Results of clinical effectiveness of conventional versus Mirasol-treated Apheresis Platelets in Patients with Hypoproliferative Thrombocytopenia (MiPLATE) trial.

BACKGROUND: The Mirasol® Pathogen Reduction Technology System was developed to reduce transfusion-transmitted diseases in platelet (PLT) products. STUDY DESIGN AND METHODS: MiPLATE trial was a prospective, multicenter, controlled, randomized, non-inferiority (NI) study of the clinical effectiveness of conventional versus Mirasol-treated Apheresis PLTs in participants with hypoproliferative thrombocytopenia. The novel primary endpoint was days of ≥Grade 2 bleeding with an NI margin of 1.6. RESULTS: After 330 participants were randomized, a planned interim analysis of 297 participants (145 MIRASOL, 152 CONTROL) receiving ≥1 study transfusion found a 2.79-relative rate (RR) in the MIRASOL compared to the CONTROL in number of days with ≥Grade 2 bleeding (95% confidence interval [CI] 1.67-4.67). The proportion of subjects with ≥Grade 2 bleeding was 40.0% (n = 58) in MIRASOL and 30.3% (n = 46) in CONTROL (RR = 1.32, 95% CI 0.97-1.81, p = .08). Corrected count increments were lower (p < .01) and the number of PLT transfusion episodes per participant was higher (RR = 1.22, 95% CI 1.05-1.41) in MIRASOL. There was no difference in the days of PLT support (hazard ratio = 0.86, 95% CI 0.68-1.08) or total number of red blood cell transfusions (RR = 1.12, 95% CI 0.91-1.37) between MIRASOL versus CONTROL. Transfusion emergent adverse events were reported in 119 MIRASOL participants (84.4%) compared to 133 (82.6%) participants in CONTROL (p = NS). DISCUSSION: This study did not support that MIRASOL was non-inferior compared to conventional platelets using the novel endpoint number of days with ≥Grade 2 bleeding in MIRASOL when compared to CONTROL.

Elucidating granulocytic myeloid-derived suppressor cell heterogeneity during Staphylococcus aureus biofilm infection.

Myeloid-derived suppressor cells (MDSCs) are pathologically activated immature myeloid cells with immunosuppressive activity that expand during chronic inflammation, such as cancer and prosthetic joint infection (PJI). Myeloid-derived suppressor cells can be broadly separated into 2 populations based on surface marker expression and function: monocytic myeloid-derived suppressor cells (M-MDSCs) and granulocytic myeloid-derived suppressor cells (G-MDSCs). Granulocytic myeloid-derived suppressor cells are the most abundant leukocyte infiltrate during PJI; however, how this population is maintained in vivo and cellular heterogeneity is currently unknown. In this study, we identified a previously unknown population of Ly6G+Ly6C+F4/80+MHCII+ MDSCs during PJI that displayed immunosuppressive properties ex vivo. We leveraged F4/80 and MHCII expression by these cells for further characterization using cellular indexing of transcriptomes and epitopes by sequencing, which revealed a distinct transcriptomic signature of this population. F4/80+MHCII+ MDSCs displayed gene signatures resembling G-MDSCs, neutrophils, and monocytes but had significantly increased expression of pathways involved in cytokine response/production, inflammatory cell death, and mononuclear cell differentiation. To determine whether F4/80+MHCII+ MDSCs represented an alternate phenotypic state of G-MDSCs, Ly6G+Ly6C+F4/80-MHCII- G-MDSCs from CD45.1 mice were adoptively transferred into CD45.2 recipients using a mouse model of PJI. A small percentage of transferred G-MDSCs acquired F4/80 and MHCII expression in vivo, suggesting some degree of plasticity in this population. Collectively, these results demonstrate a previously unappreciated phenotype of F4/80+MHCII+ MDSCs during PJI, revealing that a granulocytic-to-monocytic transition can occur during biofilm infection.

Therapeutic leukocytapheresis for leukostasis in chronic lymphocytic leukemia: A case report and literature review.

Chronic lymphocytic leukemia (CLL) is a clonal mature B-cell neoplasm with a typically indolent clinical course. Though most clinicians follow these neoplasms through observation alone, an aggressive transformation to prolymphocytic leukemia, diffuse large-B-cell lymphoma (Richter transformation) or classical Hodgkin lymphoma requires immediate attention. We present a case of extreme leukocytosis (>1 million/µL) in a previously diagnosed CLL patient. Due to symptomatic leukostasis, she was started on cytoreductive therapies including leukocytapheresis. After three rounds of leukocytapheresis (LCP) and concurrent chemotherapy, her white blood cell count decreased from a maximum 1262 × 103 /µL to 574 × 103 /µL. To our knowledge, CLL with symptomatic leukostasis that required therapeutic LCP is rarely reported in literature. We propose that therapeutic LCP is of value in such rare, yet dangerous settings like our case.

