Influence of aluminium on the immune system--an experimental study on volunteers.

The purpose of this study was to examine whether oral exposure to aluminum (Al) can affect the human immune system. Eighteen healthy volunteers (mean age 42, 28-57 yr) were divided into a test group (9 females, 4 males) and a referent group (3 females, 2 males). Over 6 weeks, the test subjects ingested 10 ml of antacid (aluminum hydroxide, 59 mg Al/ml) three times daily.

Ex vivo PKH26-labelling of lymphocytes for studies of cell migration in vivo.

A prerequisite for studies of cell migration is that the cells of interest can be appropriately labelled and subsequently easily traced. The use of radioisotopes or fluorescent substances that bind covalently to the cell surface, e.g.

Phenotype transition of CD4+ T cells from CD45RA to CD45R0 is accompanied by cell activation and proliferation.

An investigation of proliferation and activation events in subsets of human CD4+ cells, defined by their expression of CD45RA and CD45R0, is reported. A single-laser based assay for the study of multiple surface antigens and two-parameter cell cycle analysis was used for sorting of and subsequent analysis of proliferation in CD4+CD45RA+ CD45R0-, CD4+CD45RA-CD45R0+ subsets and phenotypically intermediate stages. After labelling with BrdUrd, cells were sorted with flow cytometry on the basis of light-scattering properties and staining with anti-CD45RA, anti-CD45R0, and anti-CD4 markers.

Multicolor flow cytometric analysis of the CD45 antigen provides improved lymphoid cell discrimination in bone marrow and tissue biopsies.

Samples from bone marrow or non-hematopoietic tissue such as solid organ biopsies often contain an excess of non-leukocytes exhibiting lymphocyte-like light scatter characteristics, making it sometimes difficult to define satisfactory light scatter lymphocyte gates. To circumvent this, we describe here a multiparametric method of identifying lymphoid cells by expression of the CD45 antigen, in conjunction with light scatter parameters. A 'third color'-conjugated anti-CD45 antibody was included with every FITC/PE double staining, thereby permitting live or list mode analysis gating on CD45 positive cells.