Microarray kit analysis of cytokines in blood product units and segments

Abstract

BACKGROUND-Cytokine concentrations in transfused blood components are of interest for some clinical trials. It is not always possible to process samples of transfused components quickly after their administration. Additionally, it is not practical to sample material in an acceptable manner from many bags of components before transfusion, and after transfusion, the only representative remaining fluid of the component may be that in the "segment," as the bag may have been completely transfused. Multiplex array technology allows rapid simultaneous testing of multiple analytes in small volume samples. We used this technology to measure leukocyte cytokine levels in blood products to determine (1) whether concentrations in segments correlate with those in the main bag, and thus, whether segments could be used for estimation of the concentrations in the transfused component; and (2) whether concentrations after sample storage at 4C for 24 hrs do not differ from concentrations before storage, thus allowing for processing within 24 hrs, rather than immediately after transfusion.

Segments from red blood cell units should not be used for quality testing

“…One study demonstrated that unique segments can be used to give a close approximation of unit Hct; however, in this instance the segments were designed specifically to test this, unlike the segments used in our study that are primarily used for serologic testing and due to production methods may not be contiguous with the bag content. Another study showed no difference in cytokine levels from RBC units or their corresponding segments . However, the majority of studies have shown that there is little correlation between segments and their corresponding units in terms of hemolysis .…”

“…Another study showed no difference in cytokine levels from RBC units or their corresponding segments. 16 However, the majority of studies have shown that there is little correlation between segments and their corresponding units in terms of hemolysis. 4,5,7 Although visual assessment of segments is sometimes used to assess hemolysis in a unit and can be used as a criterion for discarding units at hospitals or blood banks, it has been shown that this can be misleading and that hemolysis in segments is a poor predictor of hemolysis in the units.…”

The effect of storage on ammonia, cytokine, and chemokine concentrations in feline whole blood

“…Instead of using entire units of blood, two to five 1 mL aliquots of blood were isolated in the collection tubing immediately following blood donation and complete mixing with the anticoagulant solution. These aliquots were stored at 4°C within the blood bank refrigerator, and were considered to be representative of the entire donor unit . At each of the weekly time points, the blood from each aliquot was centrifuged at 1,500 x g , and the plasma was collected.…”

Relationships between inflammatory cytokine and cortisol responses in firefighters exposed to simulated wildfire suppression work and sleep restriction

“…Values below the detectable range of the Milliplex Human MAP Cytokine immunoassay kit (IL‐4 = 18% of sample; IL‐6 = 0.9% of sample; IL‐1 β = 0.2% of sample; IL‐8 = 0.7% of sample; IL‐10 = 1.4% of sample; TNF‐ α = 0.2% of sample) were replaced with the minimal detectable concentration as advised in the protocol (Weiskopf et al. ; Liberati et al. ).…”

“…Prior to the analysis, cytokine values >2 standard deviations above (IL-4 = 5% of sample; IL-6 = 6% of sample; IL-1b = 6% of sample; IL-8 = 6% of sample; IL-10 = 5% of sample; TNF-a = 4% of sample) the mean were considered outliers and subsequently removed (Finnerty et al 2008;Nguyen et al 2010). Values below the detectable range of the Milliplex Human MAP Cytokine immunoassay kit (IL-4 = 18% of sample; IL-6 = 0.9% of sample; IL-1b = 0.2% of sample; IL-8 = 0.7% of sample; IL-10 = 1.4% of sample; TNFa = 0.2% of sample) were replaced with the minimal detectable concentration as advised in the protocol (Weiskopf et al 2009;Liberati et al 2013). With the exception of TNF-a (for which raw values achieved normality and homogeneity of variance), all cytokine, cortisol, and activity count measurements were adjusted using a natural log transformation to achieve normality, assessed using the Shapiro-Wilk test (P > 0.05).…”