Two acute psychiatric emergencies and prevalence of mental health disorders at an outpatient apheresis clinic: Implications for apheresis practitioners.

The prevalence of mental health disorders among apheresis patients is unknown. Patients with chronic conditions treated with apheresis in the outpatient setting often see their apheresis healthcare professionals more frequently than their referring physicians. In addition, many apheresis patients are on medications with psychiatric side effects such as steroids. Given the frequent interactions of apheresis practitioners with outpatients, psychiatric issues may be encountered. To highlight these issues, we report two psychiatric emergencies that occurred in an outpatient apheresis clinic. Additionally, the prevalence of mental health diagnoses in our outpatient clinic was determined to help estimate the exposure that apheresis teams have to patients with mental health diagnoses. Practical recommendations for apheresis practitioners when encountering psychiatric emergencies are summarized.

Cerebral Venous Sinus Thrombosis due to Thrombosis with Thrombocytopenia Syndrome Following Ad26.COV2.S: A First Real-World Case Report of a Male Subject.

Thrombosis with Thrombocytopenia Syndrome (TTS) or Vaccine-induced Immune Thrombotic Thrombocytopenia (VITT) had been reported in patients receiving the Ad26.COV2.S vaccination (Johnson & Johnson [J&J]/Janssen) vaccine. They frequently presented with cerebral venous sinus thrombosis (CVST), but venous or arterial thrombosis at other locations can be present. The majority of those affected are younger adult females. Therefore, after a brief pause from April 13-23, 2021, the Centers for Disease Control and Prevention (CDC) and the U.S. Food and Drug Administration (FDA) recommended caution in using this vaccine in females under 50 years. Based on the reported 28 cases of TTS after this vaccination (data till April 21, 2021) by CDC, 22 were females (78%), and 6 were male. None of those males had CVST but had thrombosis at other locations. We report the first case of a young male with TTS and CVST following Ad26.COV2.S vaccine presented with severe headache and diagnosed with acute right transverse and sigmoid cerebral venous sinus thrombosis, multiple right-sided pulmonary emboli, and right hepatic vein thrombosis. He was treated with parenteral anticoagulation with argatroban and intravenous immune globulin with the improvement of his symptoms. A heparin-induced thrombocytopenia with thrombosis (HITT) like syndrome caused by the genesis of a platelet-activating autoantibody against platelet factor 4 (PF4) triggered by adenoviral vector-based COVID-19 vaccinations is understood to be the underlying pathophysiology. TTS with CVST should be considered when patients present with headaches, stroke-like neurological symptoms, thrombocytopenia, and symptom onset 6-15 days after Ad26.COV2.S vaccination.

Persistence of Ad26.COV2.S-associated vaccine-induced immune thrombotic thrombocytopenia (VITT) and specific detection of VITT antibodies.

Rare cases of COVID-19 vaccinated individuals develop anti-platelet factor 4 (PF4) antibodies that cause thrombocytopenia and thrombotic complications, a syndrome referred to as vaccine-induced immune thrombotic thrombocytopenia (VITT). Currently, information on the characteristics and persistence of anti-PF4 antibodies that cause VITT after Ad26.COV2.S vaccination is limited, and available diagnostic assays fail to differentiate Ad26.COV2.S and ChAdOx1 nCoV-19-associated VITT from similar clinical disorders, namely heparin-induced thrombocytopenia (HIT) and spontaneous HIT. Here we demonstrate that while Ad26.COV2.S-associated VITT patients are uniformly strongly positive in PF4-polyanion enzyme-linked immunosorbent assays (ELISAs); they are frequently negative in the serotonin release assay (SRA). The PF4-dependent p-selectin expression assay (PEA) that uses platelets treated with PF4 rather than heparin consistently diagnosed Ad26.COV2.S-associated VITT. Most Ad26.COV2.S-associated VITT antibodies persisted for >5 months in PF4-polyanion ELISAs, while the PEA became negative earlier. Two patients had otherwise unexplained mild persistent thrombocytopenia (140-150 x 103 /µL) 6 months after acute presentation. From an epidemiological perspective, differentiating VITT from spontaneous HIT, another entity that develops in the absence of proximate heparin exposure, and HIT is important, but currently available PF4-polyanion ELISAs and functional assay are non-specific and detect all three conditions. Here, we report that a novel un-complexed PF4 ELISA specifically differentiates VITT, secondary to both Ad26.COV2.S and ChAdOx1 nCoV-19, from both spontaneous HIT, HIT and commonly-encountered HIT-suspected patients who are PF4/polyanion ELISA-positive but negative in functional assays. In summary, Ad26.COV2.S-associated VITT antibodies are persistent, and the un-complexed PF4 ELISA appears to be both sensitive and specific for VITT diagnosis.

