The effect of agitating buffy coats on platelet quality before soft spin.

BACKGROUND: Platelet plays a vital role in both physiological and pathological processes. However, the limited storage time of platelet in vitro poses an immense challenge for its applications because of the increased risk of bacterial contamination and platelet storage lesions. Agitation can inhibit lesions by facilitating continuous oxygenation of platelets and permitting excess carbon dioxide to be removed during storage. However, it is still not known whether agitating BCs gives a positive effect on platelet quality. OBJECTIVES: To evaluate the quality difference between platelet concentrates (PCs) from buffy coats (BCs) held rest and agitation. METHODS: Samples were withdrawn for cell count, blood gas analysis, free hemoglobin level, hypotonic shock response, maximum aggregation rate, activation marker expression (CD62P and CD42b) and coagulation function. RESULTS: We found the PCs prepared from the agitating BCs had fewer residual WBCs, exhibited a better gas exchange ability, slower metabolism (higher pH, higher content glucose, and lower lactic acid levels), better hypotonic shock response, and lower levels of CD62P. The TEG-PC assays showed no difference in coagulation function. CONCLUSION: Our findings showed that BC can be agitated overnight before a soft spin.

Are we missing reverse TRALI? - A real world experience from a tertiary care oncology centre in India.

Transfusion related acute lung injury (TRALI) is a rare but potentially fatal pulmonary complication of transfusion that presents as acute hypoxemia and non-cardiogenic pulmonary oedema, developing during or within six hours of transfusion. Majority of the cases reported are due to transfusion of plasma rich blood components containing antibodies to human leukocyte antigen (anti-HLA) or human neutrophil antigen (anti-HNA). Rarely, anti-HLA or anti-HNA in recipients against transfused donor leukocyte antigens, cause TRALI by a reverse mechanism. Herein, we report three cases of suspected TRALI following transfusions of buffy coat derived granulocytes and peripheral blood stem cells. Three patients with hematological malignancies developed pulmonary symptoms after transfusions of leukocyte rich blood components. All cases showed findings of bilateral pulmonary infiltrates at chest radiography and patients were managed accordingly; however, all three expired within seven days of transfusion due to progressive respiratory deterioration. The patients were transfusion dependent for a long time and had received multiple non-leukoreduced blood components in the past. Clinical findings in all three cases indicate the possibility of reverse TRALI. Although, patients' anti-HLA or anti-HNA antibodies concordance with donors' cognate antigens (HLA and HNA) was not confirmed; yet these three cases suggest that reverse pathogenesis of TRALI is not as infrequent as reported in the literature. However, reverse TRALI has not been confirmed as the presence and nature of antibodies in the transfused recipient were not investigated due to the non availability of immunodiagnostic tests in India.

Comparison of human platelet lysate alternatives using expired and freshly isolated platelet concentrates for adipose-derived stromal cell expansion.

Pooled human platelet lysate (pHPL) has been used to expand adipose-derived stromal cells (ASCs) and can be formulated using fresh or expired buffy coats (BCs) which are then resuspended in either plasma or an additive solution. Not much is known about the effects that expired products and additive solutions have on ASC expansion, and the need for quality control and release criteria has been expressed. This pilot study compared proliferation, cell size, morphology and immunophenotype of ASCs expanded in the different pHPL alternatives versus foetal bovine serum (FBS). Quality control criteria were assessed prior to and during the manufacture of the pHPL alternatives. ASCs were then expanded in 1%, 2.5%, 5% or 10% of the different pHPL alternatives or in 10% FBS. Cell size, morphology, cell number and immunophenotype were measured using microscopy and flow cytometry. The majority of the pHPL alternatives were within the recommended ranges for the quality control criteria. ASCs expanded in the pHPL alternatives were smaller in size, displayed a tighter spindle-shaped morphology, increased cell growth and had a similar immunophenotype (with the exception of CD34 and CD36) when compared to ASCs expanded in FBS. Here we report on the effects that expired BC products and additive solutions have on ASC expansion. When taken together, our findings indicate that all of the pHPL alternatives can be considered to be suitable replacements for FBS for ASC expansion, and that expired BC products can be used as an alternative to fresh BC products.

Classification of biosensor time series using dynamic time warping: applications in screening cancer cells with characteristic biomarkers.

