Impaired accessory cell function in a human dendritic cell line after human immunodeficiency virus infection.

We generated human dendritic cell (DC) hybridoma cell lines by fusing HGPRT-deficient promonocytic U937 cells with immature DCs obtained by culturing peripheral blood monocytes with interleukin-4 (IL-4; 1,000 U/ml) and granulocyte-macrophage colony-stimulating factor (100 U/ml) for 7 days and mature DCs by treatment with tumor necrosis factor alpha (12.5 microg/ml) for 3 days. Only one fusion with immature DCs was successful and yielded four cell lines--HB-1, HB-2, HB-3, and HB-9--with an overall fusion efficiency of 0.

Accessory cell function of airway epithelial cells.

Accessory cell function of airway epithelial cells. We previously demonstrated that airway epithelial cells (AECs) have many features of accessory cells, including expression of class II molecules CD80 and CD86 and functional Fcgamma receptors. We have extended these studies to show that freshly isolated AECs have mRNA for cathepsins S, V, and H [proteases important in antigen (Ag) presentation], invariant chain, human leukocyte antigen (HLA)-DM-alpha and HLA-DM-beta, and CLIP, an invariant chain breakdown product.

Induction of apoptosis by HIV-1-infected monocytic cells.

We have previously described a soluble 6000-Da peptide produced by an HIV-1-infected human macrophage cell line, clone 43(HIV), which induces apoptosis in T and B cells. We have identified this factor as the novel cDNA clone FL14676485 that encodes for the human hypothetical protein, FLJ21908. The FL14676485 cDNA clone was isolated from a 43(HIV) lambda ZAP Escherichia coli expression library and screened with a panel of rabbit and mouse anti-apoptotic Abs.