Assessment of Specimen Pooling to Conserve SARS CoV-2 Testing Resources.

Objectives To establish the optimal parameters for group testing of pooled specimens for the detection of SARS-CoV-2. Methods The most efficient pool size was determined to be 5 specimens using a web-based application. From this analysis, 25 experimental pools were created using 50 microliter from one SARS-CoV-2 positive nasopharyngeal specimen mixed with 4 negative patient specimens (50 microliter each) for a total volume of 250 microliter l. Viral RNA was subsequently extracted from each pool and tested using the CDC SARS-CoV-2 RT-PCR assay. Positive pools were consequently split into individual specimens and tested by extraction and PCR. This method was also tested on an unselected group of 60 nasopharyngeal specimens grouped into 12-pools. Results All 25 pools were positive with Cycle threshold (Ct) values within 0 and 5.03 Ct of the original individual specimens. The analysis of 60 specimens determined that two pools were positive followed by identification of two individual specimens among the 60 tested. This testing was accomplished while using 22 extractions/PCR tests, a savings of 38 reactions. Conclusions When the incidence rate of SARS-CoV-2 infection is 10% or less, group testing will result in the saving of reagents and personnel time with an overall increase in testing capability of at least 69%.

3D-Printing to Address COVID-19 Testing Supply Shortages.

The recent SARS-CoV-2 outbreak has placed immense pressure on supply chains, including shortages in nasopharyngeal (NP) swabs. Here, we report our experience of using 3D-printing to rapidly develop and deploy custom-made NP swabs to address supply shortages at our healthcare institution.

Assessment of Specimen Pooling to Conserve SARS CoV-2 Testing Resources.

OBJECTIVES: To establish the optimal parameters for group testing of pooled specimens for the detection of SARS-CoV-2. METHODS: The most efficient pool size was determined to be five specimens using a web-based application. From this analysis, 25 experimental pools were created using 50 µL from one SARS-CoV-2 positive nasopharyngeal specimen mixed with 4 negative patient specimens (50 µL each) for a total volume of 250 µL. Viral RNA was subsequently extracted from each pool and tested using the CDC SARS-CoV-2 RT-PCR assay. Positive pools were consequently split into individual specimens and tested by extraction and PCR. This method was also tested on an unselected group of 60 nasopharyngeal specimens grouped into 12 pools. RESULTS: All 25 pools were positive with cycle threshold (Ct) values within 0 and 5.03 Ct of the original individual specimens. The analysis of 60 specimens determined that 2 pools were positive followed by identification of 2 individual specimens among the 60 tested. This testing was accomplished while using 22 extractions/PCR tests, a savings of 38 reactions. CONCLUSIONS: When the incidence rate of SARS-CoV-2 infection is 10% or less, group testing will result in the saving of reagents and personnel time with an overall increase in testing capability of at least 69%.

Characterization of Ebola convalescent plasma donor immune response and psoralen treated plasma in the United States.

BACKGROUND: In 2014, passive immunization by transfusion of Ebola convalescent plasma (ECP) was considered for treating patients with acute Ebola virus disease (EVD). Early Ebola virus (EBOV) seroconversion confers a survival advantage in natural infection, hence transfusion of ECP plasma with high levels of neutralizing EBOV antibodies is a potential passive immune therapy. Techniques to reduce the risk of other transfusion-transmitted infections (TTIs) are warranted as recent ECP survivors are ineligible as routine blood donors. As part of an ongoing clinical trial to evaluate the safety and effectiveness of ECP, the impact of amotosalen/UVA pathogen reduction technology (PRT) on EBOV antibody characteristics was examined. STUDY DESIGN AND METHODS: Serum and plasma samples were collected from EVD-recovered subjects at multiple timepoints and evaluated by ELISA for antibodies to recombinant EBOV glycoprotein (GP) and irradiated whole EBOV antigen, as well as for EBOV microneutralization, classic plaque reduction neutralization test (PRNT) and EBOV pseudovirion neutralization assay (PsVNA) activity. RESULTS: Six subjects donated 40 individual ECP units. Substantial antibody titers and neutralizing activity results were demonstrated but were generally lower for the ACD plasma samples compared to the serum samples. Anti-EBOV titers by all assays remained essentially unchanged after PRT. CONCLUSION: Treatment of ECP with PRT to reduce the risk of TTI did not significantly reduce EBOV IgG antibody titers or neutralizing activity. Although ECP was used in the treatment of repatriated patients, no PRT units from this study were transfused to EVD patients. This inventory of PRT-treated ECP is currently available for future clinical evaluation.

