Anti-PF4 ELISA-Negative, SRA-Positive Heparin-Induced Thrombocytopenia.

Heparin products are frequently used in the inpatient setting to prevent and treat venous thromboembolism, but they simultaneously put patients at risk of developing heparin-induced thrombocytopenia (HIT). The 4Ts score determines the pretest probability of HIT. Diagnosis is made with a screening antiplatelet factor (PF4) immunoassay and the serotonin-release assay (SRA) as a confirmatory test. Anti-PF4 assays have high sensitivity (98%) but lower specificity (50%) and result in frequent false-positive tests. We present a rare case from our institution of a patient with anti-PF4-Polyanion ELISA-negative, SRA-positive HIT and describe the challenges in making a timely diagnosis in this case.

Successful Treatment of Refractory Post-Transplant Lymphoproliferative Disorder With Chimeric Antigen Receptor T-Cell Therapy in a Heart Transplant Recipient.

Post-transplant lymphoproliferative disorders (PTLDs) are opportunistic malignancies that complicate the success of hematopoietic stem cell or solid organ transplantation. These disorders often arise post-transplant due to the immunosuppression required for minimizing the risk of rejection of donor tissue. First-line treatment of these disorders includes limiting immunosuppression when permissible. Subsequent treatment includes the use of monoclonal anti-CD20 antibody (rituximab), and/or combination chemotherapy. Chimeric antigen receptor (CAR) T-cell therapy has revolutionized the treatment paradigm in many lymphoid malignancies. It is not approved for PTLD due to exclusion of PTLD patients from pivotal clinical trials. Also, its utilization post-transplant can be complex and multidisciplinary care is of utmost importance for successful administration of a potentially curative treatment. We present a 68-year-old patient with history of heart transplant for non-ischemic cardiomyopathy, diagnosed with PTLD that was refractory to treatment using current guidelines until successfully receiving CAR T-cell therapy.

Postinfusion PD-1+ CD8+ CAR T cells identify patients responsive to CD19 CAR T-cell therapy in non-Hodgkin lymphoma.

ABSTRACT: Chimeric antigen receptor (CAR) T-cell therapy has revolutionized treatment for relapsed/refractory B-cell non-Hodgkin lymphoma (NHL). Robust biomarkers and a complete understanding of CAR T-cell function in the postinfusion phase remain limited. Here, we used a 37-color spectral flow cytometry panel to perform high dimensional single-cell analysis of postinfusion samples in 26 patients treated with CD28 costimulatory domain containing commercial CAR T cells for NHL and focused on computationally gated CD8+ CAR T cells. We found that the presence of postinfusion Programmed cell death protein 1 (PD-1)+ CD8+ CAR T cells at the day 14 time point highly correlated with the ability to achieve complete response (CR) by 6 months. Further analysis identified multiple subtypes of CD8+ PD-1+ CAR T cells, including PD-1+ T cell factor 1 (TCF1)+ stem-like CAR T cells and PD-1+ T-cell immunoglobulin and mucin-domain containing-3 (TIM3)+ effector-like CAR T cells that correlated with improved clinical outcomes such as response and progression-free survival. Additionally, we identified a subset of PD-1+ CD8+ CAR+ T cells with effector-like function that was increased in patients who achieved a CR and was associated with grade 3 or higher immune effector cell-associated neurotoxicity syndrome. Here, we identified robust biomarkers of response to CD28 CAR T cells and highlight the importance of PD-1 positivity in CD8+ CAR T cells after infusion in achieving CR.

Prophylactic Anticoagulation in Patients With Pancreatic Adenocarcinoma: A Single Tertiary Care Center Retrospective QI Project.

