Changing Strategies for the Detection of Bacteria in Platelet Components in Ireland: From Primary and Secondary Culture (2010-2020) to Large Volume Delayed Sampling (2020-2023).

Bacterial contamination of platelet components (PC) poses the greatest microbial risk to recipients, as bacteria can multiply over the course of PC storage at room temperature. Between 2010 and 2020, the Irish Blood Transfusion Service (IBTS) screened over 170,000 buffy coat-derived pooled (BCDP) and single-donor apheresis platelets (SDAPs) with the BACT/ALERT 3D microbial detection system (Biomerieux, L'Etoile, France), using a two-step screening protocol which incorporated primary and secondary cultures. Although the protocol was successful in averting septic transfusion reactions (STRs), testing large sample volumes at later time points was reported to improve detection of bacterial contamination. A modified large-volume delayed sampling (LVDS)-type protocol was adopted in 2020, which in the case of SDAP was applied to collections rather than individual splits (2020-2023, 44,642 PC screened). Rates of bacterial contamination for BCDP were 0.125% on Day-2, 0.043% on Day-4 vs. 0.191% in the post-LVDS period. SDAP contamination rates in the pre-LVDS period were 0.065% on Day-1, 0.017% on Day-4 vs. 0.072% in the post-LVDS period. Confirmed STRs were absent, and the interdiction rate for possibly contaminated SDAP was over 70%. In the post-LVDS period, BCDPs had a higher total positivity rate than SDAPs, 0.191% (1:525) versus 0.072% (1:1385), respectively, (chi-squared 12.124, 1 df, p = 0.0005). The majority of organisms detected were skin-flora-type, low pathogenicity organisms, including coagulase-negative staphylococci and Cutibacterium acnes, with little change in the frequency of clinically significant organisms identified over time. Both protocols prevented the issue of potentially harmful components contaminated (rarely) with a range of pathogenic bacteria, including Escherichia coli, Serratia marcesens, Staphylococcus aureus, and streptococci. Culture positivity of outdates post-LVDS whereby 100% of expired platelets are retested provides a residual risk estimate of 0.06% (95% CI 0.016-0.150). However, bacterial contamination rates in expired platelets did not demonstrate a statistically significant difference between the pre-LVDS 0.100% (CI 0.033-0.234) and post-LVDS 0.059% (0.016-0.150) periods (chi-squared = 0.651, 1 df, p = 0.42).

Microbiological environmental contamination in the blood supply chain: An international survey by the bacterial subgroup of the ISBT Transfusion-Transmitted Infectious Diseases Working Party.

BACKGROUND AND OBJECTIVES: Blood transfusion centres ensure the quality and safety of transfusable blood components. However, septic transfusion reactions involving environmental contaminants occur. An international survey issued by the ISBT Transfusion-Transmitted Infectious Diseases Working Party (ISBT-TTID-WP) Bacterial Subgroup aimed to collect information regarding microbiological environmental monitoring from transfusion services. MATERIALS AND METHODS: A Form survey (English and Spanish) with 35 questions was sent to ISBT-TTID-WP members. The survey had four sections: (1) respondent personal information, (2) cleaning/disinfection practices during blood component manufacturing, (3) cleaning/disinfection practices during blood component storage and (4) blood component storage bag integrity. Respondents completed the survey electronically, and data were comparatively analysed using Microsoft Excel. RESULTS: There were 49 responses from 20 countries. Five of 49 sites manufacture blood components in a cleanroom, and most use personal protective equipment, although the type varied between sites. Approximately 40% of sites perform environmental monitoring during blood component production, with seven sites providing details about frequency and methods. Most (~94%) centres have procedures for cleaning/disinfection of processing and storage facilities with varying responses regarding areas, frequency and methods. Inconsistency was reported regarding the orientation of platelet component incubation (portrait vs. landscape). Over 93% of sites assess storage bag integrity and report damage to manufacturers, and 49% of centres report septic transfusion reactions potentially linked to damaged storage containers. CONCLUSION: Data from this survey highlight the need for consensual guidelines for transfusion services regarding cleaning and disinfection practices. Environmental monitoring could be adopted to minimize the risk of blood component contamination for transfusion patient safety.

Recommendations for in vitro evaluation of blood components collected, prepared and stored in non-DEHP medical devices.