Diverse Mechanisms of BRAF Inhibitor Resistance in Melanoma Identified in Clinical and Preclinical Studies.

BRAF inhibitor therapy may provide profound initial tumor regression in metastatic melanoma with BRAF V600 mutations, but treatment resistance often leads to disease progression. A multi-center analysis of BRAF inhibitor resistant patient tissue samples detected genomic changes after disease progression including multiple secondary mutations in the MAPK/Erk signaling pathway, mutant BRAF copy number gains, and BRAF alternative splicing as the predominant putative mechanisms of resistance, but 41.7% of samples had no known resistance drivers. In vitro models of BRAF inhibitor resistance have been developed under a wide variety of experimental conditions to investigate unknown drivers of resistance. Several in vitro models developed genetic alterations observed in patient tissue, but others modulate the response to BRAF inhibitors through increased expression of receptor tyrosine kinases. Both secondary genetic alterations and expression changes in receptor tyrosine kinases may increase activation of MAPK/Erk signaling in the presence of BRAF inhibitors as well as activate PI3K/Akt signaling to support continued growth. Melanoma cells that develop resistance in vitro may have increased dependence on serine or glutamine metabolism and have increased cell motility and metastatic capacity. Future studies of BRAF inhibitor resistance in vitro would benefit from adhering to experimental parameters that reflect development of BRAF inhibitor resistance in patients through using multiple cell lines, fully characterizing the dosing strategy, and reporting the fold change in drug sensitivity.

Serendipitous Discovery of Factor VII Deficiency and the Ensuing Dilemma.

Congenital factor VII deficiency is a challenging disorder to manage, as it is associated with varied genotypes that do not clinically correlate with a bleeding phenotype. Individuals with severe factor VII deficiency (FVII: c <1%) might be asymptomatic, while patients with moderate deficiency (FVII: c level >5%) may experience severe hemorrhages. In modern medicine, due to extensive routine pre-operative laboratory testing, clinically asymptomatic patients without any bleeding history might be incidentally discovered, raising clinical dilemmas. Careful consideration of bleeding versus thrombosis risk has to be made in such cases, especially in the elderly. Clinical history of no prior bleeding complications may be a reassuring factor. Minimal required replacement dosing of recombinant activated factor VII can be given peri-operatively in such situations, with close monitoring.

MVP immunohistochemistry is a useful adjunct in distinguishing leiomyosarcoma from leiomyoma and leiomyoma with bizarre nuclei.

Morphologically, distinguishing between leiomyoma (LM) and leiomyosarcoma (LMS) is not always straightforward, especially with benign variants such as bizarre leiomyoma (BLM). To identify potential markers of malignancy in uterine smooth muscle tumors, proteomic studies were performed followed by assessment of protein expression by immunohistochemistry. Archival formalin-fixed, paraffin-embedded tissues from tumors (n = 23) diagnosed as LM, BLM, and LMS (using published criteria) were selected for the study. Sequential window acquisition of all theoretical fragment ion spectra mass spectrometry was applied to pooled samples of formalin-fixed, paraffin-embedded LM and LMS tumor tissue to assay the relative protein quantities and look for expression patterns differentiating the 2 tumor types. A total of 592 proteins were quantified, and 10 proteins were differentially expressed between LM and LMS. Select proteins were chosen for evaluation by immunohistochemistry (IHC) based on antibody availability and biologic relevance in the literature. IHC was performed on a tissue microarray, and intensity was evaluated using imaging software. Major vault protein (MVP) and catechol O-methyltransferase had 3.05 and 13.94 times higher expression in LMS relative to LM by sequential window acquisition of all theoretical fragment ion spectra mass spectrometry, respectively. By IHC, MVP (clone 1014; Santa Cruz Biotechnology, Dallas, TX) was found to be 50% sensitive and 100% specific when comparing LMS to LM. Catechol O-methyltransferase (clone FL-271; Santa Cruz Biotechnology) had a sensitivity of 38% and a specificity of 88%. Six of 7 BLM had expression of MVP similar to LM. Immunohistochemical staining for MVP is a useful adjunct in distinguishing LMS from LM and BLM in difficult cases.