BACKGROUND/AIM: A well-known complication of pancreatic adenocarcinoma (PDAC) is venous thromboembolism (VTE). The Khorana score is used as a tool to help determine the role of primary prophylaxis (PPx) in cancer patients with VTE. This study compared outcomes in PDAC patients who received primary PPx (anticoagulation) versus those who did not. PATIENTS AND METHODS: PDAC patients from 2017-2019 at Allegheny General Hospital were retrospectively reviewed. Descriptive statistics were presented via medians with interquartile ranges for continuous variables and percentages for categorical variables. Predictors of VTE development were determined using univariable and multivariable logistic regression models. T-tests and Chi-square tests were used to compare means and percentages, respectively. RESULTS: A total of 102 patients with full VTE PPx data were reviewed. At least one VTE event was identified in 29 patients (28.2%). A total of 4 out of these 29 patients (13.8%) were on PPx anticoagulation. Death secondary to VTE occurred in one patient without PPx. Two (2.0%) patients experienced bleeding events of those prescribed VTE PPx. On univariable analysis, stage IV disease, planned surgery, and unresectable disease were predictors of VTE development. On multivariate analysis, total pancreatectomy was a predictor of VTE development. There was no difference in average time to progression amongst patients who had developed VTE versus those who did not. CONCLUSION: The Khorana score for VTE PPx in PDAC patients in underutilized.

Recent Advances and Challenges in Cancer Immunotherapy.

Cancer immunotherapy has revolutionized the field of oncology in recent years. Harnessing the immune system to treat cancer has led to a large growth in the number of novel immunotherapeutic strategies, including immune checkpoint inhibition, chimeric antigen receptor T-cell therapy and cancer vaccination. In this review, we will discuss the current landscape of immuno-oncology research, with a focus on elements that influence immunotherapeutic outcomes. We will also highlight recent advances in basic aspects of tumor immunology, in particular, the role of the immunosuppressive cells within the tumor microenvironment in regulating antitumor immunity. Lastly, we will discuss how the understanding of basic tumor immunology can lead to the development of new immunotherapeutic strategies.

Antibody-suppressor CXCR5+ CD8+ T cellular therapy ameliorates antibody-mediated rejection following kidney transplant in CCR5 KO mice.

CCR5 KO kidney transplant (KTx) recipients are extraordinarily high alloantibody producers and develop pathology that mimics human antibody-mediated rejection (AMR). C57BL/6 and CCR5 KO mice (H-2b ) were transplanted with A/J kidneys (H-2a ); select cohorts received adoptive cell therapy (ACT) with alloprimed CXCR5+ CD8+ T cells (or control cells) on day 5 after KTx. ACT efficacy was evaluated by measuring posttransplant alloantibody, pathology, and allograft survival. Recipients were assessed for the quantity of CXCR5+ CD8+ T cells and CD8-mediated cytotoxicity to alloprimed IgG+ B cells. Alloantibody titer in CCR5 KO recipients was four-fold higher than in C57BL/6 recipients. The proportion of alloprimed CXCR5+ CD8+ T cells 7 days after KTx in peripheral blood, lymph node, and spleen was substantially lower in CCR5 KO compared to C57BL/6 recipients. In vivo cytotoxicity towards alloprimed IgG+ B cells was also reduced six-fold in CCR5 KO recipients. ACT with alloprimed CXCR5+ CD8+ T cells (but not alloprimed CXCR5- CD8+ or third-party primed CXCR5+ CD8+ T cells) substantially reduced alloantibody titer, ameliorated AMR pathology, and prolonged allograft survival. These results indicate that a deficiency in quantity and function of alloprimed CXCR5+ CD8+ T cells contributes to high alloantibody and AMR in CCR5 KO recipient mice, which can be rescued with ACT.

Invariant NKT Cells Promote the Development of Highly Cytotoxic Multipotent CXCR3+CCR4+CD8+ T Cells That Mediate Rapid Hepatocyte Allograft Rejection.