BACKGROUND AND OBJECTIVES: DEHP, di(2-ethylhexyl) phthalate, is the most common member of the class of ortho-phthalates, which are used as plasticizers. The Medical Device Regulation has restricted the use of phthalates in medical devices. Also DEHP has been added to the Annex XIV of REACH, "Registration, Evaluation, Authorisation and Restriction of Chemicals" due to its endocrine disrupting properties to the environment. As such, the sunset date for commercialisation of DEHP-containing blood bags is May 27th 2025. There are major concerns in meeting this deadline as these systems have not yet been fully validated and/or CE-marked. Also, since DEHP is known to affect red cell quality during storage, it is imperative to transit to non-DEHP without affecting blood product quality. Here, EBA members aim to establish common grounds on the evaluation and assessment of blood components collected, prepared and stored in non-DEHP devices. MATERIALS AND METHODS: Based on data as well as the input of relevant stakeholders a rationale for the validation of each component was composed. RESULTS: The red cell components will require the most extensive validation as their quality is directly affected by the absence of DEHP, as opposed to platelet and plasma components. CONCLUSION: Studies in the scope of evaluating the quality of blood products obtained with non-DEHP devices, under the condition that they are carried out according to these recommendations, could be used by all members of the EBA to serve as scientific support in the authorization process specific to their jurisdiction or for their internal validation use.

Study on platelet components production in 19 provincial blood centers in China before and during the COVID-19 epidemic / 中国输血杂志

【Objective】 To study the changes of platelet components(PC), apheresis platelets (AP) and pooled platelet concentrates (PPC) production of 19 provincial blood centers before and during the COVID-19 epidemic. 【Methods】 The data related to the collection of AP and the preparation of PPC from 2016 to 2021 of 19 provincial blood centers was collected. The production of PC, AP and PPC during the four years before the epidemic (i.e. 2016-2019) and during the COVID-19 epidemic (i.e. 2020 and 2021) were calculated respectively, and the change of production was analyzed. 【Results】 The total production of PC in 19 blood centers steadily increased from 2016 to 2019, with a decrease of 4.16% in 2020 and an increase of 15.60% in 2021, exceeding the output before the COVID-19 epidemic. In 2020, the production of PC of 42.11% (8/19) blood centers decreased compared with 2019, while 94.74% (18/19) in 2021 increased compared with 2020. The changes of AP output was basically consistent with the trend of PC. The total production of PPC in 2017 and 2018 both doubled compared to the previous year, while decreased by 67.98% in 2019, increased by 30.38% in 2020 and decreased by 27.08% in 2021. 【Conclusion】 The total production of PC kept increasing steadily between 2016 and 2019, but decreased in 2020 under the COVID-19 epidemic, with some blood centers being significantly affected. In 2021, with the strong support from government and various measures by blood centers, the total production of PC increased.

Pathogen inactivation treatment of triple-dose apheresis platelets with amotosalen and ultraviolet a light.

BACKGROUND: A triple storage (TS) set allows for pathogen inactivation (PI) treatment of triple-dose apheresis platelet products with amotosalen + UVA. We evaluated the quality and metabolic parameters of platelet concentrates (PCs) pathogen inactivated and stored for 7 days. MATERIALS AND METHODS: Twelve triple-dose products collected with two different apheresis platforms were treated with amotosalen+UVA. Products were split into three single-dose units. Testing was made pretreatment, after splitting, at days 5 and 7 of storage. RESULTS: Single-dose PI PCs had a mean platelet content of 2.89 ± 0.35 x 1011 . From baseline to day 7, pH remained stable (7.1 ± 0.1 vs. 7.0 ± 0.1), pO2 increased (11.3 ± 2.4 vs. 18.3 ± 3.5 kPa) as did LDH (201 ± 119 vs. 324 ± 203 U/L) and lactate (3.6 ± 1.7 vs. 12.1 ± 1.5 mmol/L) (all p < 0.01); pCO2 decreased (4.1 ± 0.8 vs. 1.5 ± 0.7 mmHg; p < 0.01) and so did bicarbonate (6.6 ± 1.1 vs. 2.5 ± 1.4 mmol/L), glucose (5.6 ± 1.2 vs. 0.4 ± 0.4 mmol/L) and ATP (3.4 ± 0.9 vs. 2.5 ± 1.4 nmol/108 platelets) (all p < 0.05). CONCLUSION: Triple-dose PCs processed with the TS sets fulfilled the quality requirements and displayed metabolic changes of expected extent during 7-day storage.

Current status of rapid bacterial detection methods for platelet components: A 20-year review by the ISBT Transfusion-Transmitted Infectious Diseases Working Party Subgroup on Bacteria.

