Evidence that platelets from transfusion-dependent ß-thalassemia patients induce T cell activation.

A hypercoagulable state leading to increased risk for thrombotic events represents one of the most common complications observed in transfusion-dependent ß-thalassemia (TDT) patients. TDT patients have increased frequencies of circulating activated platelets. However, there is no information so far if platelets from TDT patients can activate T cells. In the present study we showed that T cells treated with platelets from TDT patients showed significant increased surface expression of CD69 compared to the T cells treated with platelets from healthy individuals. Patients with splenectomy showed increased T cell activation compared to patients with intact spleen. No T cell activation was observed following incubation with plasma alone, nor with platelets from healthy subjects. The percentages of regulatory T cells (Tregs) were also examined. TDT patients showed statistically significant increased percentages of Tregs compared to healthy controls. Additionally, we observed a positive statistically significant correlation between the percentages of Tregs and the platelet-induced activated T cells in patients who were not treated with aspirin. TDT patients showed increased levels of sP-selectin, suPAR and GDF-15, molecules implicated in platelet activation. We show that platelets from TDT patients can activate T cells in vitro. This activation correlates with markers of platelet activation and increased numbers of Tregs, perhaps in an effort to eliminate immune dysregulation, conceivably secondary to platelet activation.

How to Make the Right Diagnosis in Neutropenia.

Isolated neutropenia without anemia or thrombocytopenia is a common clinical problem. The etiology of neutropenia may vary from transient bone marrow suppression, caused by self-limited viral illnesses, to previously undiagnosed congenital syndromes or serious systemic diseases. Consequently, determining the underlying cause of neutropenia and what treatment is required can be challenging. Acquired neutropenia is common and most of the times an etiologic factor can be found. Congenital neutropenia (CN) is rare, and we still have a lot to learn from mutational analysis as to the exact role of gene abnormalities in the pathogenesis of these complex diseases. This mini-review discusses a proposed approach to neutropenia in the adult patient.

Immune Checkpoint Inhibitor-Associated Scleroderma-Like Syndrome: A Report of a Pembrolizumab-Induced "Eosinophilic Fasciitis-Like" Case and a Review of the Literature.

Immune checkpoint inhibitors are a promising new therapeutic strategy in oncology that aims to eliminate cancer cells by enhancing patients' immune response against tumor antigens. Despite their beneficial effects, immune checkpoint inhibitors are also responsible for a plethora of autoimmune manifestations, known as immune-related adverse events. We present a case of eosinophilic fasciitis-like disorder in an 81-year-old patient treated with the programmed death cell protein 1 inhibitor pembrolizumab for non-small-cell lung cancer. The patient developed characteristic indurated skin lesions in his limbs after 1½ years of treatment with pembrolizumab and a typical "groove sign." Raynaud's syndrome was absent. A full-thickness biopsy confirmed the clinical diagnosis of an "EF-like" condition. Neither peripheral eosinophilia nor eosinophilic infiltrates in the skin biopsy were found. His symptoms improved after a 2.5-month CPI discontinuation and treatment with 16 mg of methylprednisolone slowly tapered to a dose of 4 mg. Eosinophilic fasciitis is a rare immune-related adverse event of CPI treatment; our literature search identified only 12 cases that fulfill the criteria of EF in patients receiving CPIs.