8% in 2008).[16] In the Australian dialysis population, infection accounted for 11% of mortality, the third most common cause of death following dialysis withdrawal (35%) and cardiac disease (43%)[17] Of the 11% (n = 148), approximately 25% was secondary to bacterial septicaemia. Similarly, 17% of mortality was attributed to infection in the New Zealand dialysis population. CRI has an enormous adverse impact, not only at individual level of increased morbidity and mortality, but also financial implications with the costs of hospital admissions, antibiotics use and catheter change. Cost-per-infective-episode has been estimated to be between US$3703 and US$29 000 in the USA from non-tunnelled catheters in intensive care

units.[18] With the high incidence of catheter use in incident haemodialysis patients, it is imperative to develop strategies to prevent see more and treat CRI. There have been studies examining the application of topical agents to the exit site to prevent both local and systemic infections. Intense interests have been concentrating on the use of antimicrobial lock solutions (ALS) to reduce CRI in recent years. Once bacteraemia has occurred, catheter removal, with or without delay in insertion of a new vascular catheter, is often indicated. Alternative therapy such as combining systemic antibiotics and ALS, without changing the catheter, has been evaluated in the literature. The objective of this guideline is to identify appropriate recommendations for central ICG-001 solubility dmso venous catheter insertion and catheter care, as well as prevention and treatment of CRI in dialysis patients with tunnelled catheters in-situ. Dressing type, frequency of dressing changes and cleansing solutions will be addressed. The use of topical agents or intraluminal lock solutions will be investigated as will be the various treatment strategies for CRI. The use of real-time ultrasound guidance is strongly recommended for the placement of haemodialysis catheters and results in improved rates of successful catheter

placement, and reduced rates of both haematoma formation and inadvertent arterial puncture. (Level 1 evidence) (Suggestions are based on Level III and IV evidence) The adherence to strict aseptic technique is proven to reduce the catheter related bacteraemia rate and all units should therefore audit this practise. Tunnelled haemodialysis Fenbendazole catheters should be used as they are associated with lower rates of catheter related bacteraemia, catheter dysfunction and vascular damage (venous trauma, and stenosis) compared with temporary non-tunnelled catheters. The right internal jugular vein is the preferred insertion site with respect to ease of access and lower rates of short and long-term complications. In ICU settings, subclavian catheter placement has excellent short-term outcomes compared with jugular and femoral approaches but has significant long-term sequelae recommending against their use.

On the other hand, earlier restoration of renal function may mitigate cardiovascular risks associated with uremia, potentially preventing significant cardiovascular morbidity and mortality. Observational studies seemed to suggest that earlier transplantation does not appear to be associated with better patient and graft survival. A retrospective review of 19,471 first-time preemptive renal transplant recipients reported to the UNOS data7 between January 1, 1995 and December 31, 2009, showed that annual mean estimated GFR (eGFR) at the time of pre-emptive transplant ranged

from 9.2 ml/min/1.73 m2 to 13.8 ml/min/1.73 m2. Nonetheless, the authors did not detect any statistically significant differences in patient or death-censored graft survival between strata of eGFR at the time of transplant. It is noteworthy that to Ridaforolimus in vivo date, there is no randomized controlled trial available, from which to draw substantive conclusions on the optimal timing for renal transplantation prior to the initiation of dialysis therapy. While most preemptive renal transplants are from a living donor, up to a quarter of these transplants occur with deceased donors. Therefore, it also raise to question the timing for listing these patients, balancing the chances of receiving a deceased donor kidney prior to dialysis initiation and optimizing resources in maintaining these potential

recipients on the list. Analysis of the Scientific Nutlin-3a manufacturer Registry of Transplant Recipients database of Sulfite dehydrogenase 57,677 renal transplant candidates8 demonstrated that a higher renal function at listing was strongly associated with a greater likelihood of receiving a preemptive transplant and a significantly better survival advantage. Mean eGFR at listing was 14.8 ml/min/1.73 m2 and the adjusted odds ratio for preemptive transplant was 1.45 per 5 ml/min/1.73 m2 increase in eGFR. Unfortunately, available literature is again mainly observational

and retrospective in nature. In summary, preemptive renal transplantation appears to confer superior allograft and patient survival benefit, reasons for which are multifactorial and mainly related to patient selection, correction of the uremic milieu and even unknown factors peculiar to the procedure itself. Outcomes of the transplant did not seem to differ when stratified by the eGFR at the time of transplant, but placing these patients on the waitlist early increases their odds of having the transplant performed preemptively. 1. Wolfe RA, Ashby VB, Milford EL et al. Comparison of mortality in all patients on dialysis, patients on dialysis awaiting transplantation, and recipients of a first cadaveric transplant. N Engl J Med 1999; 341:1725–1730. 2. Meier-Kriesche HU, Port FK, Ojo AO et al. Effect of waiting time on renal transplant outcome. Kidney Int 2000; 58:1311–1317. 3.