Hepatocyte transplant represents a treatment for metabolic disorders but is limited by immunogenicity. Our prior work identified the critical role of CD8+ T cells, with or without CD4+ T cell help, in mediating hepatocyte rejection. In this study, we evaluated the influence of invariant NKT (iNKT) cells, uniquely abundant in the liver, upon CD8-mediated immune responses in the presence and absence of CD4+ T cells. To investigate this, C57BL/6 (wild-type) and iNKT-deficient Jα18 knockout mice (cohorts CD4 depleted) were transplanted with allogeneic hepatocytes. Recipients were evaluated for alloprimed CD8+ T cell subset composition, allocytotoxicity, and hepatocyte rejection. We found that CD8-mediated allocytotoxicity was significantly decreased in iNKT-deficient recipients and was restored by adoptive transfer of iNKT cells. In the absence of both iNKT cells and CD4+ T cells, CD8-mediated allocytotoxicity and hepatocyte rejection was abrogated. iNKT cells enhance the proportion of a novel subset of multipotent, alloprimed CXCR3+CCR4+CD8+ cytolytic T cells that develop after hepatocyte transplant and are abundant in the liver. Alloprimed CXCR3+CCR4+CD8+ T cells express cytotoxic effector molecules (perforin/granzyme and Fas ligand) and are distinguished from alloprimed CXCR3+CCR4-CD8+ T cells by a higher proportion of cells expressing TNF-α and IFN-γ. Furthermore, alloprimed CXCR3+CCR4+CD8+ T cells mediate higher allocytotoxicity and more rapid allograft rejection. Our data demonstrate the important role of iNKT cells in promoting the development of highly cytotoxic, multipotent CXCR3+CCR4+CD8+ T cells that mediate rapid rejection of allogeneic hepatocytes engrafted in the liver. Targeting iNKT cells may be an efficacious therapy to prevent rejection of intrahepatic cellular transplants.

A Case of COVID-19 Induced Thrombotic Thrombocytopenic Purpura.

Thrombotic Thrombocytopenic Purpura (TTP) is a challenging thrombotic diathesis which requires prompt diagnosis and therapeutic intervention in order to avoid life-threatening consequences. There are two forms of TTP, congenital and acquired, with the acquired form constituting about 90% of cases. Both forms are associated with a deficiency of ADAMTS-13, a metalloproteinase enzyme responsible for cleaving ultra-large von Willebrand factor (uLvWF), preventing its pathologic accumulation. Within the last year, many of the diverse and serious effects of the COVID-19 virus have come to recognition, with some of the most dire consequences involving devastating vascular and hematologic complications. As with many viruses, it seems that the endothelium and the vasculature are often prime targets. Here, we report a case of a 30 year old male who was diagnosed with TTP approximately one week after a positive COVID-19 test result. He responded appropriately to plasma exchange (PLEX), caplacizumab, and steroids. We believe it is important to investigate a potential link between these two conditions, as TTP has significant morbidity and mortality risk if left unattended. We hope that our report will contribute to a better understanding of this potential link.

Disparities in ovarian cancer treatment and overall survival according to race: An update.

OBJECTIVE: To determine whether guideline non-adherence is associated with Black race. METHODS: A retrospective review of National Cancer Database records of women diagnosed with epithelial ovarian cancer from 2012 to 2016 who identified as "White" or "Black" was performed. Exposure was adherence or non-adherence to National Comprehensive Cancer Network guidelines for treatment. Outcomes were differences in disease characteristics and overall survival in months. RESULTS: Of the 29,948 eligible patients, 93% (n = 27,744) were White and 7% (n = 2204) were Black. Having stage IV disease (OR 1.45, 95% CI 1.23-1.70; P < 0.001) and treatment in a comprehensive (OR 1.58, 95% CI 1.16-2.15; P = 0.0039) or academic (OR 2.30, 95% CI 1.70-3.12; P < 0.001) treatment facility were associated with Black race. Adherence to guidelines did not predict Black race (OR for adherence 1.0021, 95% CI 0.89-1.13; P = 0.97). Median survival for White patients with adherent care was 63.4 months and 51.4 months for Black patients (P = 0.0001). Median survival for White patients with non-adherent care was 60.5 months and 47.2 months for Black patients (P < 0.0001). Median overall survival was 61.1 months in White patients and 49.3 months in Black patients (P < 0.0001). CONCLUSIONS: Our data suggest that while Black patients and patients who receive non-NCCN guideline directed care have worse survival outcomes, guideline adherence is not independently associated with Black race. We must consider other socioeconomic, environmental and system factors that are contributing to the survival discrepancy in Black patients with ovarian cancer.

Idiopathic Purulent Pericarditis Caused by Methicillin-Sensitive Staphylococcus Aureus in an Immunocompetent Adult.

