Age-related changes in the morphology and immunophenotype of spontaneous lymphomas of SJL/N mice

Comparison of Theiler's Murine Encephalomyelitis Virus Induced Spinal Cord and Peripheral Nerve Lesions Following Intracerebral and Intraspinal Infection

Hallmarks of Theiler's murine encephalomyelitis virus (TMEV)-induced demyelinating disease (TMEV-IDD) include spinal cord (SC) inflammation, demyelination and axonal damage occurring approximately 5-8 weeks after classical intracerebral (i.c.) infection. The aim of this study was to elucidate the consequences of intraspinal (i.s.) TMEV infection and a direct comparison of classical i.c. and intraspinal infection. Swiss Jim Lambert (SJL)-mice were i.s. infected with the BeAn strain of TMEV. Clinical investigations including a scoring system and rotarod analysis were performed on a regular basis. Necropsies were performed at 3, 7, 14, 28 and 63 days post infection (dpi) following i.s. and at 4, 7, 14, 28, 56, 98, 147 and 196 dpi following i.c. infection. Serial sections of formalin-fixed, paraffin-embedded SC and peripheral nerves (PN) were investigated using hematoxylin and eosin (HE) and immunohistochemistry. I.s. infected mice developed clinical signs and a deterioration of motor coordination approximately 12 weeks earlier than i.c. infected animals. SC inflammation, demyelination and axonal damage occurred approximately 6 weeks earlier in i.s. infected animals. Interestingly, i.s. infected mice developed PN lesions, characterized by vacuolation, inflammation, demyelination and axonal damage, which was not seen following i.c. infection. The i.s. infection model offers the advantage of a significantly earlier onset of clinical signs, inflammatory and demyelinating SC lesions and additionally enables the investigation of virus-mediated PN lesions.

MHC class I family proteins retard systemic lupus erythematosus autoimmunity and B cell lymphomagenesis

Dysregulation of the T cell-dependent Ab response can lead to numerous immunological disorders, ranging from systemic lupus erythematosus to B cell lymphomas. Cellular processes governed by MHC class II proteins play a major role in this response and its dysregulation. The extent to which processes controlled by the diverse family of MHC class I proteins impact such autoimmune and neoplastic disorders, however, is less clear. In this study, we genetically dissect the contributions of individual MHC class I family members and the pathological processes under their control in the systemic lupus erythematosus-like disease of BXSB.Yaa mice and B cell lymphomagenesis of SJL mice. This study reveals a powerful repressive regulatory axis comprised of MHC class I-dependent CD8(+) T cells and NK cells. These results indicate that the predominant role of the MHC class I protein family in such immunological disorders is to protect from more aggressive diseases.

Non-Hodgkin's lymphoma in the elderly. A study of 602 patients aged 70 or older from a Danish population-based registry. The Danish LYEO-Study Group

Within a 7-year period 1,597 newly diagnosed cases of non-Hodgkin's lymphoma (NHL) were included in a Danish population-based NHL registry. Of these, 602 (38%) were aged 70 years or older (age range 70-94, median: 76.8). They represent the population defined as 'elderly' patients in the present study. The average annual incidence rate for this elderly patient population was 35.7/10(5), as compared with 6.6/10(5) for patients aged less than 70 (overall annual incidence: 9.5/10(5)). Localised cases (stage I and II) and extranodal manifestations were found more frequently among elderly patients. The most common sites of extranodal involvement were the stomach (21% of all extranodal cases) and the bone marrow (16%). Histologically, follicular centroblastic/centrocytic cases were found to be less frequent (p less than 0.01) in elderly patients as compared to their younger counterparts (less than 70 years), who in contrast had a lower occurrence of diffuse centroblastic cases (p less than 0.01). Overall 7-year survival for the elderly patient population was 35% (median 1.7 years), and for patients aged less than 70 it was 57%. This difference persisted after correction for apparently NHL-unrelated deaths (52% vs. 66%, respectively, p less than 0.0001). Elderly patients with poor prognosis were characterised by the following features identified in a Cox-regression model: hepatic involvement, presence of B-symptoms, high-grade histology and elevated s-LDH. The corresponding relative risk values were in the order 2.4, 2.2, 1.9 and 1.6.

An immunohistochemical study of spontaneous lymphomas in the C57B1/10J mouse

Immunocytochemistry was used to examine 26 cases of composite lymphoma in the mouse mesenteric lymph node. The diagnosis was made by light microscopic criteria. A selection of polyclonal antibodies to light (Kappa and Lambda) and heavy chain (IgD, IgM, IgC, IgA, IgE) antigens was used together with three monoclonal antibodies to T cells, B cells (HLA-DR) and macrophages. Twenty lymphomas were classified as B cell and six as T cell. The B cells were subdivided into IgM and IgD (five), IgD (five), IgM (three) and IgA (one), three undifferentiated and, in three, there was insufficient tissue for further typing. There did not appear to be any correlation between the morphological appearance and the immunophenotype.