second model, the two main conditions were parametrically modulated by the two categories, respectively (SOM, S5.1). The activation of the precuneus was higher for hard dominance-solvable games than for easy ones ( Fig. 4A and table S10). The activation of the insula was higher for the highly focal coordination games than for less focal ones ( Fig. 4B and table S11). Previous studies also found that precuneus activity increased when the number of planned moves increased (40, 41). The higher demand for memory-related imagery and memory retrieval may explain the greater precuneus activation in hard dominance-solvable games. In highly focal coordination games, the participants may have felt quite strongly that the pool students must notice the same salient feature. This may explain why insula activation correlates with NCI.Participants might have disagreed about which games were difficult. We built a third model to investigate whether the frontoparietal activation correlates with how hard a dominance-solvable game is and whether the activation in insula and ACC correlates with how easy a coordination game is. Here, the two main conditions were parametrically modulated by each participant's probability of obtaining a reward in each game (SOM, S2.2 and S5.2). We found a negative correlation between the activation of the precuneus and the participant's probability of obtaining a reward in dominance-solvable games ( Fig. 4C and table S12), which suggests that dominance-solvable games that yielded lower payoffs presented harder mental challenges. In a previous study on working memory, precuneus activity positively correlated with response times, a measure of mental effort (24). Both findings are consistent with the interpretation that subjective measures reflecting harder tasks (higher efforts) correlate with activation in precuneus. A positive correlation between insula activation and the participant's probability of obtaining a reward again suggests that coordination games with a highly salient feature strongly activated the "gut feeling" reported by many participants (Fig. 4D and table S13). A previous study found that the subjective rating of "chills intensity" in music correlates with activation of insula (42). Both findings are consistent with the interpretation that the subjective intensity of how salient a stimulus is correlates with activation in insula.As mentioned, choices were made significantly faster in coordination games than in dominancesolvable games. The results of the second and third models provide additional support for the idea that intuitive and deliberative mental processes have quite different properties. The "slow and effortful" process was more heavily taxed when the dominance-solvable games were harder. The "fast and effortless" process was more strongly activated when coordination was easy.

Background: WC1 co-receptors are group B scavenger receptor cysteine-rich molecules that are found exclusively on γδT cells and are thought to be encoded by a multi-gene family. Previous studies have shown γδT cells that respond to a particular stimulus have unique WC1 molecules expressed. Prior to the onset of the studies described here only one full-length WC1 nucleotide sequence was publicly available, though three WC1 molecules had been distinguished based on monoclonal antibody reactivity. Furthermore, the number of WC1 genes found in the bovine genome and their sequences had not yet been resolved.

Workshop cluster 1 (WC1) molecules are transmembrane glycoproteins uniquely expressed by cd T cells. They belong to the scavenger receptor cysteine-rich superfamily and are encoded by a multi-gene family, which is divided on the basis of antibody reactivity, into three groups, WC1.1, WC1.2, and WC1.3. The potential role of WC1 as a co-stimulatory molecule for the cd TCR is suggested by the presence of several tyrosinebased motifs in their intracellular domains. In this study, we found that WC1 was constitutively phosphorylated in ex vivo bovine cd T cells and associated with src family tyrosine kinases. Crosslinking of WC1 molecules resulted in an increase in WC1 phosphorylation and co-crosslinking of WC1 and cd TCR together prolonged WC1 phosphorylation. We identified the second tyrosine residue as the primary phosphorylation target in WC1.1 and WC1.2 intracellular sequences in both in vitro and in vivo assays. The cytoplasmic tails of WC1.1 and WC1.2 were phosphorylated on serine and PKC activity was required for PMA-induced endocytosis of WC1.1 or WC1.2. We found that phosphorylation of the second tyrosine in the WC1 cytoplasmic domain was required for the WC1-mediated potentiation of TCR-induced T-cell proliferation, suggesting that WC1 acts as a co-stimulatory molecule for cd TCR.Key words: Bovine . Cell surface molecules . gd T cells . Signal transduction IntroductionIn adult chickens, ruminants and pigs, unlike in mice and humans, gd T cells can constitute 30% of total PBMC [1]. A majority of these gd T cells in ruminants bear the glycoprotein lineage marker Workshop cluster 1 (WC1) on their surface. Based on the profiles of their gene expression, WC1 1 gd T cells of cattle represent the inflammatory population, whereas WC1 À gd T cells are regulatory cells [2,3]. WC1, a member of the scavenger receptor cysteine-rich (SRCR) superfamily, is categorized into group B along with CD5, CD6, and CD163, based on the organization of cysteine residues in its extracellular SRCR domains [4]. Like the SRCR family member SpSRCR, which is expressed in the immune cells of the purple sea urchin [5], WC1 molecules are products of a large gene family, and thus have the potential to increase the diversity of immune responses independently of the adaptive immune response receptor, i.e. the TCR.Bovine gd T cells express at least three known variants, WC1.1, WC1.2, and WC1.3, which are defined by antibodies recognizing unknown epitopes on their SRCR domains [6]. WC1.1 and WC1.2 are expressed on two mostly non-overlapping subsets of bovine gd T cells, and WC1.3 is expressed on a small 254subpopulation of WC1.1 1 cells. Cytokine production and cellular proliferation in response to stimulation vary according to the forms of WC1 expressed by gd T cells [7]. Ex vivo WC1.1 1 gd T cells, but not WC1.2 1 gd T cells, proliferate well to the gd T-cell antigens of Leptospira, and produce IFN-g in response to either antigen or 8].The correlation of the expression of a variable WC1 gene product with a cellular immune response to antigen su...

