Mouse IL-2(Interleukin 2) ELISA Kit

Purpose: Antibody-drug conjugates and small-molecule-drug conjugates have been proposed as alternatives to conventional anticancer cytotoxic agents, with the potential to deliver bioactive payloads to the site of disease, helping spare normal tissues. Experimental Design: Here, we describe a novel small-molecule-drug conjugate, based on a high-affinity ligand specific to carbonic anhydrase IX. The product featured a peptidic linker, suitable for cleavage in the tumor extracellular environment, and monomethyl auristatin E as cytotoxic payload. Results: A potent anticancer activity was observed in nude mice bearing SKRC-52 renal cell carcinoma xenografts, but no durable complete responses could be observed in this model. However, when the product was administered together with L19-IL2 (a clinical-stage fusion protein capable of delivering IL2 to the tumor neovasculature), all treated mice in the combination group could be rendered tumor free, in a process that favored the influx of natural killer cells into the tumor mass. The combination of L19-IL2 and the new small-molecule-drug conjugate also eradicated cancer in 100% of immunocompetent mice, bearing subcutaneously grafted CT26 colorectal cancer cells, which stably expressed carbonic anhydrase IX. Conclusions: These findings may be of clinical significance, because carbonic anhydrase IX is overexpressed in the majority of clear cell renal cell carcinomas and in approximately 30% of colorectal cancers. The targeted delivery of IL2 helps potentiate the action of targeted cytotoxics, leading to cancer eradication in models that cannot be cured by conventional chemotherapy. (C) 2018 AACR.

Vaccines that confer protection through induction of adaptive T-cell immunity rely on understanding T-cell epitope (TCE) evolution induced by immune escape. This is poorly understood in tuberculosis (TB), an ancient, chronic disease, where CD4 T-cell immunity is of recognized importance. We probed 905 functionally validated, curated human CD4 T cell epitopes in 79 Mycobacterium tuberculosis (Mtb) whole genomes from India. This screen resulted in identifying 64 mutated epitopes in these strains initially using a computational pipeline and subsequently verified by single nucleotide polymorphism (SNP) analysis. SNP based phylogeny revealed the 79 Mtb strains to cluster to East African Indian (EAI), Central Asian Strain (CAS), and Beijing (BEI) lineages. Eighty-nine percent of the mutated T-cell epitopes (mTCEs) identified in the 79 Mtb strains from India has not previously been reported. These mTCEs were encoded by genes with high nucleotide diversity scores including seven mTCEs encoded by six antigens in the top 10% of rapidly divergent Mtb genes encoded by these strains. Using a T cell functional assay readout, we demonstrate 62% of mTCEs tested to significantly alter CD4 T-cell IFN gamma and/or IL2 secretion with associated changes in predicted HLA-DR binding affinity: the gain of function mutations displayed higher predicted HLA-DR binding affinity and conversely mutations resulting in loss of function displayed lower predicted HLA-DR binding affinity. Most mutated antigens belonged to the cell wall/cell processes, and, intermediary metabolism and respiration families though all known Mtb proteins encoded mutations. Analysis of the mTCEs in an SNP database of 5,310 global Mtb strains identified 82% mTCEs to be significantly more prevalent in Mtb strains isolated from India, including 36 mTCEs identified exclusively in strains from India. These epitopes had a significantly higher predicted binding affinity to HLA-DR alleles that were highly prevalent in India compared to HLA-DR alleles rare in India, highlighting HLA-DR maybe an important driver of these mutations. This first evidence of region-specific TCE mutations potentially employed by Mtb to escape host immunity has important implications for TB vaccine design.