INTRODUCTION: Acute purulent pericarditis is an exceedingly rare entity most often caused by direct intrathoracic contamination or hematogenous spread of a bacterial infection. Mortality nears 100% when left untreated. We present here a rare case of idiopathic bacterial pericarditis caused by methicillin-sensitive Staphylococcus aureus (MSSA). CASE: A 69-year-old male presented with chest pain and abdominal pain. He was found to have a pericardial effusion and tamponade and underwent emergent pericardiocentesis. Pericardial fluid culture grew methicillin-sensitive Staphylococcus aureus. The patient required multiple pericardial washouts and was then treated with four weeks of intravenous antibiotics. CONCLUSION: While uncommon, clinical suspicion for purulent pericarditis should remain high due to the associated high mortality.

Cutaneous Lesion of the Nose as Initial Presentation of Esophageal Adenocarcinoma.

BACKGROUND/AIM: Cutaneous manifestations of disease are exceedingly rare and commonly overlooked in clinical practice. Allergies or contact dermatitis, autoimmune disease or skin cancer are the most common conditions typically associated with skin lesions. Rarely, cutaneous lesions may be the first sign of internal malignancy, or even resemble recurrent disease in those with history of cancer. CASE REPORT: Herein, we report a case of an otherwise healthy male who presented to his primary care provider (PCP) with a skin lesion misdiagnosed as a furuncle, which eventually led to diagnosis of metastatic esophageal cancer. The patient was a 64-year-old male, presenting with a fungating lesion on the tip of his nose which was biopsied, confirming adenocarcinoma likely from a gastrointestinal source. Staging imaging showed extensive lung, liver, and boney metastatic disease. He was initially treated with chemotherapy and trastuzumab. CONCLUSION: Cutaneous lesions are a rare presenting sign of malignancy, but rapidly growing lesions should be evaluated for possible metastatic disease.

Stepwise pathogenic evolution of Mycobacterium abscessus.

Although almost all mycobacterial species are saprophytic environmental organisms, a few, such as Mycobacterium tuberculosis, have evolved to cause transmissible human infection. By analyzing the recent emergence and spread of the environmental organism M. abscessus through the global cystic fibrosis population, we have defined key, generalizable steps involved in the pathogenic evolution of mycobacteria. We show that epigenetic modifiers, acquired through horizontal gene transfer, cause saltational increases in the pathogenic potential of specific environmental clones. Allopatric parallel evolution during chronic lung infection then promotes rapid increases in virulence through mutations in a discrete gene network; these mutations enhance growth within macrophages but impair fomite survival. As a consequence, we observe constrained pathogenic evolution while person-to-person transmission remains indirect, but postulate accelerated pathogenic adaptation once direct transmission is possible, as observed for M. tuberculosis Our findings indicate how key interventions, such as early treatment and cross-infection control, might restrict the spread of existing mycobacterial pathogens and prevent new, emergent ones.

Hyperhemolysis Syndrome in a Patient With Sickle Cell Disease and Acute Chest Syndrome.

Sickle cell anemia patients often present to the hospital with acute vaso-occlusive pain crisis. Symptoms can include, but are not limited to, chest pain, abdominal pain, and musculoskeletal pain. These symptoms are brought about due to the pathology of the disease. Abnormal hemoglobin S causes red blood cells to band together, otherwise known as "sickling." These patients also often present with very low hemoglobin levels on initial evaluation. In most cases, packed red blood cell transfusions are needed in order to replenish these patient's functional hemoglobin supply. Unfortunately, transfusing sickle cell patients can lead to an unwanted consequence, that of hyperhemolysis syndrome, in which blood transfusions prompt further hemolysis of the already sickled red blood cells. When this complication arises, caution must be exercised in deciding the next steps of treatment.

Herpes zoster during arsenic trioxide therapy for acute promyelocytic leukemia.

Historically, arsenic exposure has been associated with herpes zoster (HZ) infection, however the risk is not well characterized in arsenic trioxide (ATO) treated patients with acute promyelocytic leukemia (APL). We aimed to characterize the risk of HZ in 112 ATO treated patients with APL with and without antiviral prophylaxis (AVP). HZ occurred in 13/112 (11.6%) within 6 months of completing ATO, including one case of HZ encephalitis. AVP reduced the incidence of HZ (17.5% vs. 4.1%, RR 0.24 [95% CI 0.05-1.0, p = .025]) with a number needed to treat of 7.7. HZ despite AVP occurred later than HZ in patients without AVP (7.8 vs. 2.3 months from starting ATO, p = .11). Older age and prior HZ increased the risk of HZ in patients not receiving AVP. Routine AVP should be considered in patients with APL receiving ATO, particularly in older patients and those with a history of HZ.