CD4− CD8α+ CD11b− DCs (CD8+

cDCs) are localized in the T-cell zone and specialize in MHC class I presentation. JNK inhibitor CD4− CD8 α− CD11b+ DCs have also been identified and are called DN cDCs.[9, 32] All three subtypes of DCs were significantly increased in the spleens from Fli-1∆CTA/∆CTA mice compared with wild-type controls. On the other hand, Fli-1∆CTA/∆CTA B6 mice had increased pre-cDCs and monocyte populations in PBMCs compared with wild-type littermates (Fig. 3). Despite the significant increase of macrophage and DC populations in spleens from Fli-1ΔCTA/ΔCTA mice, these mice did not show any phenotypic pathology. There were also no pathological changes in bone marrow from Fli-1ΔCTA/ΔCTA mice. The pDC population in the spleens from Fli-1∆CTA/∆CTA mice was significantly increased when compared with wild-type

littermates (Fig. 2). The pDCs are strong producers of type I interferon, and type I interferon signature is linked to development of learn more systemic lupus erythematosus.[1, 6] Expression of Fli-1 is implicated in lupus disease development in both human patients and animal models of lupus.[25-27] However, the interferon level in the serum is not detectable from Fli-1ΔCTA/ΔCTA mice (data not shown). It is interesting to note that Fli-1∆CTA/∆CTA mice had significantly increased pDCs in the spleen but not in PBMCs, expression levels of MHC on pDCs in the spleens from Fli-1ΔCTA/ΔCTA mice were similar compared with those from wild-type Lonafarnib nmr mice. Further study is needed to address this difference. We have found that the pre-cDC populations in BM from Fli-1ΔCTA/ΔCTA mice were not significantly different compared with that from wild-type mice, however, both the cDC and pre-cDC populations in spleens from Fli-1ΔCTA/ΔCTA mice were higher compared with wild-type controls (Figs 1 and 2). We do not know the mechanisms that result in the increase in the pre-cDC population in the spleen of

Fli-1ΔCTA/ΔCTA mice, one possibility may be a change in the migration of pre-cDCs in Fli-1ΔCTA/ΔCTA mice and more pre-cDCs are actively attracted into the spleen in these mice. The increase in cDC populations in spleen suggests that pre-cDC cells may mature in lymphoid tissues like the spleen, outside the bone marrow. Several studies have demonstrated that stromal cells play an important role in immune cell development and that gene-deficient stromal cells affect normal immune cell development.[33, 34] Our bone marrow transplantation study clearly demonstrated that the expression of Fli-1 in both HSCs and stromal cells affects mononuclear phagocyte development. We found that Fli-1∆CTA/∆CTA B6 mice receiving BM cells from wild-type B6 mice (WF) had a significantly increased population of monocytes in PBMCs when compared with wild-type B6 mice receiving BM from wild-type B6 mice (WW).

Similarly, HSV has been described to modulate the level of costimulatory molecules expressed on both T cells and DCs [[48]]. Moreover, influenza virus, in contrast to HSV, is capable of eliciting CD4+ T-cell

help-independent CD8+ T-cell priming, presumably due to its ability Venetoclax molecular weight to upregulate CD40L on DCs. Furthermore, the pathogen-induced inflammatory milieu may also account for the ability to instruct T-cell help-independent CD8+ T-cell responses. We have previously shown that upon infection with vaccinia virus, IL-12 is induced in a T-cell help-dependent manner [[26]], whereas certain other virus infections (e.g., LCMV) induce potent Type-I IFN responses at the expense of IL-12 production [[49]]. In contrast to IL-12 induction after vaccinia virus infection, Type-I IFN production after LCMV infection is T-cell selleck screening library help-independent and is

therefore a candidate molecule driving T-cell help-independent CD8+ T-cell responses. In support of this hypothesis, we could show that differences in the T-cell help-dependence between various infections is chiefly influenced by the ability of a specific infectious agent to stimulate an early robust production of Type-I IFN [[50]]. There is also extensive evidence that signals via the IL-12 receptor or Type-I IFN receptor initiate a differentiation program which involves increased expression of numerous genes that encode for proteins important for clonal expansion and survival of both effector and memory cells [[51, 52]]. However, all of

these studies cannot exclude a synergistic effect between direct Type-I IFN signaling on CD8+ T cells and additional signals provided by other cell types, as it has been reported that the immune stimulatory activity of Type-I IFN results at least partly from its ability to induce DC maturation [[53]]. In conclusion, the current data suggest that in infections/ immunizations, which lead to robust CD4+ T cell-independent Ribose-5-phosphate isomerase Type-I IFN production, CD4+ T-cell help is not required for primary CD8+ T-cell responses, as long as APC maturation is provided by the infecting agent or an adjuvant. In the case of infections/immunizations, which are associated with a predominant IL-12 response, the CD4+ T-cell dependence of primary CD8+ T-cell responses may relate to whether sufficient IL-12 production by the priming APC requires engagement with CD4+ T cells. Finally, in the case of “weak” immunogens, which do not by themselves promote the maturation of DCs, CD4+ T cells are required not only to induce inflammatory third signals for CD8+ T-cell activation but also to induce DC maturation (Fig. 1).