BACKGROUND AND OBJECTIVES: Bacterial contamination of platelet components (PCs) poses a safety challenge for transfusion patients. Despite mitigation interventions, the residual risk of transfusion-transmitted bacterial infections remains predominant. PC safety can be improved either by pathogen reduction or by implementation of bacterial detection methods. Detection methodologies include culture methods and rapid detection methods. The current review focuses on currently available rapid detection methods. MATERIALS AND METHODS: We reviewed published manuscripts since 2000 on rapid bacterial detection methods used for PC screening with result determination within 4 h. Methods meeting this criterion included Verax PGDprime, BacTx and nucleic amplification testing. The analytical and diagnostic sensitivity and specificity of these systems were assessed. RESULTS: The analytical sensitivity between the different detection methods ranged between 50 and 100,000 CFU/ml. The sample volume used by these testing systems varies between 0.5 and 1.0 ml of PCs. A delay of at least 48 h before sampling enhances detectability. All rapid detection methods generate results in a timely manner, allowing testing to be performed before transfusion with optimal sensitivity. CONCLUSION: Rapid detection methods improve PC safety regarding bacterial contamination. The assays are optimal for rapidly growing bacteria, which are more likely to cause septic transfusion reactions in patients. Because of the reduced diagnostic sensitivity, the sample collection should be late in shelf-life and ideally just before transfusion. The major benefit of these methods is that the test result can be obtained before releasing PCs for transfusion or to be used in combination with other screening methods applied early during PC storage.

Residual risks of bacterial contamination for pathogen-reduced platelet components.

Platelet components are commonly transfused to patients for a variety of indications, including patients with low platelet counts or patients with platelet dysfunction who are bleeding or at high risk of bleeding. Although the risk of pathogen contamination of platelet components has declined significantly over the last 40 years, it remains a concern for the patients, for blood banks and for physicians. Pathogen inactivation (PI) technologies have been developed to mitigate this risk. This review focuses on the residual risks of transfusion-transmitted bacterial infections by platelet transfusion after PI. We describe and assess the relationship between the bacterial load and the timing and capacity of reduction of the different PI technologies, as well as the risks that could represent spore-forming microorganisms and the possible introduction of microorganisms after PI.

A randomized study of a best practice alert for platelet transfusions.

BACKGROUND AND OBJECTIVES: Inappropriate platelet transfusions represent an opportunity for improvements in patient care. Use of a best practice alert (BPA) as clinical decision support (CDS) for red cell transfusions has successfully reduced unnecessary red blood cell (RBC) transfusions in prior studies. We studied the impact of a platelet transfusion BPA with visibility randomized by patient chart. MATERIALS AND METHODS: A BPA was built to introduce CDS at the time of platelet ordering in the electronic health record. Alert visibility was randomized at the patient encounter level. BPA eligible platelet transfusions for patients with both visible and non-visible alerts were recorded along with reasons given for override of the BPA. Focused interviews were performed with providers who interacted with the BPA to assess its impact on their decision making. RESULTS: Over a 9-month study period, 446 patient charts were randomized. The visible alert group used 25.3% fewer BPA eligible platelets. Mean monthly usage of platelets eligible for BPA display was 65.7 for the control group and 49.1 for the visible alert group (p = 0.07). BPA-eligible platelets used per inpatient day at risk per month were not significantly different between groups (2.4 vs. 2.1, p = 0.53). CONCLUSION: It is feasible to study CDS via chart-based randomization. A platelet BPA reduced total platelets used over the study period and may have resulted in $151,069 in yearly savings, although there were no differences when adjusted for inpatient days at risk. During interviews, providers offered additional workflow insights allowing further improvement of CDS for platelet transfusions.

[Study on the intervention of platelet biological activity by ultrasound].

Platelets are non-nucleated blood effector cells, which plays an important role in coagulation, hemostasis, and thrombosis. However, platelets are extremely susceptible to activation by external stimuli, which in turn damages the platelet's natural biological activity and affects its biological function. Platelet biological activity has become a hotspot in the field of vascular diseases. In this study, ultrasound parameters (ultrasound intensity and duration time) were used to intervene in the biological activity of platelets. The response of platelets to ultrasound energy was explored from the aspects of platelet morphology, aggregation ability and particle release (the expression of P-selectin and the number of particles). The results showed that the ultrasound intensity of 0.25 W/cm 2 (1 MHz, 60 s) had no effect on the morphology, aggregation ability and particle release of platelets. When the ultrasonic intensity was increased to greater than 0.25 W/cm 2, the generation of platelet pseudopods, morphological changes, increase of particle release, as well as effect on aggregation were observed. When the ultrasound duration time was 60 s (1 MHz, 0.25 W/cm 2), it had no effect on the biological activity of platelets. However, when the ultrasound time was greater than 60 s, the morphology, aggregation ability and microparticles release would been induced with no effect on the secretion of CD62P and total protein components. Therefore, when the ultrasound parameters were 1 MHz and 0.25 W/cm 2 with 60 s duration time, the ultrasound energy had no effect on the biological activity of platelets. The results in this study are of great significant for ultrasound energy intervention for the treatment of platelet-related diseases.