Nanoluciferase Reporter Mycobacteriophage for Sensitive and Rapid Detection of Mycobacterium tuberculosis Drug Susceptibility.

Phenotypic testing for drug susceptibility of Mycobacterium tuberculosis is critical to basic research and managing the evolving problem of antimicrobial resistance in tuberculosis management, but it remains a specialized technique to which access is severely limited. Here, we report on the development and validation of an improved phage-mediated detection system for M. tuberculosis We incorporated a nanoluciferase (Nluc) reporter gene cassette into the TM4 mycobacteriophage genome to create phage TM4-nluc. We assessed the performance of this reporter phage in the context of cellular limit of detection and drug susceptibility testing using multiple biosafety level 2 drug-sensitive and -resistant auxotrophs as well as virulent M. tuberculosis strains. For both limit of detection and drug susceptibility testing, we developed a standardized method consisting of a 96-hour cell preculture followed by a 72-hour experimental window for M. tuberculosis detection with or without antibiotic exposure. The cellular limit of detection of M. tuberculosis in a 96-well plate batch culture was ≤102 CFU. Consistent with other phenotypic methods for drug susceptibility testing, we found TM4-nluc to be compatible with antibiotics representing multiple classes and mechanisms of action, including inhibition of core central dogma functions, cell wall homeostasis, metabolic inhibitors, compounds currently in clinical trials (SQ109 and Q203), and susceptibility testing for bedaquiline, pretomanid, and linezolid (components of the BPaL regimen for the treatment of multi- and extensively drug-resistant tuberculosis). Using the same method, we accurately identified rifampin-resistant and multidrug-resistant M. tuberculosis strains.IMPORTANCEMycobacterium tuberculosis, the causative agent of tuberculosis disease, remains a public health crisis on a global scale, and development of new interventions and identification of drug resistance are pillars in the World Health Organization End TB Strategy. Leveraging the tractability of the TM4 mycobacteriophage and the sensitivity of the nanoluciferase reporter enzyme, the present work describes an evolution of phage-mediated detection and drug susceptibility testing of M. tuberculosis, adding a valuable tool in drug discovery and basic biology research. With additional validation, this system may play a role as a quantitative phenotypic reference method and complement to genotypic methods for diagnosis and antibiotic susceptibility testing.

A highly stable blood meal alternative for rearing Aedes and Anopheles mosquitoes.

We investigated alternatives to whole blood for blood feeding of mosquitoes with a focus on improved stability and compatibility with mass rearing programs. In contrast to whole blood, an artificial blood diet of ATP-supplemented plasma was effective in maintaining mosquito populations and was compatible with storage for extended periods refrigerated, frozen, and as a lyophilized powder. The plasma ATP diet supported rearing of both Anopheles and Aedes mosquitoes. It was also effective in rearing Wolbachia-infected Aedes mosquitoes, suggesting compatibility with vector control efforts.

Melanoma patient derived xenografts acquire distinct Vemurafenib resistance mechanisms.

Variable clinical responses, tumor heterogeneity, and drug resistance reduce long-term survival outcomes for metastatic melanoma patients. To guide and accelerate drug development, we characterized tumor responses for five melanoma patient derived xenograft models treated with Vemurafenib. Three BRAF(V600E) models showed acquired drug resistance, one BRAF(V600E) model had a complete and durable response, and a BRAF(V600V) model was expectedly unresponsive. In progressing tumors, a variety of resistance mechanisms to BRAF inhibition were uncovered, including mutant BRAF alternative splicing, NRAS mutation, COT (MAP3K8) overexpression, and increased mutant BRAF gene amplification and copy number. The resistance mechanisms among the patient derived xenograft models were similar to the resistance pathways identified in clinical specimens from patients progressing on BRAF inhibitor therapy. In addition, there was both inter- and intra-patient heterogeneity in resistance mechanisms, accompanied by heterogeneous pERK expression immunostaining profiles. MEK monotherapy of Vemurafenib-resistant tumors caused toxicity and acquired drug resistance. However, tumors were eradicated when Vemurafenib was combined the MEK inhibitor. The diversity of drug responses among the xenograft models; the distinct mechanisms of resistance; and the ability to overcome resistance by the addition of a MEK inhibitor provide a scheduling rationale for clinical trials of next-generation drug combinations.

