Types Of Platelet Concentrates Research Articles

Are Buffy-coat Pooled Platelet Concentrates an Effective Alternative to Apheresis Platelet Concentrates? An In vitro Analysis at a Tertiary Care Center in Northern India.

There is a need for platelet products to have the best quality. Apheresis platelet concentrates (PCs) obtained from single-donors PCs (SD-PCs) are considered best but have issues such as feasibility and cost. Buffy-coat pooled PCs (BCP-PCs) are considered an alternative to SD-PCs. This study compares BCP-PCs and SD-PCs for in vitro quality parameters and their changes during storage. Fifteen units of BCP-PCs and 15 units of SD-PCs were prepared. In this study, a pool of five buffy coats was prepared. Fifteen units of BCP-PCs were analyzed on day 1 and day 5 of storage, while 15 SD-PCs were analyzed on day 1 while ten units on day 5. The parameters analyzed were volume, hematological parameters, pH, swirling, and sterility. The mean platelets count of SD-PCs was found to be significantly higher as compared to BCP-PCs. White blood cells (WBCs) contamination was significantly lower in BCP-PCs as compared to SD-PCs. The mean pH and mean platelet volume of SD-PCs were significantly lower than BCP-PCs. During storage, the mean platelets count of BCP-PCs was decreased significantly while that of SD-PCs nonsignificantly. The mean WBCs count and pH decreased in both BCP-PCs and SD-PCs significantly. All units in both types of PCs were sterile. Platelet yield was significantly better in SD-PCs, while mean WBCs contamination was significantly lower in BCP-PCs. BCP-PCs may be preferred in place of SD-PCs in case of nonavailability of apheresis, difficulty in finding a willing donor, or when the cost is of consideration.

Comparative Evaluation of Open Flap Debridement Therapy with Two Different Types of Platelet Concentrates, T-PRF and L-PRF as Adjuncts- A Systematic Review

Conventional Periodontal therapy such as scaling and root planing and open flap debridement aims to halt the inflammation process and promotes repair of disease-related defects. Current regenerative procedures offers a limited potential toward attaining a complete periodontal restoration and none is considered a gold standard in the treatment of intrabony defects. This study was done to compare the efficiency of Titanium-Platelet Rich Fibrin and Leukocyte-Platelet Rich Fibrin as adjuncts to Open Flap Debridement therapy to treat intra-bony periodontal defects. A search was conducted through PubMed and various other databases such as Cochrane, Google Scholar and EBSCO Host , under the key words, OFD , T-PRF,L-PRF, Clinical Outcomes, Comparison and Randomised Contolled Trials. Six relevant articles were selected for analysis. Compared to non-platelet concentrates, L-PRFproves to be the better adjunct to open flap debridement therapy. When compared to T-PRF, however, L-PRF has comparatively inferior properties of bone defect resolution and fill.We can conclude that T-PRF has better properties, greater bone defect fill and defect resolution as compared to L-PRF.

Regenerative Effect of Platelet Concentrates in Oral and Craniofacial Regeneration.

Platelet concentrates (PCs) are biological autologous products derived from the patient's whole blood and consist mainly of supraphysiologic concentration of platelets and growth factors (GFs). These GFs have anti-inflammatory and healing enhancing properties. Overall, PCs seem to enhance bone and soft tissue healing in alveolar ridge augmentation, periodontal surgery, socket preservation, implant surgery, endodontic regeneration, sinus augmentation, bisphosphonate related osteonecrosis of the jaw (BRONJ), osteoradionecrosis, closure of oroantral communication (OAC), and oral ulcers. On the other hand, no effect was reported for gingival recession and guided tissue regeneration (GTR) procedures. Also, PCs could reduce pain and inflammatory complications in temporomandibular disorders (TMDs), oral ulcers, and extraction sockets. However, these effects have been clinically inconsistent across the literature. Differences in study designs and types of PCs used with variable concentration of platelets, GFs, and leucocytes, as well as different application forms and techniques could explain these contradictory results. This study aims to review the clinical applications of PCs in oral and craniofacial tissue regeneration and the role of their molecular components in tissue healing.

Hypersensitivity transfusion reactions to platelet concentrate: a retrospective analysis of the French hemovigilance network.

