Cryopreservation affects platelet macromolecular composition over time after thawing and differently impacts on cancer cells behavior in vitro.

Cryopreservation affects platelets' function, questioning their use for cancer patients. We aimed to investigate the biochemical events that occur over time after thawing to optimize transfusion timing and evaluate the effect of platelet supernatants on tumor cell behavior in vitro. We compared fresh (Fresh-PLT) with Cryopreserved platelets (Cryo-PLT) at 1 h, 3 h and 6 h after thawing. MCF-7 and HL-60 cells were cultured with Fresh- or 1 h Cryo-PLT supernatants to investigate cell proliferation, migration, and PLT-cell adhesion. We noticed a significant impairment of hemostatic activity accompanied by a post-thaw decrease of CD42b+ , which identifies the CD62P--population. FTIR spectroscopy revealed a decrease in the total protein content together with changes in their conformational structure, which identified two sub-groups: 1) Fresh and 1 h Cryo-PLT; 2) 3 h and 6 h cryo-PLT. Extracellular vesicle shedding and phosphatidylserine externalization (PS) increased after thawing. Cryo-PLT supernatants inhibited cell proliferation, impaired MCF-7 cell migration, and reduced ability to adhere to tumor cells. Within the first 3 hours after thawing, irreversible alterations of biomolecular structure occur in Cryo-PLT. Nevertheless, Cryo-PLT should be considered safe for the transfusion of cancer patients because of their insufficient capability to promote cancer cell proliferation, adhesion, or migration.

What is the context? Transfusion of Fresh platelets (Fresh-PLT) with prophylaxis purposes is common in onco-hematological patients.Cryopreservation is an alternative storage method that allows to extend platelet component shelf life and build supplies usable in case of emergency.It is well established that cryopreservation affects platelet function questioning their use in onco-hematological patients.It is still unknown how platelet impairment, induced by cryopreservation, occurs over time after thawing, nor how the by-products of PLT deterioration may impact on cancer cell behavior.What is new? In this study, we deeply characterized the functional and morphological changes induced by cryopreservation on platelets by comparing Fresh-PLT with Cryo-PLT at 1 h, 3 h and 6 h after thawing. Afterwards, we evaluated the effect of PLT supernatants on cancer cell behavior in vitro.The data presented show that within 3 hours after thawing Cryo-PLT undergo to irreversible macromolecular changes accompanied by increase of peroxidation processes and protein misfolding.After thawing the clot formation is reduced but still supported at all-time points measured, combined with unchanged phosphatidylserine expression and extracellular vesicles release over time.Cryo-PLT supernatants do not sustain proliferation and migration of cancer cells.WHAT is the impact? Cryo-PLT may be considered a precious back-up product to be used during periods of Fresh-PLT shortage to prevent bleeding in non-hemorrhagic patients.It is desirable to make it logistically feasible to transfuse cryopreserved platelets within 1 hour of thawing to maintain the platelets in their best performing condition.

A cohort study on the biochemical and haematological parameters of Italian blood donors as possible risk factors of COVID-19 infection and severe disease in the pre- and post-Omicron period.

To investigate the association between biochemical and blood parameters collected before the pandemic in a large cohort of Italian blood donors with the risk of infection and severe disease. We also focused on the differences between the pre- and post-Omicron spread in Italy (i.e., pre- and post-January 01, 2022) on the observed associations. We conducted an observational cohort study on 13750 blood donors was conducted using data archived up to 5 years before the pandemic. A t-test or chi-squared test was used to compare differences between groups. Hazard ratios with 95% confidence intervals for SARS-CoV-2 infection and severe disease were estimated using Cox proportional hazards models. Subgroup analyses stratified by sex, age and epidemic phase of first infection (pre- and post-Omicron spread) were examined. We confirmed a protective effect of groups B and O, while groups A and AB had a higher likelihood of infection and severe disease. However, these associations were only significant in the pre-Omicron period. We found an opposite behavior after Omicron spread, with the O phenotype having a higher probability of infection. When stratified by variant, A antigen appeared to protect against Omicron infection, whereas it was associated with an increased risk of infection by earlier variants. We were able to stratify for the SARS CoV-2 dominant variant, which revealed a causal association between blood group and probability of infection, as evidenced by the strong effect modification observed between the pre- and post-Omicron spread. The mechanism by which group A acts on the probability of infection should consider this strong effect modification.

Homologous platelet gel on radiation-induced dermatitis in a patient receiving head and neck radiotherapy plus cetuximab: A case report.

