Figure 1. Macroscopic, microscopic, and immunophenotypic findings of the case: (A) Multiple purple skin nodules on the back of his left shoulder; (B) the ill-defined mass had a solid and tan-white cut surface and was firm in consistency with visible infiltration of subcutaneous tissue; (C) H&E staining shows diffuse infiltration of the tumor cells in the dermis and subcutis (4 x); immunophenoty...

Blastic plasmacytoid dendritic cell neoplasm (a.k.a. NK cell lymphoma, CD4+CD56+ haematodermic neoplasm) is a rare aggressive tumour that arises from plasmacytoid dendritic cell precursors. We report the first case from Malaysia of a 79-year-old Chinese woman who presented with purpuric plaques and nodules produced by pleomorphic CD4+, CD56+, CD68+, CD123+ and CD303+, but CD2APmononuclear cell ...

A retrospective analysis of 173 skin biopsy specimens of myeloid leukemia cutis (MLC) was performed to determine histologic and immunophenotypic criteria that could distinguish the varied myeloid disorders from one another. For the study, 11 relevant histologic items were scored and 12 antigens were studied (CD68 [KP1], CD163, CD14, CD4, myeloperoxidase [MPO], CD33, CD117, CD34, CD56, MIB-1, CD...

Atopic dermatitis (AD) is a pruritic, chronically relapsing skin disease in which Th2 cells play a crucial role in cutaneous and extracutaneous immune reactions. In humans, CD11c+CD123- myeloid dendritic cells (mDC) and CD11c-CD123+ plasmacytoid DC (pDC) orchestrate the decision-making process in innate and acquired immunity. Since the number and function of these blood dendritic cell (DC) subs...

The treatment of patients with acute myeloid leukemia (AML) with targeted immunotherapy is challenged by the heterogeneity of the disease and a lack of tumor-exclusive antigens. Conventional immunotherapy targets for AML such as CD33 and CD123 have been proposed as targets for chimeric antigen receptor (CAR)-engineered T-cells (CAR-T-cells), a therapy that has been highly successful in the trea...

Blastic plasmacytoid dendritic cell neoplasm is a rare clinicopathologic entity, characterized by strong skin tropism and a poor prognosis. The diagnosis is generally made by skin biopsy with appropriate immunohistochemical studies. To identify potential biological prognostic factors for blastic plasmacytoid dendritic cell neoplasm, we performed an extended clinico-immunohistochemical study on ...

A 64-year-old man presented with progressive skin lesions, which were diagnosed as blastic plasmacytoid dendritic cell neoplasm (BPDCN) and were confirmed with marrow involvement. He received SL-401 chemotherapy but developed persistent monocytosis. A 3-month follow-up bone marrow biopsy showed characteristic “tadpole” cells on smears (panels A-B; original magnifications 3500, hematoxylin and e...

Complications of allogeneic hematopoietic stem cell transplantation (HSCT) have been attributed to immune cells transferred into the patient with the graft. However, a detailed immune cell composition of the graft is usually not evaluated. In the present study, we determined the level of variation in the composition of immune cells between clinical HSCT grafts and whether this variation is asso...

Myeloid leukemia cutis (LC) and blastic plasmacytoid dendritic cell neoplasm (BPDCN) are morphologically indistinguishable malignancies that frequently manifest in the skin. Separating myeloperoxidase-negative LC from BPDCN may be particularly challenging. We identified a panel of immunohistochemical stains to distinguish myeloid LC (23 cases) from BPDCN (12 cases): myeloperoxidase, which stain...

CSL362 is a humanized interleukin-3 (IL-3)-neutralizing monoclonal antibody with enhanced effector function that binds the α subunit of the IL-3 receptor (IL3Rα). The crystal structure of an IL3Rα:CSL362 complex shows that IL3Rα adopts "open" and "closed" conformations. CSL362 blocks IL-3 function through both IL3Rα conformations but via distinct and unexpected mechanisms.