CD3×CD19 bispecific antibodies and CD28 costimulation for locoregional treatment of low-malignancy non-Hodgkin’s lymphoma

 In advance of using bispecific antibodies for the treatment of B cell lymphoma in humans, we analysed CD3×CD19 bispecific antibodies for their capacity to induce T cell activiation in cell suspensions from follicular lymphoma lymph nodes. Here, we demostrate that the lack of costimulatory molecules, such as members of the B7 family, on the tumour cells resulted in insufficient activation of autologous T lymphocytes. However, stimulation and proliferation of T cells could be induced by addition of monospecific CD28 antibodies. Moreover, we show that bispecific CD3×CD19 antibodies can protect severe combined immunodeficiency (SCID) mice from human Epstein-Barr-virus (EBV)-induced B cell lymphoma growth. In these in vivo studies, CD28 costimulation did not show a significant benefit, possibly because of the high-level expression of CD80 and CD86 on the surface of the lymphoma cells. Furthermore, the treatment of SCID mice with bispecific antibodies, with or without CD28 antibodies, induced tumour-protective effects, as determined by a rechallenging experiment in long-term-surviving animals with the autologous EBV-transformed tumour B cell line. Treatment of a follicular lymphoma patient by intratumoural injection of both antibodies resulted in immunological responses with increases in the T/B ratio of peripheral blood as well as enhanced NK cell activity without toxic systemic side-effects. Accepted: 14 October 1997     

Immunologic status in Hodgkin patients: correlation with Epstein-Barr virus titers]

1. In Hodgkin's disease patient's immunological in vitro and in vivo parameters are of prognostic importance. 2. Skin test reactivity correlates to peripheral T-lymphocyte counts and Con A induced lymphoblastogenesis. 3. Con A is the most sensitive in vitro indicator for detecting latent immunodeficiency. 4. Hodgkin patients in long term remission after tumor reductive therapy exhibit a qualitative and quantitative lymphocyte defect. 5. In Hodgkin patients Herpes virus related antibody titers are elevated against Epstein Barr virus (EBV). The elevation coincides with a decreased T-cell number and function. Antibodies against other Herpes viruses (HSV, CMV, VZV) are in the normal range, when tested by the complement fixation method.