Hodgkin lymphoma is a unique malignancy in which reactive immune cells vastly outnumber the tumor cells. The microenvironment is essential in many different aspects of Hodgkin lymphoma biology and has ramifications for diagnosis, clinical presentation, and therapeutic options. In this chapter we review current knowledge on the Hodgkin lymphoma microenvironment. Its composition is highly variable and provides the basis for diagnostic subtyping. T cells are virtually always present and usually cluster together with the tumor cells in so-called rosettes. We describe mechanisms by which the tumor cells actively...

Hodgkin lymphoma is a B cell derived malignancy characterized by a low number of tumor cells within an environment consisting of inflammatory cells. Recently, immune checkpoint blockade targeting the PD-1-PD-L1 axis has shown to be a great success in relapsed and refractory Hodgkin lymphoma patients. However, complete responses are scarce and median progression-free survival is limited to around 11-15 months. Efficiency of PD-1 blockade in HL might be dependent on CD4 + T cells, but also tumor associated macrophages (TAMs) and NK cells are implicated. The aim of...

OBJECTIVES: MYC gene rearrangements in diffuse large B cell lymphomas (DLBCLs) result in high proliferation rates and are associated with a poor prognosis. Strong proliferation is associated with high metabolic demand and tumour necrosis. The aim of this study was to investigate differences in the presence of necrosis and semiquantitative 18F-FDG PET metrics between DLBCL cases with or without a MYC rearrangement. The prognostic impact of necrosis and semiquantitative 18F-FDG PET parameters was investigated in an explorative survival analysis. METHODS: Fluorescence in situ hybridisation analysis for MYC rearrangements,...

BACKGROUND: ABO-incompatible and ABO-compatible kidney transplantation are equivalent in terms of short-term graft and patient survival. This is thought to be the result of ABO-incompatible graft accommodation, which occurs when anti-blood group antibodies re-occur after transplantation but somehow do not yield their detrimental effect. The underlying mechanism is unclear, but one of the hypotheses is that this is the result of complement inhibition. Since virtually all ABO-incompatible graft biopsies are C4d positive, this complement inhibition must occur somewhere in the complement cascade after the formation of C4d has...

Background: Granulomatosis with polyangiitis (GPA) patients are prone to disease relapses. We aimed to determine whether GPA patients at risk for relapse can be identified by differences in B cell subset frequencies. Methods: Eighty-five GPA patients were monitored for a median period of 3.1 years (range: 0.1-6.3). Circulating B cell subset frequencies were analyzed by flow cytometry determining the expression of CD19, CD38, and CD27. B cell subset frequencies at the time of inclusion of future-relapsing (F-R) and non-relapsing (N-R) patients were compared and related to relapse-free survival....