The incremental benefit of anaerobic culture for controlling bacterial risk in platelets: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: Septic transfusion reactions are a principal cause of transfusion-related mortality. The frequency of detectable bacterial contamination is greater in platelets compared to other blood components because platelets are stored at room temperature. Most strategies outlined in the September 2019 FDA guidance require both aerobic culture (AC) and anaerobic culture (AnC) testing. We performed a systematic review and meta-analysis in an effort to provide the best available estimate of the effectiveness of AnC. MATERIALS AND METHODS: Our analysis was performed according to published guidelines. Broad and context-specific meta-analyses of bacterial detection rates in platelets by AnC were performed to assess the practical effectiveness of AnC as a risk control measure. RESULTS: Seven studies with a total of 1 767 014 tested platelet components were included for analysis. With exclusion of positives due to Cutibacterium/Propionibacterium species and redundancy due to AC results, AnC detected 0·06 contamination events per thousand (EPT) components tested, twofold lower than the AC (0·12 EPT). CONCLUSION: Excluding Cutibacterium/Propionibacterium species, AnC detects occasional bacterial contamination events that are not detected by AC (~1 in 17 000 platelet components).

Study on the intervention of platelet biological activity by ultrasound / 生物医学工程学杂志

Platelets are non-nucleated blood effector cells, which plays an important role in coagulation, hemostasis, and thrombosis. However, platelets are extremely susceptible to activation by external stimuli, which in turn damages the platelet's natural biological activity and affects its biological function. Platelet biological activity has become a hotspot in the field of vascular diseases. In this study, ultrasound parameters (ultrasound intensity and duration time) were used to intervene in the biological activity of platelets. The response of platelets to ultrasound energy was explored from the aspects of platelet morphology, aggregation ability and particle release (the expression of P-selectin and the number of particles). The results showed that the ultrasound intensity of 0.25 W/cm

Skin flora and bacterial contamination of diversion pouch and recovered platelet components in Moroccan blood donors.

OBJECTIVE: The objective of this study was to evaluate bacterial reduction procedures used during whole-blood donations in Morocco. BACKGROUND: Bacterial contamination still poses serious challenges to blood safety, especially in countries with limited resources. METHODS: In the first part of this study, we analysed 233 swab samples taken from blood donors' antecubital fossa. After donation, a second batch of samples was analysed from the diversion pouches of corresponding donors. In addition, we searched for the prevalence of bacterial contamination in 568 randomly chosen platelet components at their expiration date in order to control for the entire blood unit preparation process. RESULTS: The most frequently found bacterial species at the antecubital fossa of healthy blood donors were coagulase-negative Staphylococcus, aerophilic Corynebacterium, Staphylococcus aureus, Bacillus sp. and Micrococcus sp. After donation, 5.15% of the diversion pouches were contaminated with bacterial species, the most notable being Bacillus sp., aerophilic Corynebacterium, coagulase-negative Staphylococcus, Staphylococcus aureus and Pseudomonas aeruginosa. Of 568 platelet components, 18 were contaminated with three bacterial species: Bacillus sp., coagulase-negative Staphylococcus and Staphylococcus aureus. CONCLUSION: All three bacterial species found in platelet components were detected on the skin of blood donors. Serious measures need to be taken and enforced to ensure blood safety.

Immunological Features in the Process of Blood Platelet-Induced Alloimmunisation, with a Focus on Platelet Component Transfusion.

