Differential effects of iron deficiency on the expression of CD80 and CD86 co-stimulatory receptors in mitogen-treated and untreated murine spleen cells

✍ Scribed by Solo R. Kuvibidila; Connie Porretta

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 226 KB
• Volume: 86
• Category: Article
• ISSN: 0730-2312
• DOI: 10.1002/jcb.10206

✦ Synopsis

The interaction of CD28 and its ligands (CD80, CD86) on antigen presenting cells and that of TCR/CD3-MHC are required for T lymphocyte activation. To determine whether impaired lymphocyte proliferation associated with iron deficiency is due to reduced expression of these ligands, spleen cells obtained from eight to nine C57BL/6 mice/group of iron deficient (ID), iron replete (R), control (C), pair-fed (PF), and high iron (HI) mice were labeled with anti-CD80-fluorescein isothiocyante (FITC) and anti-CD86-FITC. Diets differed only in iron concentration: 5, 50, and 125 mg/kg for the ID, C, and HI, respectively. Mean levels of hemoglobin and liver iron stores of ID and R mice were less than 50% those of C mice (P < 0.005). In non-activated and concanavalin A-treated cultures, significant differences were observed among groups in the percentage of CD80 + cells: ID>R > C = PF = HI (P < 0.05). The same trend was observed for CD86 + cells (P > 0.05). Fluorescence intensity (FI) of either marker did not significantly change by iron status. In vitro iron chelation by deferoxamine (20, 200 microg/ml) for 1, 2, and 24 h increased FI of both markers on unactivated B and T cells (P < 0.05). However, it had no effect on FI of either marker of mitogen-treated cells presumably because the maximum levels are achieved by the mitogen. Lymphocyte proliferative responses to mitogens positively and significantly correlated with CD80 and CD86 FI (r = 0.41-0.59) but negatively correlated with the percentages of CD80 + cells (r = -0.48) (P < 0.05). Data suggest that impaired lymphocyte proliferation associated with iron deficiency is not due to reduced CD80 and CD86 expression.