Interleukin 8 (IL-8), a member of the CXC subfamily of chemokines, is a pot
ent inflammatory cytokine produced by many cell types in response to severa
l stimuli. In an attempt to determine whether human B-cell IL-8 functions a
s an autocrine growth factor, a wide panel of B-cell lines derived from pat
ients with AIDS-associated B-cell lymphomas (AABCL) (n = 5) and from non-AA
BCLs (n = 8) was studied for expression of IL-8, IL-8 Receptor type A (IL-8
R), and secretion of IL-8 protein. Using RT-PCR and Northern Blot analysis,
we were able to observe IL-8 expression ubiquitously. However, IL-8R expre
ssion was seen only in EBV negative (4 out of 7) B-cell lines. EBV and HIV-
1 activated B-cell line; HBL-1, was the major secretor of IL-8. Our results
demonstrate that IL-8 is expressed in malignant B-cell phenotypes that cor
respond to a narrow window in the B-cell differentiation pathway (pre-B, ea
rly-B, and intermediate-B) as well as in normal CD19-enriched B-cells. Furt
hermore, IL-8 autocrine loops were not evident since IL-8R was detected onl
y in cell lines that did not secrete IL-8 protein. (C) 2001 Academic Press.