B-cell differentiation immunophenotypes in classical Hodgkin lymphomas

The bcl6/CD10/MUM1/CD138 B-cell differentiation immunophenotypes were analysed in 101 cases of classical Hodgkin lymphomas (cHL) aiming to elucidate their histogenesis. Three major bcl6/CD10/MUM1/CD138 immunophenotypes were distinguished on the basis of the immunohistochemical positivity of Hodgkin and Reed-Sternberg (H/RS) cells: (a) the late germinal center (GC)/early post-GC B-cell-like immunophenotype (bcl6-/CD10-/MUM1+/CD138-); 59/101 cases (59%), (b) the post-GC B-cell-like immunophenotype (bcl6-/CD10-/MUM1+/CD138+); 24/101 cases (24%) and (c) the indeterminate immunophenotype (bcl6+/CD10-/MUM1+/CD138-: 14 cases and bcl6+/CD10-/MUM1+/CD138+: four cases); 18/101 cases (18%). The above findings indicate that H/RS cells in most cHL display bcl6/CD10/MUM1/CD138 immunophenotypes consistent with late GC/early post-GC or post-GC B-cell differentiation. In addition, H/RS cells in a small fraction of cHL display indeterminate bcl6/CD10/MUM1/CD138 immunophenotypic profiles which are characterized by simultaneous expression of GC, late GC/early post-GC and post-GC B-cell differentiation proteins. These immunophenotypic profiles do not correspond to the differentiation immunophenotypes of normal B-cells and their identification in a part of cHL suggests that the differentiation process of H/RS cells is not complete in a fraction of these cells and/or is still ongoing at the time of observation.     

Retrospective study on poliomyelitis cases in northern Greece

Here we report the results of a retrospective study on the epidemiological characteristics and genetic relationships of the virus isolates responsible for the last poliomyelitis cases in Greece. The last wild poliomyelitis case in Greece was detected in 1996, and the last vaccine-related strain was isolated in 1998. The whole of Europe, including Greece, is now considered to be polio-free.     

Autoimmune manifestations in common variable immunodeficiency

Common variable immunodeficiency (CVID) is a disorder characterized by decreased serum immunoglobulin concentrations and increased incidence of recurrent infections. Interestingly 20–25% of patients with CVID develop clinical features suggestive of an autoimmune disease. Although this association is well established, the immunodeficiency background of CVID patients manifesting autoimmune disorders is often overlooked. This study describes three CVID patients displaying a variety of autoimmune manifestations. The pathophysiologic mechanisms of autoimmunity in CVID are also reviewed.     

A spatio-temporal simulation model of the response of solid tumours to radiotherapy in vivo: parametric validation concerning oxygen enhancement ratio and cell cycle duration

Advanced bio-simulation methods are expected to substantially improve radiotherapy treatment planning. To this end a novel spatio-temporal patient-specific simulation model of the in vivo response of malignant tumours to radiotherapy schemes has been recently developed by our group. This paper discusses recent improvements to the model: an optimized algorithm leading to conformal shrinkage of the tumour as a response to radiotherapy, the introduction of the oxygen enhancement ratio (OER), a realistic initial cell phase distribution and finally an advanced imaging-based algorithm simulating the neovascularization field. A parametric study of the influence of the cell cycle duration Tc, OER, OERbeta for the beta LQ parameter on tumour growth. shrinkage and response to irradiation under two different fractionation schemes has been made. The model has been applied to two glioblastoma multiforme (GBM) cases, one with wild type (wt) and another one with mutated (mt) p53 gene. Furthermore, the model has been applied to a hypothetical GBM tumour with alpha and beta values corresponding to those of generic radiosensitive tumours. According to the model predictions, a whole tumour with shorter Tc tends to repopulate faster, as is to be expected. Furthermore, a higher OER value for the dormant cells leads to a more radioresistant whole tumour. A small variation of the OERbeta value does not seem to play a major role in the tumour response. Accelerated fractionation proved to be superior to the standard scheme for the whole range of the OER values considered. Finally, the tumour with mt p53 was shown to be more radioresistant compared to the tumour with wt p53. Although all simulation predictions agree at least qualitatively with the clinical experience and literature, a long-term clinical adaptation and quantitative validation procedure is in progress.