Ancient homology underlies adaptive mimetic diversity across butterflies.

Convergent evolution provides a rare, natural experiment with which to test the predictability of adaptation at the molecular level. Little is known about the molecular basis of convergence over macro-evolutionary timescales. Here we use a combination of positional cloning, population genomic resequencing, association mapping and developmental data to demonstrate that positionally orthologous nucleotide variants in the upstream region of the same gene, WntA, are responsible for parallel mimetic variation in two butterfly lineages that diverged >65 million years ago. Furthermore, characterization of spatial patterns of WntA expression during development suggests that alternative regulatory mechanisms underlie wing pattern variation in each system. Taken together, our results reveal a strikingly predictable molecular basis for phenotypic convergence over deep evolutionary time.

Augmenting protein release from layer-by-layer functionalized agarose hydrogels.

Recent work demonstrated the efficacy of combining layer-by-layer assembly with hydrogels to provide the controlled delivery of proteins for use in nerve repair scaffolds. In this work, we augmented the protein dose response by controlling and increasing the hydrogel internal surface area. Sucrose was added to agarose during gelation to homogenize the nanopore morphology, resulting in increased surface area per unit volume of hydrogel. The surface area of a range of compositions (1.5-5.0 wt% agarose and 0, 50 and 65 wt% sucrose) was measured. Gels were supercritically dried to preserve porosity enabling detailed pore morphology measurements using nitrogen adsorption and high resolution scanning electron microscopy. The resulting surface area, normalized by superficial gel volume, ranged between 6m(2)/cm(3)gel and 56 m(2)/cm(3)gel. Using the layer-by-layer process to load lysozyme, a neurotrophic factor analog, a relationship was observed between surface area and cumulative dose response ranging from 176 to 2556 µg/mL, which is in the range of clinical relevance for the delivery of growth factors. In this work, we demonstrated that the ability to control porosity is key in tuning drug delivery dose response from layer-by-layer modified hydrogels.

Melanoma genotypes and phenotypes get personal.

Traditionally, the diagnosis of metastatic melanoma was terminal to most patients. However, the advancements towards understanding the fundamental etiology, pathophysiology, and treatment have raised melanoma to the forefront of contemporary medicine. Indeed, the evidence of durable remissions are being heard ever more frequently in clinics around the globe. Despite having more gene mutations per cell than any other type of cancer, investigators are overcoming complex genomic landscapes, signaling pathways, and immune checkpoints by generating novel technological methods and clinical protocols with breath-taking speed. Significant progress in deciphering molecular genetics, epigenetics, kinase-driven networks, metabolomics, and immune-enhancing pathways to achieve personalized and positive outcomes has truly provided new hope for melanoma patients. However, obstacles requiring breakthroughs include understanding the influence of sunlight exposure on melanoma etiology, and overcoming all too frequently acquired drug resistance, complicating targeted therapy. Pathologists continue to have critically important roles in advancing the field, particularly in the area of transitioning from microscope-based diagnostic reports to pharmacogenomics through molecularly informed tumor boards. Although melanoma is no longer considered just 'one disease', pathologists will continue this rapidly progressing and exciting journey to identify tumor subtypes, to utilize tumorgraft or so-called patient-derived xenograft (PDX) models, and to develop companion diagnostics to keep pace with the bewildering breakthroughs occurring on a regular basis. Exactly which combination of drugs will ultimately be required to eradicate melanoma cells remains to be determined. However, it is clear that pathologists who are as dedicated to melanoma as the pioneering pathologist Dr Sidney Farber was committed to childhood cancers, will be required as the battle against melanoma continues. In this review, we describe what sets melanoma apart from other tumors, and demonstrate how lessons learned in the melanoma clinic are being transferred to many other types of aggressive neoplasms.