Differences in dexamethasone-sensitivity between lymphocytes from patients with Alzheimer's disease and patients with multi-infarct dementia

Peripheral blood mononuclear cells (PBMC) from 40 consecutive patients entering a screening program on cognitive impairment were studied in vitro with respect to their sensitivity to dexamethasone (DEX). Phytohemagglutinin-induced proliferation by PBMC from patients with senile dementia of the Alzheimer type (SDAT) was less sensitive to the...

Direct assessment of junctional diversity in rearranged T cell receptor β chain encoding genes by combined heteroduplex and single strand conformation polymorphism (SSCP) analysis

In order to define the extent of T cell heterogeneity and clonality, unique DNA sequences in the junctional region in rearranged T cell receptor (TcR) genes can be studied. For this purpose we have adapted a non-denaturing nucleic acid gel electrophoresis procedure to detect TcR junctional diversity. Detection of junctional diversity is based...

Changes in the intestinal lymphoid compartment through life: Implications for the local generation of intestinal T cells

Denaturing and non-denaturing gel electrophoresis as methods for the detection ofjunctional diversity in rearranged T cell receptor sequences

Two nucleic acid gel electrophoresis techniques were tested as a possible tool for analyzing junctional diversity in rearranged T cell receptor (TcR) sequences in order to define the extent of T cell heterogeneity. For this purpose denaturing gradient gel electrophoresis (DGGE) as well as non-denaturing gel electrophoresis (nDGE) techniques have...

Veroudering en het immuunsysteem

Decreased sensitivity to dexamethasone in lymphocytes from patients with Alzheimer's disease

Cortisol levels in patients with Alzheimer's disease (AD) are relatively unaffected by a challenge with dexamethasone (DEX) in vivo. The present study demonstrates that DEX is less inhibitory for phytohemagglutinin (PHA)-induced T cell proliferation in AD patients as compared to age-matched controls. Since no significant differences were found...

Identification of two moieties of ß-endorphin with opposing effects on rat T-cell proliferation

In a previous study we demonstrated that beta-endorphin (beta-end) may stimulate rat T-cell proliferation via triggering of non-opioid receptors, whereas this stimulatory effect is abrogated by interaction of beta-end with opioid receptors. In the present study we provide evidence for this dualistic nature of beta-end by the identification of...

Effect of chronic graft-versus-host disease on the intestine in adult BDF1 mice

This study was performed to characterize the intestinal lesions in chronic graft-versus-host disease (GVHD) in mice and to determine a possible role of intestinal intraepithelial lymphocytes (iIEL) in the development of these lesions. Chronic GVHD was induced by transfer of DBA/2 lymphocytes into non-irradiated (C57BL/10 x DBA/2)F1 (BDF1)...

Constitutive expression of LY-6.A2 on murine keratinocytes and inducible expression on TCRγδ+ dendritic epidermal T cells

We investigated the expression of Ly-6.A2 on isolated murine epidermal cells by flow cytometry. Ly-6.A2 was expressed on 61% of keratinocytes and 6% of dendritic epidermal T cells of C57BL mice. Phosphatidylinositol-specific phospholipase C removed Ly-6.A2, indicating that the antigen is anchored to the keratinocyte membrane via a glycosyl...

Vß gene family usage in spontaneous lymphomas of AKR mice: Evidence for defective clonal deletion

T-cell receptor (TCR) ß-chain usage and expression of the CD3, CD4, and CD8 differentiation antigens were analyzed in 14 spontaneous AKR lymphomas. Lymphoma cells massively infiltrated and/or proliferated in the organs analyzed (thymus, spleen, and mesenteric lymph nodes), giving rise to a loss of organ structure. One lymphoma occurred only in...

The involvement of the intestinal microflora in the expansion of CD4+ T cells with a naive phenotype in the periphery

It is well known that immune reactivity declines with age. Recently, we demonstrated that the age-related decrease in IL-2 production by CD4+ T cells was accompanied by an increased production of IL-4 and interferon-gamma (IFN-gamma). This age-related shift in the profile of lymphokine production was related to phenotypic changes within the CD4+...