The development of biosensors that produce time series data will facilitate improvements in biomedical diagnostics and in personalized medicine. The time series produced by these devices often contains characteristic features arising from biochemical interactions between the sample and the sensor. To use such characteristic features for determining sample class, similarity-based classifiers can be utilized. However, the construction of such classifiers is complicated by the variability in the time domains of such series that renders the traditional distance metrics such as Euclidean distance ineffective in distinguishing between biological variance and time domain variance. The dynamic time warping (DTW) algorithm is a sequence alignment algorithm that can be used to align two or more series to facilitate quantifying similarity. In this article, we evaluated the performance of DTW distance-based similarity classifiers for classifying time series that mimics electrical signals produced by nanotube biosensors. Simulation studies demonstrated the positive performance of such classifiers in discriminating between time series containing characteristic features that are obscured by noise in the intensity and time domains. We then applied a DTW distance-based k-nearest neighbors classifier to distinguish the presence/absence of mesenchymal biomarker in cancer cells in buffy coats in a blinded test. Using a train-test approach, we find that the classifier had high sensitivity (90.9%) and specificity (81.8%) in differentiating between EpCAM-positive MCF7 cells spiked in buffy coats and those in plain buffy coats.

The comparison among the three models of pooled buffy coats in preparing the platelet concentrate / 重庆医学

Objective To compare the quality and preservation effect among the three models of pooled buffy coats (PBC) in pre-paring the platelet concentrate (PC) .Methods 63 identical ABO blood donations were randomly and averagely divided into three groups :the immediate PBC group(n=21) ,the buffy coats(BC) group(n=21) and the whole blood(WB) group(n=21) .In the im-mediate PBC group ,both the separation of the BC and the preparation of the PC was finished in the first day after collecting the WB;in the BC group ,the separation of BC was executed in the first day after collecting the WB ,while the preparation of the PC was completed in the second day ;in the WB group ,both the separation of the BC and the preparation of the PC was implement in the second day after collecting the WB .All the prepared PC were storage at (22 ± 2) ℃ for seven days in the preservation solution (composed by 2/3 PAS-ⅢM and 1/3 plasma) .Then compare the platelet(PLT) counts ,the red blood cell(RBC) residual quanti-ties ,the aggregative function of PLT ,the positive expression rates of CD62p ,the capability of hypotonic shock response(HSR) ,the PH value and the bacterial growth among PCs prepared by the three models during the stored time .Results Compared the immedi-ate PBC group during the seven stored days ,the PLT counts of the BC and WB groups were more ,the aggregative function of PLT in the BC group was better and the capability of HSR in the WB group was stronger ,but the other indexs between the immediate PBC group and the BC or WB group were no significant difference(P>0 .05) .Conclusion Both an overnight holding of BC and WB at room temperature models of PBC to prepare the PC are safe ,reliable and convenient ,and they could be substitute for the immedi-ate PBC model to prepare the PC .

Preparation of leukoreduced platelet concentrates from pooled buffy coats in a mixture of solutions for medical use / 中国输血杂志

Objective To develop a method to produce leukoreduced platelet concentrates(LR-PCs) from pooled buffy coats in additive solution(a mixture of solutions for medical use).Methods LR-PCs were made from 6 pooled buffy coats(12 whole-blood units) and 220g additive solution,including 90% multiple electrolytes injection solution,8% ACD-A and 2% 50g/L NaHCO3 injection solution.After centrifugation,the PCs were leukoreduced with a filter and stored in a 600ml platelet storage bag.LR-PCs were prepared in a closed system.Results Routinely produced LR-PCs(n=30) contained(2.96?0.31)?1011 platelets with a volume of(270? 32)ml.The WBC and RBC count were(1.3?0.2)?106 and(5.8?1.1)?109 per unit,respectively.The CD62P expression was(22.5? 10.6)%.After 8-day storage,the in vitro quality of LR-PCs,including pH,hypotonic shock response(HSR) and CD62P expression were 7.14?0.04,(54.0?8.2)% and(45.7?13.8)%,respectively.Conclusion In terms of the in vitro quality of LR-PCs,the method of preparing LR-PCs from pooled buffy coats in mixing solutions is feasible.