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Purpose: Common variable immune deficiency (CVID) confers an increased risk of lymphoid neoplasms, but reports describing the precise WHO specification of the lymphoma subtypes and their immunological environment are lacking. We therefore classified lymphomas—occurring in a cohort of 21 adult CVID patients during a 17-year period at our center—according to the 2016 WHO classification and characterized the local and systemic immunological context Results: The median time between the onset of CVID and lymphoma was 14 years. Patients showed a high prevalence of preceding immune dysregulation: lymphadenopathy (n = 13, 62%), splenomegaly (n = 18, 86%), autoimmune cytopenia (n = 14, 67%), and gastrointestinal involvement (n = 15, 71%). The entities comprised extranodal marginal zone lymphoma (n = 6), diffuse large B cell lymphoma (n = 7), plasmablastic lymphoma (n = 1), classic Hodgkin lymphoma (n = 4, including three cases with germline CTLA4 mutations), T cell large granular lymphocytic leukemia (n = 2), and peripheral T cell lymphoma, not otherwise specified (n = 1), but no follicular lymphoma. An Epstein-Barr virus association was documented in eight of 16 investigated lymphomas. High expression of PDL1 by tumor cells in five and of PDL1 and PD1 by tumor-infiltrating macrophages and T cells in 12 of 12 investigated lymphomas suggested a tolerogenic immunological tumor environment. Conclusion: In summary, a diverse combination of specific factors like genetic background, chronic immune activation, viral trigger, and impaired immune surveillance contributes to the observed spectrum of lymphomas in CVID. In the future, targeted therapies, e.g., PD1/PDL1 inhibitors in CVID associated lymphomas with a tolerogenic environment may improve therapy outcome. [ABSTRACT FROM AUTHOR]

Abstract: Since myeloma cells express various potential target antigens, active immunotherapy is being investigated as a novel treatment modality for myeloma. Immunization against the clonal myeloma immunoglobulin (idiotype) elicits protective immunity in mouse models. Idiotype vaccination of myeloma patients can induce cellular immunity, albeit as yet without firm evidence for improved clinical outcome. Other tumour-associated antigens (including cancer/testis antigens) are expressed with various frequencies in myeloma. T cells with specificity for these antigens may exist in myeloma patients, and immunization trials with some of these antigens are ongoing. Future studies need to identify the best antigen, the optimal vaccine formulation and schedule, and the preferable clinical situation for vaccination with myeloma antigens. In addition, immunization of stem cell donors with myeloma antigens may improve the efficacy and outcome of allogeneic stem cell transplantation through transfer of idiotype-directed immunity to the patient, and has already shown promising clinical results. [Copyright &y& Elsevier]

Induction of tumor-antigen-specific T cells in active cancer immunotherapy is generally difficult due to the very low anti-tumoral precursor cytotoxic T cells. By improving tumor-antigen uptake and presentation by dendritic cells (DCs), this problem can be overcome. Focusing on MAGE-A3 protein, frequently expressed in many types of tumors, we analyzed different DC-uptake routes after additional coating the recombinant MAGE-A3 protein with either a specific monoclonal antibody or an immune complex formulation. Opsonization of the protein with antibody resulted in increased DC-uptake compared to the uncoated rhMAGE-A3 protein. This was partly due to Fcγ receptor-dependent internalization. However, unspecific antigen internalization via macropinocytosis also played a role. When analyzing DC-uptake of MAGE-A3 antigen expressed in multiple myeloma cell line U266, pretreatment with proteasome inhibitor bortezomib resulted in increased apoptosis compared to γ-irradiation. Bortezomib-mediated immunogenic apoptosis, characterized by elevated surface expression of hsp90, triggered higher phagocytosis of U266 cells by DCs involving specific DC-derived receptors. We further investigated the impact of antigen delivery on T-cell priming. Induction of CD8 T-cell response was favored by stimulating naïve T cells with either antibody-opsonized MAGE-A3 protein or with the bortezomib-pretreated U266 cells, indicating that receptor-mediated uptake favors cross-presentation of antigens. In contrast, CD4 T cells were preferentially induced after stimulation with the uncoated protein or protein in the immune complex, both antigen formulations were preferentially internalized by DCs via macropinocytosis. In summary, receptor-mediated DC-uptake mechanisms favored the induction of CD8 T cells, relevant for clinical anti-tumor response. [ABSTRACT FROM AUTHOR]

Background: The therapeutic value of donor lymphocyte infusions in patients who relapse with acute myeloid leukemia (AML) after allogeneic hematopoietic stem cell transplantation (HSCT) is limited by a low efficacy and the risk of graft-versus-host disease. We aimed at generating leukemia-reactive donor T cells for patients with AML. Methods: Peripheral blood mononuclear cells of the donor were stimulated with mature donor dendritic cells, pulsed with irradiated patient leukemic blasts (LB), or directly with cytokine-treated LB. After 3 weekly stimulations, donor cells were tested for anti-leukemic reactivity in an IFNγ Elispot. Results: In 5 of 6 donors, cells with reactivity against patient LB with low or absent reactivity against non-leukemic cells could be generated. T cell subset analyses in 2 donors indicated that specific anti-leukemic reactivity was mainly mediated by CD4+ T cells, which were also the predominant cell fraction in 4 of 6 donors. One leukemia-reactive donor T cell line was expanded with a recently developed system. One week of expansion resulted in a 10-fold increase in reactivity with sustained specificity of the resulting T cell line. Conclusions: Our results show the feasibility of the in vitro generation of leukemia-reactive donor lymphocytes, rendering this method a promising tool for post-HSCT immunotherapy. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Clinical images from musculoskeletal ultrasonography of a 42-year-old man with a 1-day history of pain and swelling of the wrists and ankles due to acute sarcoidosis (Lofgren’s Syndrome) are presented.