T-cell receptor V beta-family usage in primary cutaneous and primary nodal T-cell non-Hodgkin's lymphomas.

To evaluate whether the expression of T-cell receptor (TCR) V beta families in eight cases of malignant T-cell lymphomas took place in a preferential manner, we analyzed four cases of mycosis fungoides (MF), the most common form of primary cutaneous T-cell non-Hodgkin's lymphomas (NHL), and four cases of primary nodal T-cell NHL. The usage of V beta families in T-cell populations was investigated on mRNA that was transcribed to cDNA using a C beta primer and reverse transcriptase. Subsequently, the specific usage of the families was analyzed by polymerase chain reaction (PCR) using combinations of the selected C beta-oligonucleotide primer and one of the family-specific V beta primers. Peripheral blood lymphocytes from four healthy volunteers and 1 "reactive" lymph node served as a control and expressed all 20 V beta families tested for. In T-cell lines, with restricted V beta expression, and in three patients with advanced MF, only one or two V beta families were expressed at the mRNA level. In an early MF lesion this monoclonal expression was absent: several V beta families were expressed with a weak intensity. This may indicate either a polyclonal origin of MF, or that too few monoclonal neoplastic cells were present in the tissue specimen. In the four nodal T-cell NHL, only one family could be clearly distinguished, whereas some of the other V beta families showed only a weak expression. These latter families represent the reactive T-cell component in the nodal T-cell NHL. Both in nodal T-cell NHL and in MF there was no preferential expression of a particular V beta family. There was a good correlation between PCR data and the expression of V beta-family protein products observed by immunohistochemistry on tissue sections of the T-cell lymphomas. All T-cell lines, three cases of MF, and three cases of nodal T-cell NHL showed a rearrangement of the TCR beta chain on DNA level.

Acute thymus involution during infancy and childhood: immunohistology of the thymus and peripheral lymphoid tissues after acute illness.

We previously reported that the histologic grade of accidental involution of the thymus in infancy and childhood after a short period of acute illness correlates strongly with the duration of illness (Van Baarlen et al., Hum Pathol 1988;19:1155-60). We now extend this finding by reporting the phenotypic expression of thymus lymphoid and stromal cells. The thymic findings were correlated with changes in peripheral lymphoid organs. In the involuted thymus the immature and proliferating lymphoid populations that are present in the normal (uninvoluted) cortex were completely absent but the cortical epithelial network remained essentially intact even with increasing histologic grades of involution. Cells expressing the phenotype of subcapsular and medullary epithelium were found in this cortical stroma. In the subcapsular area, loss of expression of thymosin components alpha 1 and beta 4 was observed, without loss of epithelial cells. In the medulla a loss of cells expressing HLA-DR was observed, probably reflecting a loss of interdigitating cells. There was no correlation between changes in the thymus and peripheral lymphoid organs.

A causal typology of migration: the role of commuting.

"The article concentrates on migration typologies and the role they play in the analysis of residential and labour migration. It is argued that in order to be able to understand the decisions individuals make regarding migration, the spatial adjustments as a consequence of the spatial separation of residence and workplace should be investigated. One way of obtaining more insight about these adjustment processes is by analysis of the influence of actual and perceived commuting on the decision to move. The suggested typology of residential and labour migration therefore contains commuting as the key factor. As an empirical application of the concepts, an analysis of actual migration in the Netherlands was undertaken." (SUMMARY IN FRE AND GER)