Among labile blood products, platelet concentrates (PCs) are the leading cause of hypersensitivity transfusion reactions (HTRs). These reactions often lead to interruption of PC transfusion and can result in a prolonged transfusion process leading to significant morbidity and use of premedication and close monitoring for patients with a history of allergic transfusion reactions. The French hemovigilance database is one of the largest standardized databases providing information on HTRs following administration of labile blood products. In this study, we analyzed this database to assess the relative risk of HTR for each type of PC. HTRs following PC transfusion were retrospectively extracted from the e-Fit Hemovigilance database of the French National Agency for Medicines and Health Products Safety (ANSM). Frequencies were calculated using the number of specific PCs transfused. Between 2008 and 2014, the overall estimated incidence of HTRs following PC administration was calculated at 232 HTRs per 100,000 PCs transfused. The rate of HTRs was significantly higher with apheresis PC (337/100,000) than with buffy-coat PC (94/100,000). Platelets in additive solutions (PAS) were associated with a significantly lower frequency of HTRs when compared with PCs in native plasma. Amotosalen/UVA- PCs (APCs and BCPCs) which are always in PAS in France, exhibited the lowest frequency of HTRs when compared with their corresponding PCs in native plasma or in PAS (p < 10-7 in all comparisons). Our results showed that the type of PC and its processing may have an impact on the risk of HTR.

Microparticle and mitochondrial release during extended storage of different types of platelet concentrates

On activation, platelets release vesicles called microparticles (MPs). MPs are heterogeneous with regard to the presence or absence of mitochondria. We quantified MPs in platelet concentrates (PCs) taking their mitochondrial content into account. Platelet-rich plasma (PRP), buffy coat (BC) and apheresis (AP) PCs were tested through 7 days of storage. A combination of flow cytometry and spanning-tree progression analysis of density-normalized events (SPADE) was used to determine MP and mitochondrial release during storage. All the PC biochemical parameters complied with transfusion standards at all times. Platelet activation markers increased during storage and were higher for PRP than other types of PCs. Concentrations of MPs and extracellular mitochondria interpreted by SPADE algorithm were significantly higher in PRP than other in PCs and were stable throughout storage. The mode of preparation, rather than storage duration, impacts the release of MPs and mitochondria in PCs.

Italian daily platelet transfusion practice for haematological patients undergoing high dose chemotherapy with or without stem cell transplantation: a survey by the GIMEMA Haemostasis and Thrombosis Working Party.

Following high-dose chemotherapy/bone marrow transplantation, patients are routinely, prophylactically transfused with platelet concentrates (PC) if they have a platelet count ≤10×109/L or higher in the presence of risk factors for bleeding. However, whether such transfusions are necessary in clinically stable patients with no bleeding, or whether a therapeutic transfusion strategy could be sufficient and safe, is still debated. The GIMEMA Haemostasis and Thrombosis Working Party sent a questionnaire to Italian haematology departments to survey several aspects of daily platelet transfusion practice, such as the cut-off platelet count for transfusion, the evaluation of refractoriness and the type of PC administered. The questionnaire was answered by 18 out of 31 centres (58%). A total of 23,162 PC were transfused in 2,396 patients in 2013. The vast majority of centres (95%) transfused PC according to Italian and international guidelines; only a few transfused always at platelet counts ≤20×109/L. The broad agreement on platelet count cut-off for transfusion (≤10×109/L) was not confirmed when the World Health Organization (WHO) bleeding score was considered: only a third of centres (33%) used transfusions as recommended when the bleeding grade was ≥2. Platelet refractoriness was poorly monitored and most centres (89%) evaluated, mostly empirically (67%), response to transfusion only 24 hours later. Thirty percent of centres transfused platelets in asymptomatic refractory patients. Although most Italian haematology departments transfuse PC according to Italian and international guidelines, our survey shows that in routine daily practice physicians do not comply closely with the WHO recommendations on platelet transfusions and monitoring platelet refractoriness. This causes excessive platelet transfusions, with a resulting increase of costs and waste of public health resources.

The Effect of Variation in Donor Platelet Function on Transfusion Outcome: A Semi-Randomised, Double Blind, Controlled Trial (PROmPT)