Use of standard laboratory methods to obviate routine dithiothreitol treatment of blood samples with daratumumab interference.

CONCLUSIONS: Daratumumab is an antibody currently used in the treatment of patients with refractory multiple myeloma. Blood samples from patients being treated with daratumumab may show panreactivity during pre-transfusion testing. To facilitate the provision of blood components for such patients, it is recommended that a baseline phenotype or genotype be established prior to starting treatment with daratumumab. If patient red blood cells (RBCs) require phenotyping after the start of daratumumab treatment, dithiothreitol (DTT) treatment of the patient's RBCs should be performed. The medical charts of four patients treated with daratumumab were reviewed. The individual number of doses ranged from 1 to 14; patient age ranged from 55 to 78 years; two men and two women were included in the review. Type and screen data were obtained from samples collected over 33 encounters with a range of 1 to 13 encounters per patient. All samples were tested initially by automated solid-phase testing. Any reactivity with solid phase led to tube testing with either low-ionic-strength saline, polyethylene glycol, or both. If incubation failed to eliminate the reactivity, the sample was sent to a reference laboratory for DTT treatment and phenotyping. Of the 33 samples tested, 23 (69.7%) samples had reactivity in solid-phase testing. In 8 of the 10 samples that did not react in solid-phase, testing was conducted more than four half-lives after the last dose of daratumumab. Of the 23 that had reactivity in solid-phase, 16 (69.6%) samples demonstrated loss of reactivity using common laboratory methods. For the seven patients whose sample reactivity was not initially eliminated, six were provided with phenotypically matched blood based on prior molecular testing. Only one sample was sent out for DTT treatment. These results suggest that daratumumab interference with pre-transfusion testing can be addressed using common laboratory methods. This finding could save time and money for laboratories that do not have DTT available.

Therapeutic plasma exchange and pregnancy: A case report and guidelines for performing plasma exchange in a pregnant patient.

Therapeutic plasma exchange (TPE) has been demonstrated to be of significant clinical value in a number of diseases and conditions, with well-established guidelines and recommendations. However, technical support in providing this procedure for pregnant patients is largely absent from these recommendations, leaving therapeutic apheresis practitioners without guidance to safely and adequately treat appropriate conditions in this important patient population. Here, we describe our experience in treating a 35-year-old pregnant patient with relapsing-remitting multiple sclerosis with TPE. Additionally, we outline the principle considerations when developing her treatment plan, and we provide recommendations for apheresis practitioners when performing TPE in pregnant patients. J. Clin. Apheresis 32:191-195, 2017. © 2016 Wiley Periodicals, Inc.

Requirement for a Pathologist's Second Signature Limits Inappropriate Inpatient Thrombophilia Testing.

Thromboembolism is a condition that leads to the hospitalization of thousands of patients in the United States annually. Recent guidelines suggest that testing for hereditary, acquired and combined forms of thrombophilia be delayed following hospitalization for a first-time acute thrombotic event. Instead, thrombophilia testing would be performed in an outpatient setting, at least 1 month after discontinuation of anticoagulant therapy or 3 months after the thrombotic event, on the understanding that anticoagulation may affect some testing. Here, we provide our experience in instituting a system-wide policy change to limit thrombophilia testing in the inpatient setting. The policy change implemented led to a 90% reduction in number of tests ordered. We discuss the cost savings realized by limiting testing. These changes cost nothing to implement. Overall, limiting inpatient thrombophilia testing improves compliance with testing guidelines, provides better care for patients, and allows our institution to better utilize resources.

The Role of the Laboratory and Transfusion Service in the Management of Ebola Virus Disease.

The Ebola outbreak that began in 2013 infected and killed record numbers of individuals and created unprecedented challenges, including containment and treatment of the virus in resource-strained West Africa as well as the repatriation and treatment for patients in the United States and Europe. Valuable lessons were learned, especially the important role that the laboratory and transfusion service plays in the treatment for patients with Ebola virus disease (EVD) by providing data for supportive care and fluid resuscitation as well as the generation of investigational therapies such as convalescent plasma (CP). To provide treatment support, laboratories had to evaluate and update procedures to ensure the safety of laboratory personnel. Because there is no licensed EVD-specific treatment, CP was used in more than 99 patients with only 1 possible severe adverse event reported. However, given the biologic variability inherent in CP as well as the small number of patient treated in a nonrandomized fashion, the efficacy of CP in the treatment of EVD remains unknown.