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Among the responders to microbial invasion, neutrophils represent the earliest and perhaps the most important immune cells that contribute to host defense with the primary role to kill invading microbes using a plethora of stored anti-microbial molecules. One such process is the production of reactive oxygen species (ROS) by the neutrophil enzyme complex NADPH-oxidase, which can be assembled and active either extracellularly or intracellularly in phagosomes (during phagocytosis) and/or granules (in the absence of phagocytosis). One soluble factor modulating the interplay between immune cells and microbes is galectin-3 (gal-3), a carbohydrate-binding protein that regulates a wide variety of neutrophil functions. Gal-3 has been shown to potentiate neutrophil interaction with bacteria, including Staphylococcus aureus, and is also a potent activator of the neutrophil respiratory burst, inducing large amounts of granule-localized ROS in primed cells. Herein, the role of gal-3 in regulating S. aureus phagocytosis and S. aureus-induced intracellular ROS was analyzed by imaging flow cytometry and luminol-based chemiluminescence, respectively. Although gal-3 did not interfere with S. aureus phagocytosis per se, it potently inhibited phagocytosis-induced intracellular ROS production. Using the gal-3 inhibitor GB0139 (TD139) and carbohydrate recognition domain of gal-3 (gal-3C), we found that the gal-3-induced inhibitory effect on ROS production was dependent on the carbohydrate recognition domain of the lectin. In summary, this is the first report of an inhibitory role of gal-3 in regulating phagocytosis-induced ROS production.

Supplementary Figure Legends 1-3 from Recruitment and Activation of Natural Killer Cells In vitro by a Human Dendritic Cell Vaccine

Supplementary Figure 3 from Recruitment and Activation of Natural Killer Cells In vitro by a Human Dendritic Cell Vaccine

Recruitment of circulating natural killer (NK) cells into inflamed lymph nodes is known to provide a potent, IFN-γ–dependent boost for Th1-polarized immune responses in mouse models. Such NK cell recruitment into draining lymph nodes is induced by certain s.c. injected adjuvants, including mature vaccine dendritic cells (DC), and is mediated by a CXCR3-dependent pathway. Here, we show that monocyte-derived immature human DCs stimulated with polyinosinic acid:polycytidylic acid, IFN-α, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IFN-γ, α-type 1–polarized DC (αDC1), secrete profuse amounts of the CXCR3 ligand CXCL9/MIG and substantial amounts of CXCL10/IP-10 and CXCL11/I-TAC after withdrawal of maturation stimuli. In sharp contrast, no measurable production of these chemokines was found in DCs after maturation with the current gold standard maturation cocktail for human DC-based cancer vaccines consisting of TNF-α, IL-1β, IL-6, and prostaglandin-E2 (PGE2-DC). PGE2-DCs preferentially produced the Th2 and regulatory T-cell–attracting chemokines CCL17/TARC and CCL22/MDC, whereas only marginal levels of these chemokines were produced by αDC1s. Functional studies in vitro showed that supernatants from mature αDC1s actively recruited CD3−CD56+ NK cells and that adding anti-CXCL9/MIG antibodies to the αDC1 supernatant substantially reduced this recruitment. Finally, αDC1s were able to induce IFN-γ production when cocultured with resting autologous NK cells, but only if concurrent CD40 ligation was provided. These novel findings indicate that injected human αDC1-based vaccines have the potential to recruit and activate NK cells during their arrival to draining lymph nodes and that this feature may be of relevance for efficient priming of Th1 cells and CTLs. [Cancer Res 2008;68(14):5965–71]

Supplementary Figure 2 from Recruitment and Activation of Natural Killer Cells In vitro by a Human Dendritic Cell Vaccine

Supplementary Figure 1 from Recruitment and Activation of Natural Killer Cells In vitro by a Human Dendritic Cell Vaccine