Rabbit Anti-Human CD7 (internal) Polyclonal antibody

Natural killer (NK) cells are cytotoxic lymphocytes and play a vital role in controlling viral infections and cancer. In contrast to B and T lymphopoiesis where cellular and regulatory pathways have been extensively characterized, the cellular stages of early human NK cell commitment remain poorly understood. Here we demonstrate that a Lin(-)CD34(+) CD38(+)CD123(-)CD45RA(+)CD7(+)CD10(+)CD127(-) population represents a NK lineage-restricted progenitor (NKP) in fetal development, umbilical cord blood, and adult tissues. The newly identified NKP has robust NK cell potential both in vitro and in vivo, generates functionally cytotoxic NK cells, and lacks the ability to produce T cells, B cells, myeloid cells, and innate lymphoid-like cells (ILCs). Our findings identify an early step to human NK cell commitment and provide new insights into the human hematopoietic hierarchy.

Primary effusion lymphoma (PEL) is a rare B cell lymphoproliferative disorder that arises predominantly in body cavities causing malignant effusions. The incidence of PEL is very low, accounting for approximately 4% of all HIV-associated non-Hodgkin lymphomas. PEL has also been described in elderly patients and after solid-organ transplantation. It is associated in all cases with human herpes virus 8 (HHV8). We describe a case of PEL in a 88-year-old HIV-negative woman who presented with progressive dyspnea and moderate right-sided pleural effusion without significant lymphadenopathies or other effusions. The cytological study of the pleural fluid revealed a dense proliferation of large plasmablastic cells. A six-color multiparametric flow cytometry immunophenotyping study was carried out, and revealed 45% of large in size and high cellular complexity cells positive for CD45 (dim), CD38, CD138, CD30 and HLA-DR; and negative for CD19, CD20, cytoplasmatic CD79a, surface and cytoplasmic light chains Kappa and Lambda, CD3, CD4, CD5, CD7, CD8, CD28, CD56, CD81, and CD117. In situ hybridization for EBV-encoded smalI RNA was negative and immunohistochemistry for Kaposi sarcoma herpesvirus (HHV8) confirmed the diagnosis of PEL. Our results confirm that flow cytometry bring useful data in the diagnosis of large-cell lymphomas involving body cavities. (c) 2018 International Clinical Cytometry Society