Genetic variation is known to account for up to 70% of the wide variation in platelet function observed in healthy individuals. We have shown that platelet concentrates (PC) that are highly activated when collected by apheresis are produced from donors whose platelets are highly responsive to adenosine diphosphate (ADP) and collagen related peptide (CRP-XL) in vitro(high responder donors) with activation being measured by P-selectin expression and fibrinogen binding. The effect of this variation in donors on the outcome from platelet transfusion is unknown.The aim of the PROmPT trial (Platelet Responsiveness and Outcome from Platelet Transfusion, ISRCTN 56366401) was to test the hypothesis that PC following transfusion from high responder donors are cleared more rapidly from the circulation than PC from low responder donors.MethodWe established a cohort of 1,000 blood donors phenotyped for responsiveness to CRP (0.1-0.5 µg/mL) or ADP (10-7M) by flow cytometry. A sub-set of these individuals (26 high and 19 low responder donors) who reproducibly had global responses, i.e. not outliers for just one agonist, in the top and bottom 10% of the cohort were selected to supply apheresis platelets collected on the Terumo Trima system for the trial.The trial was designed as a parallel group, semi-randomised double-blinded trial in stable haematology patients who required prophylactic platelet transfusions. Based on 80% power, a 5% significance level, and a presumed 10% dropout, 100 patients (with the aim of 50 receiving a unit from high responders and 50 from low responders) were required to detect a mean difference of 7x109/L in the primary endpoint of the 1 hour (10-90 min) count increment (CI) between the high and low responder PC.Patients were randomised to receive a single PC from either a high or low responder donor when both were available. If only one type of PC was available then patients received that PC. Patients with factors known to affect platelet CI were excluded. In addition, 30 patients acted as controls, receiving non-trial PC from random donors. PCs were ABO and Rh compatible. Patients were followed up for 5 days or until their next platelet transfusion.Secondary outcomes included an assessment of bleeding score (modified WHO score) both by the patient and the clinician, 24 hour (12-36 hours) CI, as well as time to next platelet transfusion, and red cell transfusion requirements. CIs were adjusted for confounding factors that affect platelet increments, these were age and dose of PC, and body surface area.ResultsBaseline characteristics of patients were adequately balanced between groups. Fifty one patients received a PC from low responder donors, and 49 from high responder donors (47 of which were randomised and 53 non-randomised) and 30 patients received non-trial units (2 non trial transfusions were excluded from final analysis).There was no significant difference in the adjusted 1 hour CI, in patients receiving platelets from high or low responder donors (high response 21.04 versus low response 23.34x109/L; difference 2.30, 95%CI -1.09 to 5.69, p = 0.18) or the 24 hour platelet CI (high response 12.9 versus low response 14.31x109/L; difference 1.41, 95% CI -1.96 to 4.78, p = 0.41).There were no significant differences in all other secondary outcomes between patients receiving PC from high or low responder donors, including maximum bleeding scores (odds ratio 0.78, 95%confidence interval 0.29 to 2.16, p=0.64) and bleeding rates (number of days with Grade 2-4 bleed) (rate ratio was 0.70, 95% confidence interval 0.16 to 2.97, p = 0.63).In addition, there was no significant difference in 1 hour CI between patients receiving non-trial units and those from high (p = 0.28) or low responders (p = 0.95) or in any secondary outcomes.ConclusionsResults from this trial suggest that in a setting of prophylactic transfusion, the platelet responsiveness of the donor does not affect platelet count increments, bleeding scores, inter-transfusion interval or red cell usage in recipients. Further studies will be required to determine whether PC derived from high responders may be more efficacious in patients who are actively bleeding at the time of transfusion. DisclosuresNo relevant conflicts of interest to declare.

Does it matter which platelet‐rich plasma we use?

SummarySeveral commercial devices are available to the equine practitioner for preparation of platelet‐rich plasma (PRP). PRP is a ‘catch all’ term for a multitude of platelet concentrates (PC) with different biological components and properties. Case reports often fail to cite the exact type of PC used. A critical analysis of the available evidence on the clinical significance of differences between platelet concentrates is presented in an attempt to determine if one commercially available product is superior to the others.

The quality of platelet concentrates produced by COBE Spectra and Trima Accel cell separators during storage for 7 days as assessed by in vitro methods

The quality of platelet (PLT) concentrates (PCs) can be evaluated with various in vitro methods. A new technique, free oscillation rheometry (FOR), can be used to monitor coagulation properties of PCs and gives information on clotting time and coagulum elasticity. This study compared the quality of apheresis PCs produced by the COBE Spectra and Trima Accel cell separators (both Gambro BCT) during storage for 7 days with in vitro tests including FOR. Apheresis PCs were collected with the COBE Spectra (n = 10) and Trima Accel (n = 10) cell separators. Swirling, blood gases, and metabolic variables were analyzed on Day 0. Samples taken on Days 1, 5, and 7 were also analyzed for hypotonic shock response (HSR), P-selectin, and glycoprotein (GP)Ib expression and evaluation of coagulation by FOR. Swirling, HSR, and percent GPIb-expressing PLTs were well maintained for 7 days, whereas glucose decreased and lactate increased significantly during storage for both Spectra and Trima PCs. Percent P-selectin-expressing cells increased to the same extent in both types of PCs during storage. pH increased between Day 0 and Day 1 but then decreased. The clotting time remained constant throughout the storage period whereas the development of elasticity was reduced on Days 5 and 7 compared to Day 1 (p < 0.05) for both types of PCs. The results indicate that the PLT quality after storage for 7 days is well preserved, although activation of PLTs occurs during storage as assessed by in vitro tests. No difference in PLT quality was observed between Spectra- and Trima-produced PCs.

