The effects of chronic inflammatory disorders and storage lesions on cytokine levels in blood transfusion products

Abstract

Whole blood donated for transfusion is processed into four blood products, namely Red Cell Concentrates (RCCs), Fresh Frozen Plasma, Buffy Coats (BCs), and Platelet Concentrates which are obtained by further processing of BCs. These blood products are then given to vulnerable patient cohorts such as anaemic, cancer or post-operative patients requiring RCCs. However, these blood products may contain biomolecules such as inflammatory mediators that may cause adverse yet often overlooked effects in the recipient. Chronic inflammation is characteristic of numerous diseases such as cardiovascular diseases, cancer, type 2 diabetes, rheumatoid arthritis, inflammatory bowel disease, asthma and psoriasis. Such diseases elevate pro-inflammatory cytokines including Interleukin (IL)-1, IL-6 and Tumour Necrosis Factor (TNF)- alpha in the blood. Moreover, pro-inflammatory cytokines also accumulate in blood products during storage, mainly as a result of damaged leucocytes, and may cause Transfusion-Associated Adverse Reactions (TAARs) and transfusion-induced systemic inflammation. Although this is well-known, very little scientific research has investigated the clinical implications and actual adverse effects these abnormal cytokine levels in blood products from donors with underlying chronic inflammatory diseases have on vulnerable recipients, particularly critically-ill patients who are already prone to inflammation.