Human IL-7 ELISA Kit

INTENDED USE

This Human Interleukin-7 ELISA Kit is to be used for the in vitro quantitative determination of human interleukin-7 (IL-7) concentrations in serum, plasma, cell culture supernatant, and other biological fluids. This kit is intended for LABORATORY RESEARCH USE ONLY and is not to be used in diagnostic or therapeutic procedures.

INTRODUCTION

Human IL-7 is 17.4 kDa protein containing six exons.  The gene has a length of approximately 33 kb and maps to chromosome 8q12-q13.  Expressed mouse IL-7 is a 25 kDa single-chain glycoprotein. Human (152 amino acids, 17.4 kDa) and murine IL-7 (129 amino acids) display a 60 percent sequence homology at the protein level, and both proteins contain three disulfide bonds that are essential for the biological activity of the molecule. The human IL-7 receptor is an integral, highly glycosylated membrane protein of 76 kDa that is expressed on activated T-cells, which has been designated as CD127.

IL-7 is produced predominantly by epithelial cells, especially keratinocytes and thymic epithelial cells, and is a nonredundant cytokine in thymic T-cell development.  IL-7 enhances survival and proliferation of T cell precursors in humans and mice and B cell precursors in mice. IL-7 also affects survival and proliferation of mature T cells, but not mature B cells, and is known to be a potent enhancer of T cell function and IFN-γ production.  IL-7 system deficiency in humans may cause severe combined immunodeficiency (SCID) syndrome.

IL-7 is acritical cytokine for normal T and B lymphopoiesis and is a mobilizer ofpluripotent stem cells and myeloid progenitors. IL-7 enhances T cell function and induces cytokine expression in monocytes.  Preclinical studies indicate that IL-7 is capable of accelerating murinelymphocyte regeneration following chemotherapy and bone marrowtransplantation, inducing anti-tumor effects in mice, and expandinganti-HIV-specific human T cells.  Because of the potent capability of IL-7 in T-lymphopoiesis augmentation, IL-7 may play a role in the immune reconstitution of T-cells during HIV infection, especially in the context of effective antiretroviral treatments.  IL-7 is elevated in untreated patients with advanced HIV disease and in those who fail highly active antiretroviral therapy (HAART), but is undetectable in HIV-infected patients who respond to HAART. Immune reconstitution is a critical issue in the treatment of HIV infection, and immune replacement therapy that relies on a variety of regulatory cytokines has been proposed to reconstitute the immune system function in HIV-infected patients. Thus, it is essential that continuedpreclinical and clinical research is performed to evaluate IL-7 as apotential therapy for leukopenia, bone marrow/stem cell transplantation,cancer, and HIV/AIDS. 

This IL-7 ELISA is a ready-to-use 3.5-hour solid phase immunoassay readily capable of measuring IL-7 levels in serum, plasma, cell culture supernatant, and other biological fluids in the range of 0 to 2000 pg/mL.  This assay has shown no cross-reactivity with other cytokines tested, and is expected to be used effectively for further investigations into the relationship between IL-7 and the various conditions mentioned.