In vitro function of platelet concentrates prepared after filtration of whole blood or buffy coat pools

Data on the quality of platelet concentrates (PC) produced by the buffy coat method and stored beyond 5 days in plasma are limited. We therefore evaluated the quality of PCs prepared by leucocyte depletion of whole blood (Terumo WBSP, n = 10) or a buffy coat pool (Pall Autostop, n = 10), and stored for 7 days in plasma by assessing platelet parameters and markers of platelet activation. In both types of PC, levels of glucose decreased during storage but were not totally depleted (> 11 mM on day 7). In contrast, lactate levels increased on storage and was consistently < 20 mM throughout, with pH maintained at > 6.8 in all units. Hypotonic shock response scores were > 47% in all units at day 7. On day 1, markers of platelet activation were significantly higher in WBSP PC, but by day 7 were similar for percentage CD63+ and CD62P + (40%) with levels of platelet microparticles and annexin V binding two-fold higher in WBSP. The expression of CD61 did not alter during storage and the percentage of platelets expressing CD42b was > 88% in all units on day 7. RANTES (Regulated on activation, normal, T-cell expressed and secreted) and TGFbeta released from platelets by day 7 was < 800 ng/ml and 90 ng/ml, respectively. C3a(desarg) increased throughout storage in both types of PC, but without a commensurate increase in the terminal complex SC5b-9 or activation of factor XII. Our data indicates that the in vitro characteristics of PCs prepared using these methods is maintained over storage for 7 days in plasma and is not associated with significant deterioration of platelet function. ONE SENTENCE SUMMARY: In vitro function of platelet concentrates prepared by either filtration of whole blood, or pooled buffy coats.

Improved platelet compatiblity of water vapour glow discharge treated non-woven poly(ethylene terephthalate) leukocyte-reduction filters for different types of platelet concentrates.

Non-woven poly[ethylene terephthalate] (NW-PET) filter fabric, usually used for leucocyte removal of red cells, was modified by water vapour glow discharge (WVGD) treatment to improve platelet compatibility. Modified filter material was evaluated with different kinds of platelet concentrates (PCs). In addition, modified filter materials were gamma-sterilized and tested after different time intervals at different storage conditions. Modification of the filter material resulted in an improved platelet recovery after filtration of PC from 57 to about 80%. No significant difference in platelet recovery was observed when filtering either freshly prepared (79 +/- 3.5%, mean +/- SD), overnight-stored single BC-PC (78 +/- 3.3%), overnight-stored single PRP-PC (75 +/- 8.8%) or overnight-stored pooled BC-PC (79 +/- 8.9%). However, freshly prepared pooled BC-PC gave a significantly higher platelet recovery (84 +/- 3.5%). Leukocyte depletion did not differ significantly between the different types of PC. gamma-Sterilization and subsequent storage of the modified filter material for 5, 14 and 26 weeks at 20 degrees C or 37 degrees C had no significant influence on the filtration results of overnight-stored pooled BC-PC. The results of the present study show that WVGD-treated NW-PET is platelet compatible and can be used for leucocyte removal from preferably BC-PC. It can be gamma-sterilized and stored for at least 6 months prior to filtration without affecting the platelet recovery and leucocyte removal.

Are All Leucodepleted Platelet Concentrates Equivalent?

Background and Objectives: A number of technologies are available for the production of leucocyte–depleted platelet concentrates (PCs). This study compared the characteristics of PCs prepared by three commonly used techniques. Materials and Methods: In total, fifteen units of leucoyte–depleted PCs prepared by the Cobe LRS Turbo apheresis system, Haemonetics MCS+ with in–line filter and filtration of PCs derived from pooled buffy coats (BCs) were transferred into the same standard container. Markers to assess status/activation and microvesiculation of platelets as well as platelet injury were measured. Results: pH was well maintained in all types of PCs. The expression of CD62P was higher in Cobe LRS Turbo on day 1 but became equivalent between the three methods on day 5. A significant correlation was found between the expression of CD62P on platelet surface and soluble CD62P in the plasma. The degree of phosphatidylserine (PS) exposure was slightly higher in Cobe LRS Turbo and BC–PCs than Haemonetics MCS+ on day 1. However, on day 5 both apheresis PC values were higher than BC–PCs. A significant correlation was found between PS exposure and microvesiculation. Conclusion: Leucodepleted PCs prepared by the three methods were different in terms of storage lesion and microvesiculation. The clinical significance of these findings remains to be investigated.

