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The article presents a list of forthcoming research papers related to immunology. They include "DNA and its cationic lipid complexes induce CpG motif-dependent activation of murine dendritic cells," "Mature dendritic cells pulsed with exosomes stimulate efficient cytotoxic T lymphocyte responses and antitumor immunity," and "Involvement of IL-10 in exhaustion of myeloid dendritic cells and rescue by CD40 stimulation."

The article presents a list of articles related to immunology. The articles include "Monocyte-Derived Dendritic Cells From Horses Differ From DC of Humans and Mice," by Susanne Mauel, Falko Steinbach and Hanns Ludwig, "Extended Sequence Preferences for Oligodeoxyribonucleotide Activity," by Peter Lenert, Adam Goeken and Robert Ashman, "On the Logic of Positive Selection," by Melvin Cohn, "CTLA-4 Interacts With Stat5 and Inhibits Stat5-Mediated Transcription," by M. Srahna, L. Van Grunsven, J. Remacle and Peter Vandenberghe, and "Peritoneal Macrophages Supress T Cell Activation by Amino Acid Catabolism," by R. Matlack, K. Yeh, L. Rosini, D. Gonzalez, J. Taylor, D. Silberman, A. Pennello and James Riggs.

Presents abstracts of research papers on dendritic cells, published in the December 2002 supplement of 'Immunology.' 'Dendritic cell biology,' by M. Moser; 'Investigating the MHC-restriction of CD4[sup+]CD25[sup+] regulatory T cells,' by L.R. Ambrose.

Dendritic cell-specific intercellular-adhesion-molecule-grabbing non-integrin (DC-SIGN) is a potential target receptor for vaccination purposes. In the present study, we employed Lewis X (Lex) oligosaccharides, which mimic natural ligands, to target ovalbumin (OVA) to human dendritic cells (DCs) via DC-SIGN, to investigate the effect of this DC-SIGN-targeting strategy on the OVA-specific immune response. We demonstrated that Lex oligosaccharides could enhance the OVA-specific immune response as determined by enzyme-linked immunospot assay (ELISPOT), intracellular interferon-γ staining and 51Cr-release assay. An almost 300-fold lower dose of Lex-OVA induced balanced interferon-γ-secreting cells compared to OVA alone. Furthermore, secretion of interleukin-10, a reported mediator of immune suppression related to DC-SIGN, was not increased by Lex-OVA, either alone or together with sCD40L-stimulated groups. A blocking antibody against DC-SIGN (12507) reduced the numbers of interferon-γ-secreting cells during Lex-OVA stimulation, yet it did not prevent Lex oligosaccharides from promoting the secretion of interleukin-10 that was induced by ultra-pure lipopolysaccharide. These results suggested that the strategy of DC-SIGN targeting mediated by Lex oligosaccharides could promote a T-cell response. This DC-targeting may imply a novel vaccination strategy. [ABSTRACT FROM AUTHOR]

Dendritic cells (DC) have a potent antigen-presenting capacity for recruiting resting T cells into immune responses. They also promote expansion of already activated memory T cells. By contrast, macrophages (Mø) are only effective in stimulating memory responses.¹, ² Infection and depletion of DC occur in human immunodeficiency virus (HIV)-infected individuals and recruitment of T cells into primary responses is blocked.³ Here comparisons between DC and Mø in stimulating secondary T-cell responses in HIV infection were made. Adherent Mø, and DC isolated by a new method, were separated from peripheral blood of patients in different stages of HIV infection and from uninfected controls and added to allogeneic lymphocytes in mixed leucocyte reactions (MLR). Some were pulsed with influenza virus or tetanus toxoid and used to stimulate autologous T cells. Responses were measured from uptake of [³H]thymidine in 20 μ1 hanging drop cultures. DC, but not Mø, from normal individuals stimulated MLR but both populations stimulated secondary responses to recall antigens. DC from all HIV seropositive individuals caused little or no stimulation of any lymphocyte responses. However, Mø from HIV seropositive asymptomatic individuals and those with persistent generalized lymphadenopathy stimulated responses to recall antigens. There was no stimulation using cells from acquired immune deficiency syndrome (AIDS) patients. Blocked DC but not Mø function may underlie progressive immunological non-responsiveness in HIV infection. Without recruitment of resting T cells, loss of memory T cells4–6 may be cumulative; failure of secondary activation (e.g. by Mø) would lead to lost T-cell activity. Identification and circumvention of the defect in DC could offer new therapeutic approaches. [ABSTRACT FROM AUTHOR]

Dendritic cells (DC), which express high-density HLA class II molecules, stimulate strong primary allogeneic T-cell responses via an interaction of the T-cell receptor with major histocompatibility complex (MHC) antigens (signal 1). It is not yet clear whether they also provide a second stimulus to the responding T cell in the form of the cytokine interleukin-1 (IL-1). To clarify this point, the ability of purified human tonsil DC to produce IL-1 and to stimulate allogeneic T cells was tested. No intracellular IL-1α or β was identified in DC comparable to that readily demonstrated in monocytes, and IL-1 release from lipopolysaccharide (LPS)-stimulated DC was not detected in either a biological assay for IL-1 or an ELISA assay for IL-1β. Furthermore, strong stimulation of allogeneic T lymphocytes by DC in the mixed leucocyte reaction (MLR) was noted to occur in the absence of IL-1 production, and this stimulation was not inhibited by polyclonal antisera to IL-1α and IL-1β, which were known to inhibit IL-1-mediated thymocyte proliferation. Other HLA-class II-positive cell populations, namely peripheral blood monocytes and B cells, purified by methods which avoided DC contamination, were unable to stimulate allogeneic T cells with or without supplementary IL-1. We conclude that DC are very effective stimulators of T lymphocytes and that IL-1 is not required as a second signal for allogeneic T-cell responses. [ABSTRACT FROM AUTHOR]