AMSBIO reports on a paper from the Malmberg Lab at Oslo University Hospital and the Norwegian Radium Hospital Institute for Cancer Research (Norway) that suggests a mechanism by which Natural Killer (NK) cell education operates through modulation of the lysosomal compartment under the influence of inhibitory receptor–ligand interactions.
Representative immuno-EM section showing staining with gold-particle coated anti-Chondroitin Sulfate-4 (CS-4) stub antibody of NK cells expressing non-self (left) or self (right) KIR. (Sectioning and staining performed for Malmberg Lab, Oslo University Hospital by Andreas Brech at the Norwegian Radium Hospital Institute for Cancer Research).
The research reveals that educated NK cells expressing self-MHC specific inhibitory killer cell immunoglobulin-like receptors (KIR) accumulate granzyme B and Chondroitin Sulfate-4 in dense-core secretory lysosomes that converge close to the centrosome. Secretory lysosomes are critical to the cytotoxic function of NK cells, so these changes illuminate the mechanisms by which they learn to respond to cells that might be a danger to the organism.
Natural Killer cells are lymphocytes that can kill tumor cells or virus-infected cells without requiring antibodies. NK cells express both activating and inhibitory receptors on their surface, and the function of NK cells is regulated by the delicate signaling balance between these two types of receptors.
William Hadlington-Booth - a business unit manager at AMSBIO said:
The Malmberg Lab researchers used our reagents and enzymes to detect one distinctive sulfation pattern of Chondroitin Sulfate, which helped them understand the process by which NK cells are “educated”. He added "This ground breaking research by the Malmberg Lab. demonstrates how our antibodies and enzymes work across species and tissues to detect subtle – but important - variations in glycosaminoglycans in the cellular and extracellular matrix".
AMSBIO is a leading global supplier of a highly purified Chondroitinase ABC enzyme (supplied as a protease-free, carrier-free format, with low endotoxin levels), as well as three associated monoclonal antibodies that recognise unsulfated, 4-sulfated and 6-sulfated Chondroitin and Dermatan Sulfate, following Chondroitinase ABC digestion of proteoglycans or perineuronal nets.