Limited studies have addressed the ability of cd T cells to become memory populations. We previously demonstrated that WC1.1 + cd T cells from ruminants vaccinated with killed Leptospira borgpetersenii proliferate and produce IFN-c in recall responses. Here we show that this response is dependent upon antigen-responsive CD4 T cells, at least across transwell membranes; this requirement cannot be replaced by IL-2. The response was also dependent upon in vivo priming, since cd T cells from leptospira vaccine-naive animals did not respond to antigen even when co-cultured across membranes from antigen-responsive PBMC. cd T cells were the major antigen-responding T cell population for the first 4 wks following vaccination and replicated more rapidly than CD4 T cells. Primed WC1 + cd T cells circulated as CD62L hi /CD45RO int /CD44 lo , characteristics of T CM cells. When stimulated with antigen, they decreased CD62L, increased CD44 and CD25, and had no change in CD45RO expression. These changes paralleled those of the leptospira antigen-responsive CD4 T cells but differed from those of cd T cells proliferating to mitogen stimulation. This system for in vivo cd T cell priming is unique, since it relies on a killed antigen to induce memory and may be pertinent to designing vaccines that require type 1 pro-inflammatory cytokines.

BackgroundThe scavenger receptor cysteine rich (SRCR) domain is an ancient and conserved protein domain. CD163 and WC1 molecules are classed together as group B SRCR superfamily members, along with Spα, CD5 and CD6, all of which are expressed by immune system cells. There are three known types of CD163 molecules in mammals, CD163A (M130, coded for by CD163), CD163b (M160, coded for by CD163L1) and CD163c-α (CD163L1 or SCART), while their nearest relative, WC1, is encoded by a multigene family so far identified in the artiodactyl species of cattle, sheep, and pigs.ResultsWe annotated the bovine genome and identified genes coding for bovine CD163A and CD163c-α but found no evidence for CD163b. Bovine CD163A is widely expressed in immune cells, whereas CD163c-α transcripts are enriched in the WC1+ γδ T cell population. Phylogenetic analyses of the CD163 family genes and WC1 showed that CD163c-α is most closely related to WC1 and that chicken and platypus have WC1 orthologous genes, previously classified as among their CD163 genes.ConclusionSince it has been shown that WC1 plays an important role in the regulation of γδ T cell responses in cattle, which, like chickens, have a high percentage of γδ T cells in their peripheral blood, CD163c-α may play a similar role, especially in species lacking WC1 genes. Our results suggest that gene duplications resulted in the expansion of CD163c-α-like and WC1-like molecules. This expanded repertoire was retained by species known as "γδ T cell high", but homologous SRCR molecules were maintained by all mammals.