Are All Leucodepleted Platelet Concentrates Equivalent?

Abstract Background and Objectives: A number of technologies are available for the production of leucocyte‐depleted platelet concentrates (PCs). This study compared the characteristics of PCs prepared by three commonly used techniques. Materials and Methods: In total, fifteen units of leucoyte‐depleted PCs prepared by the Cobe LRS Turbo apheresis system, Haemonetics MCS+ with in‐line filter and filtration of PCs derived from pooled buffy coats (BCs) were transferred into the same standard container. Markers to assess status/activation and microvesiculation of platelets as well as platelet injury were measured. Results: pH was well maintained in all types of PCs. The expression of CD62P was higher in Cobe LRS Turbo on day 1 but became equivalent between the three methods on day 5. A significant correlation was found between the expression of CD62P on platelet surface and soluble CD62P in the plasma. The degree of phosphatidylserine (PS) exposure was slightly higher in Cobe LRS Turbo and BC‐PCs than Haemonetics MCS+ on day 1. However, on day 5 both apheresis PC values were higher than BC‐PCs. A significant correlation was found between PS exposure and microvesiculation. Conclusion: Leucodepleted PCs prepared by the three methods were different in terms of storage lesion and microvesiculation. The clinical significance of these findings remains to be investigated.

Cytokine levels in platelet concentrates: quantitation by bioassays and immunoassays

Some adverse reactions to the transfusion of platelet concentrates (PCs) cannot be attributed to antibodies against blood cells or to subclinical microbial agents. It has been suggested that leucocyte-derived inflammatory cytokines such as interleukin (IL)-1, IL-6 and tumour necrosis factor (TNF) may contribute to a larger number of unexplained non-antibody-mediated adverse reactions. Three types of PCs, containing different levels of leucocytes, are currently produced. Filtration is used on demand to further reduce leucocyte contamination of these components. we have monitored the plasma of PCs prepared by the platelet-rich plasma method (PRP), the buffy-coat method or by apheresis for IL-6, IL-1, transforming growth factor-beta (TGF-beta), TNF and interferon gamma (IFN gamma). Biologically active IL-6 increased in stored PRP-PCs from a mean of 140 pg/ml on day 1 to 2395 pg/ml on day 5/6. Elevated levels of IL-8, as detected by immunoassay, were evident in PRP-PCs during routine storage under blood bank conditions. Small amounts of immunoreactive IL-1 with only minimal biological activity were present in some PRP-PCs by day 5/6. No significant increase in the levels of IL-8, IL-6 or IL-1 were seen in buffy-coat PCs during storage for 5/6 d. For apheresis PCs, an increase in IL-8 content, but not in IL-6 over 6 d was observed. In all three types of PCs, elevated amounts of both bioactive and immunoreactive TGF beta were present, but there was no evidence of any biologically active or immunoreactive TNF alpha. Pre-storage filtration of PRP-PCs for depletion of leucocytes prevented the increase in IL-8 and IL-6 levels of these PCs. Our results show that leucocyte reduction by buffy-coat method reduces cytokine levels to a comparable level to filtered or apheresis PCs, containing low levels of leucocytes, but use of these PCs in minimizing the severity and incidence of reactions in recipients will require clinical evaluation. This is the first comprehensive and comparative study which, on the basis of biological activity of cytokines, directly indicates that the mode of platelet production grossly influences the levels of cytokines.

Analysis of platelet factor 3 in platelet concentrates stored for transfusion.

The amount of platelet factor 3 (PF3) activity expressed in stored platelet concentrates (PC) was measured in conjunction with extracellular LDH levels. Standard manual techniques for preparation of PC resulted in PF3 and LDH levels remarkably higher than those observed in PC prepared by apheresis or special manual plateletpheresis. During storage of PC, PF3 activity rose 2- to 10-fold, while LDH levels rose less than 2-fold over starting values. Loss of LDH and appearance of PF3 expressed as a percent of total per platelet were significantly correlated only in standard, manual PC. Approximately half of the PF3 activity observed in any type of PC remained in the supernatant plasma after centrifugation. Upon gel filtration, the supernatant PF3 activity eluted in a high molecular weight peak containing phosphate and light-scattering material. Our findings indicate that platelets in standard, citrated PC express PF3 in amounts that approach that of frozen-thawed (lysed) platelets; however, the manner in which the PF3 activity appears suggests that stored platelets undergo a combination of activation and damage processes.