. Hamid, O. et al. (2013) Safety and tumor responses with lambrolizumab (anti-PD-1) in melanoma. N. Engl. J. Med. 369:134–144
9. Wolchok, J. D. et al. (2013) Nivolumab plus ipilimumab in advanced melanoma. N. Engl. J. Med. 369:122–133
10. Topalian, S. L. et al. (2014) Survival, durable tumor remission, and long-term safety in patients with advanced melanoma receiving nivolumab. J. Clin. Oncol. 32:1020–1030
11. Tumeh, P. et al. (2014) PD-1 blockade induces responses by inhibiting adaptive immune response. Nature. 515:568-71.
12. Woods, D. et al. (2015) HDAC inhibition upregulates PD-1 ligands in melanoma and augments immunotherapy with PD-1 blockade. Cancer Immunol Res 12:1375-85.
13. Chakravarti, N., & Prieto, V. G. (2015). Predictive factors of activity of anti-programmed death-1/programmed death ligand-1 drugs: immunohistochemistry analysis. Translational Lung Cancer Research, 4:743–751.
14. Barak, V. et al. (2015) Assessing response to new treatments and prognosis in melanoma patients, by the biomarker S-100B. Anticancer Res. 35:6755-60.
15. Taylor, A. et al. (2014) Glycogen synthase kinase 3 inactivation drives T-bet-mediated downregulation of co-receptor PD-1 to enhance CD8+ cytolytic T cell responses. Immunity 44:274-86.