Alloimmunisation to platelet antigens is not uncommon; a large number of females, having had pregnancies, developed antibodies to Human Leukocyte Antigen (HLA) moieties harboured on their foetuses' cells (inherited from the father(s)) that may conflict with further pregnancies and transfused Platelet Components occasionally. This is possible since platelets constitutionally express HLA class I molecules (though in copy numbers that consistently differ among individuals). Platelets also express HPA moieties that are variants of naturally expressed adhesion and aggregation molecules; HPA differences between mothers and foetuses and between donors and recipients explain alloimmune conflicts and consequences. Lastly, platelets express ABO blood group antigens, which are rarely immunising, however transfusion mismatches in ABO groups seem to be related to immunisation in other blood and tissue groups. Transfusion also brings residual leukocytes that may also immunise through their copious copy numbers of HLA class I (rarely class II on activated T lymphocytes, B cells, and dendritic cells). In addition, residual red blood cells in platelet concentrates may induce anti-red blood cell allo-antibodies. This short review aims to present the main mechanisms that are commonly reported in alloimmunisation. It also critically endeavours to examine paths to either dampen alloimmunisation occurrences or to prevent them.

In vitro evaluation of pathogen inactivated platelet quality: An 8 year experience of routine use in Galicia, Spain.

BACKGROUND: Platelet concentrates (PCs) treated by the pathogen inactivation technology (PI) using amotosalen and UVA illumination (PI-PCs) can be manufactured in additive solutions (PAS-III and PAS-IIIM) or in 100% Plasma. Quality control (QC) is an integral part of the production. We capitalized on our ongoing QC program to capture 8 years-worth of data on parameters related to the quality of 116,214 PI-PCs produced under different manufacturing methods. MATERIALS AND METHODS: Selected in vitro parameters of metabolism, activation, and storage were analyzed for the different manufacturing periods to compare PI-PCs versus conventional PCs (C-PCs) resuspended in different PAS. RESULTS AND DISCUSSION: All BC-PCs met quality standards for pH and dose and residual leucocytes. As expected, storage time correlated with increased lactate, LDH, Annexin V, CD62, sCD40 L levels and decreased glucose and pH. With PAS-IIIM, higher levels of glucose were observed toward the end of shelf life (p < 0.0001) with lower platelet activation markers Annexin V (p = 0.038) and CD62 (p = 0.0006). Following PI implementation, a low expire rate of <0.5% was observed. While a 2.3% mean increase in the production of PCs occurred from 2011 to 2015, the distribution of red blood cell concentrates dropped by 4.4%. A mean incidence of 0.14% for transfusion-related adverse reaction was observed while PI-PCs were distributed, similar to the one observed with C-PCs. Overall, PI-PCs prepared in additive solutions consistently met quality standards. Those prepared in PAS-IIIM appeared to have better retention of in vitro characteristics compared to PAS-III though all demonstrated functionality and clinical effectiveness.

Bacterial contamination of platelet components not detected by BacT/ALERT®.

OBJECTIVES: To investigate the possible causes for false negative results in BacT/ALERT® 3D Signature System despite bacterial contamination of platelet units. BACKGROUND: The Northern Ireland Blood Transfusion Service (NIBTS) routinely extends platelet component shelf life to 7 days. Components are sampled and screened for bacterial contamination using an automated microbial detection system, the BacT/ALERT® 3D Signature System. We report on three platelet components with confirmed bacterial contamination, which represent false negative BacT/ALERT® results and near-miss serious adverse events. METHODS: NIBTS protocols for risk reduction of bacterial contamination of platelet components are described. The methodology for bacterial detection using BacT/ALERT® is outlined. Laboratory tests, relevant patient details and relevant follow-up information are analysed. RESULTS: In all three cases, Staphylococcus aureus was isolated from the platelet residue and confirmed on terminal sub-culture using BacT/ALERT® . In two cases, S. aureus with similar genetic makeup was isolated from the donors. CONCLUSION: Risk reduction measures for bacterial contamination of platelet components are not always effective. Automated bacterial culture detection does not eliminate the risk of bacterial contamination. Visual inspection of platelet components prior to release, issue and administration remains an important last line of defence.

Experiences with semi-routine production of riboflavin and UV-B pathogen-inactivated platelet concentrates in three blood centres.