INTRODUCTION: Acute radiodermatitis is a significant complication of cancer radiotherapy, and platelet-based therapies are emerging as potential new treatments. MAIN SYMPTOMS AND IMPORTANT CLINICAL FINDINGS: In this report, we present the case of a patient with head and neck cancer undergoing radiotherapy combined with the monoclonal antibody cetuximab. After 4 weeks of this treatment, the patient developed cutaneous radiation dermatitis. Despite receiving standard treatment with corticosteroids and emollient cream, the lesion did not improve. MAIN DIAGNOSIS: cutaneous radiation dermatitis on head and neck cancer patient. THERAPEUTIC INTERVENTIONS: Topical application of platelet gel was initiated on the wound. From the second week of radiotherapy to the 4th week, homologous platelet-rich plasma was applied on the dermatitis using a bandage, 4 times a day. OUTCOMES: The topical treatment with homologous platelet gel resulted in complete healing of the radiodermatitis, including restoration of the epidermis, reepithelialization, and reduction in associated pain. CONCLUSION: homologous platelet gel might be an alternative to standard treatment of radiation dermatitis.

Mother-newborn ABO group discrepancy caused by a rare BW.17 variant.

Several ABO gene mutations are known to determine rare subgroups: these ABO variants are often responsible for weak or null phenotypes and may cause an incorrect determination of the serotype. Here we describe for the first time the phenotypic discrepancy of a rare B allele within the same Caucasian family that depends on the co-inheritance with A or H antigen. Blood samples from newborns, mothers, and grandmothers were analysed through routine serotype and genotype testing. Blood compatibility test was performed for red blood cells or serum of the grandmother. ABO exons were investigated through PCR and sanger sequencing. According to serology, the phenotype of the mother was AB, while it was O for the newborn. Genotype analysis confirmed that the mother was AB, while the newborn was found to be B. Sanger sequencing revealed the presence of a rare mutation in both individuals (784 G>A, D262N), corresponding to the ABO*BW.17 allele. The grandmother was found to have the same genotype/serotype of the newborn. Crossmatch testing suggested that subjects with this genotype/serotype might be considered O donors and recipients.

Platelet-rich Plasma Lysate for Treatment of Eye Surface Diseases.

Various ocular surface diseases are treated with blood-derived eye drops. Their use has been introduced in clinical practice because of their metabolite and growth factor content, which promotes eye surface regeneration. Blood-based eye drops can be prepared from different sources (i.e., whole blood or platelet apheresis donation), as well as with different protocols (e.g., different dilutions and freeze/thaw cycles). This variability hampers the standardization of clinical protocols and, consequently, the evaluation of their clinical efficacy. Detailing and sharing the methodological procedures may contribute to defining common guidelines. Over the last years, allogenic products have been diffusing as an alternative to the autologous treatments since they guarantee higher efficacy standards; among them, the platelet-rich plasma lysate (PRP-L) eye drops are prepared with simple manufacturing procedures. In the transfusion medicine unit at AUSL-IRCCS di Reggio Emilia, Italy, PRP-L is obtained from platelet-apheresis donation. This product is initially diluted to 0.3 x 109 platelets/mL (starting from an average concentration of 1 x 109 platelets/mL) in 0.9% NaCl. Diluted platelets are frozen/thawed and, subsequently, centrifuged to eliminate debris. The final volume is split into 1.45 mL aliquots and stored at -80 °C. Before being dispensed to patients, eye drops are tested for sterility. Patients may store platelet lysates at -15 °C for up to 1 month. The growth factor composition is also assessed from randomly selected aliquots, and the mean values are reported here.

Apheresis Platelet Rich-Plasma for Regenerative Medicine: An In Vitro Study on Osteogenic Potential.

Background: Platelet-Rich Plasma (PRP) induces bone regeneration; however, there is low evidence supporting its efficacy in bone healing. The lack of a standardized protocol of administration represents the main obstacle to its use in the clinical routine for bone defects' treatment. The purpose of this study was to characterize PRP and elucidate its osteogenic potential. Methods: Platelet count, fibrinogen levels, and growth factors concentration were measured in PRP obtained by four apheresis procedures. HOB-01-C1, a pre-osteocytic cell line, was used to examine the effects of different PRP dilutions (from 1% to 50%) on cell viability, growth, and differentiation. Gene expression of RUNX2, PHEX, COL1A1, and OCN was also assayed. Results: PRP showed a mean 4.6-fold increase of platelets amount compared to whole blood. Among the 36 proteins evaluated, we found the highest concentrations for PDGF isoforms, EGF, TGF-ß and VEGF-D. PDGF-AA positively correlated with platelet counts. In three of the four tested units, 25% PRP induced a growth rate comparable to the positive control (10% FBS); whereas, for all the tested units, 10% PRP treatment sustained differentiation. Conclusions: This study showed that PRP from apheresis stimulates proliferation and differentiation of pre-osteocyte cells through the release of growth factors from platelets.