IFN-alpha-mediated suppression of low-affinity FC(epsilon) receptors on Peyer's patch lymphocytes and augmentation of soluble CD23: implications for IgE responses.
The ability of interleukin (IL)-6 or interferon-alpha (IFN-alpha) to regulate expression of low-affinity Fc(epsilon) receptor (CD23) and serum levels of CD23 was studied in benzylpenicilloyl-keyhole limpet hemocyanin-sensitized BALB/c mice at the peak of a hapten-specific immunoglobulin E (IgE) antibody-forming cell (AFC) response. These responses are analogous to those observed in human atopic disease. To induce peak IgE responses, mice were injected intraperitoneally with BPO-KLH (10 micrograms) in aluminum hydroxide gel (alum) on days 0, 21, and 42. On day 44, mice were injected subcutaneously with IL-6 (100-1000 U) or IFN-alpha (1000-10,000 U). On day 46, numbers of CD23+ lymphocytes in Peyer's patches (PP), mesenteric lymph nodes (MLN), and spleen and levels of soluble CD23 in serum were determined (flow microfluorimetry and enzyme-linked immunosorbent assay, confirmed by competition assay). Data are expressed as percent total cells or as optical density at 490 nm. IFN-alpha treatment strongly suppressed (up to 100%) numbers of CD23+ cells exclusively in PP (i.e., numbers of CD23+ cells in MLN and spleen were unchanged) whereas serum levels of soluble CD23 were dramatically increased (60%). IL-6 treatment had no effect on either numbers of CD23+ lymphocytes or on serum levels of soluble CD23. The data suggest that the mechanism(s) by which IFN-alpha, but not IL-6, regulates IgE responses involves suppression of CD23 expression on lymphocytes in PPs and supports a central role for these organs in regulation of IgE responses in vivo.
Miller
H
H
Department of Pathology, State University of New York Health Science Center at Brooklyn, 11203, USA.
Bluth
M H
MH
Chice
S M
SM
Durkin
H G
HG
Auci
D L
DL
D000818:Animals; D007073:Immunoglobulin E / Q000096:biosynthesis*; D016898:Interferon-alpha / Q000494:pharmacology*; D015850:Interleukin-6 / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D010581:Peyer's Patches / Q000276:immunology*; D017455:Receptors, IgE / Q000032:analysis / Q000187:drug effects*
D016898:Interferon-alpha; D015850:Interleukin-6; D017455:Receptors, IgE; D007073:Immunoglobulin E