BACKGROUND: For a clinical platelet (PLT) transfusion trial conducted in three countries, the production of PLT concentrates (PCs) that were pathogen inactivated with the Mirasol technology was set up and validated. While the Mirasol procedure is applied to an established PLT product, the PLT processing procedure still had to be modified to ensure a treated PC was of sufficient quality. Further, the effect of simulated transport conditions and the effect of ambient light on Mirasol-treated PCs was determined. STUDY DESIGN AND METHODS: Platelet concentrates in plasma were made from pooled buffy coats followed by Mirasol treatment. To mimic transport conditions, units were left unagitated for 6 h at room temperature. To mimic ambient light exposure, units were held unagitated for 4 h in direct fluorescent tube light. RESULTS: Measures had to be taken to allow 7-day storage of treated concentrates. In one site, PCs made from five buffy coats with >450 × 109 PLTs were removed from inventory. Another site went from five to four buffy coats per pool. Interruption of agitation for 6 h on day 3 did not induce meaningful changes in in vitro measures, even when stored up to 7 days. Exposure to ambient light for 4 h, either on day 3 or 6, had no effect on in vitro measures. CONCLUSION: The Mirasol pathogen inactivation process can be implemented in routine, but changes to current PLT processing methods might be needed. Transport conditions and 4-h-long ambient light exposure have no negative effect on the in vitro quality of Mirasol-treated PCs.

Platelet responses to agonists in a cohort of highly characterised platelet donors are consistent over time.

BACKGROUND AND OBJECTIVES: Platelet function shows significant inheritance that is at least partially genetically controlled. There is also evidence that the platelet response is stable over time, but there are few studies that have assessed consistency of platelet function over months and years. We aimed to measure platelet function in platelet donors over time in individuals selected from a cohort of 956 donors whose platelet function had been previously characterised. MATERIALS AND METHODS: Platelet function was assessed by flow cytometry, measuring fibrinogen binding and P-selectin expression after stimulation with either cross-linked collagen-related peptide or adenosine 5'-diphosphate. Eighty-nine donors from the Cambridge Platelet Function Cohort whose platelet responses were initially within the lower or upper decile of reactivity were retested between 4 months and five and a half years later. RESULTS: There was moderate-to-high correlation between the initial and repeat platelet function results for all assays (P ≤ 0·007, r2 0·2961-0·7625); furthermore, the range of results observed in the initial low and high responder groups remained significantly different at the time of the second test (P ≤ 0·0005). CONCLUSION: Platelet function remains consistent over time. This implies that this potential influence on quality of donated platelet concentrates will remain essentially constant for a given donor.

Amelioration of lesions associated with 24-hour suboptimal platelet storage at 16 °C by a p38MAPK inhibitor, VX-702.

BACKGROUND AND OBJECTIVES: Previous studies with p38MAPK inhibitors at room temperature demonstrated that they improve a large number of platelet storage parameters, but cannot substantially inhibit p38MAPK activation nor protect against widespread decrements in platelet quality parameters during 4 °C storage. In this study, platelet quality parameters and inhibition of p38MAPK by VX-702 were studied after incubation of platelets at 16 °C without agitation, suboptimal storage conditions which produce moderate platelet decrements. MATERIALS AND METHODS: Trima apheresis units were collected and aliquoted into three 60-ml CLX storage bags: (i) a control aliquot which was held at 20-24 °C with constant agitation; (ii) a test aliquot which was held at 20-24 °C with agitation until Day 2, when it was reincubated at 16 ± 1 °C for 24 ± 0·5 h without agitation and then returned 20-24 °C with agitation; (iii) a test aliquot containing 1 µm VX-702 stored in an identical fashion as aliquot 2. Aliquots were tested for an array of platelet storage parameters and p38MAPK activation on Days 1, 4 and 7. RESULTS: Many platelet storage parameters and p38MAPK activation were adversely affected by 24-h incubation at 16 °C without agitation. With the exception of ESC, addition of VX-702 prevented p38MAPK activation and the decrements in most observed parameters. CONCLUSION: Unlike 4 °C storage, VX-702 prevents activation of p38MAPK and decrements in many platelet storage parameters after exposure to 16 °C without agitation for 24 h.

Component pathogen inactivation: a critical review.

BACKGROUND AND OBJECTIVES: Pathogen inactivation (PI)-treated plasma and platelets are increasingly becoming the products of choice, where licensed. This review summarizes the clinical evidence available for licensed component PI technologies and red cell PI under development. MATERIALS AND METHODS: Available literature on licensed technologies was reviewed. RESULTS: For the plasma and platelets technologies available, evidence for the inactivation of most pathogens is good, except for certain nonenveloped viruses. Clinical trials and haemovigilance programmes suggest the observed loss of potency is of little clinical significance, with some technology-specific exceptions. Concerns over adverse toxicological effects or neoantigen formation have not been confirmed for currently licensed products. CONCLUSION: While platelet PI has been adopted to reduce bacterial contamination, the ability of PI methods to replace testing for emerging bloodborne infections, or as a substitute for selective pathogen testing, gamma-irradiation or even leucodepletion, make adoption of PI for components increasingly attractive.