Media was replaced every 2 days for a total culture time of 9 days. For CFSE (Molecular Probes, Eugene, OR, USA) labeling, 5 × 107/mL T cells were incubated in prewarmed PBS containing 1 μM CFSE for 10 min at 37°C followed by extensive washing and resuspension in PBS for adoptive transfer. Mixed BM chimeras in which only the αβ T cells lack 4–1BB were generated using TCRα−/− and 4–1BB−/− mice as described previously [49]. For the generation of the 4–1BBL−/− BM chimeras, 5 × 106 congenically marked 4–1BBL−/− or WT BM cells were used to reconstitute lethally irradiated WT or 4–1BBL−/− mice. All irradiated BM reconstituted mice were given water supplemented with 2 mg/mL of neomycin

sulfate (Bio-Shop, Burlington, Ontario,

Canada) during the first 4 weeks, and they were further rested for an additional 2 months before use. Three million OT-I T cells, prepared as above, were delivered i.v. to the mice and their recovery Roscovitine from spleen, LN, and BM analyzed 30 days later. Influenza A/PR8 and A/HKx31 viruses were grown in eggs and their tissue culture infectious dose determined by infection of MDCK cells [50]. Age- and sex-matched mice were used for infection. A dose of 100 HAU influenza A/X31 in 200 μL volume was used for primary intraperitoneal infection. Influenza A/X31 primed mice were rested for at least 30 days before challenge with influenza A/PR8 at a dose of 100 HAU in 200 μL intraperitoneally. Analysis of influenza NP366–374-specific CD8+ T cells using MHC tetramers as well as CD107a and intracellular cytokine staining LEE011 ic50 following a 6-hour restimulation was carried out as previously described [28]. H-2Db/NP366–374

tetramers were provided by the National Institute for Allergy and Infectious Diseases tetramer facility (Emory University, Atlanta, GA, USA). Uninfected mice were used as negative controls for Db/NP366–374 tetramer staining. Isotype or fluorescence minus one controls were used as negative controls for cytokine staining. Congenically marked OT-I TCR transgenic cells were tracked using PE- or allophycocyanin-anti-mouse CD45.2 (eBioscience), Pacific Blue-anti-CD45.1 (Biolegend), FITC-anti-Vβ5.1 (BD Biosciences), biotin-anti-Vα2 and PerCP-anti-mouse CD8+ (BD Biosciences). Other antibodies used in this study included Ponatinib chemical structure allophycocyanin-anti-mouse IFN-γ, FITC-anti-CD107a, PE- or PE-Cy5- or allophycocyanin-anti-CD44, FITC-anti-Ter119, Pe-Cy7- or PE-anti-mouse CD3, biotinylated-anti-mouse-4–1BB (clone 3H3), Alexa Fluor450- or PE-anti-B220, PE-, PE-Cy7- or allophycocyanin-anti-CD11c, Alexa Fluor488 anti-Gr1, PE-anti-Ly-6C, PE-anti-MHC-II, PE-Cy7-anti-F4/80, PerCP- or PE-Cy7-anti-CD11b, PE-Cy5.5-anti-mouse TCRβ, PE-Cy5.5-anti-mouse CD19, and FITC-anti-PDCA-1. The 4–1BB-deficient mouse was used as a negative control for analysis of 4–1BB expression on CD8+ T cells. Detection of 4–1BBL was done by i.v.

The ‘instructive’ model hypothesized that all fates could be adopted by every naïve cell. By now, the ‘instructive’ model has been validated by showing that cells that had been partially differentiated towards

the Th2 phenotype could be re-educated to become Th1 cells [91, 106]. Many different signals have been described as being potentially instructive for Th cells, and much study has gone into which signals induce which phenotype. But how does the adaptive immune response choose a correct phenotype? The adaptive immune system of B and T lymphocytes is built on top of the so-called innate immune system composed of intracellular responses, neutrophils, granulocytes and natural killer cells. The members of the innate immune system

detect the presence of pathogens by evolutionary conserved signals that are usually called pathogen-associated molecular patterns (PAMPs) [107]. One important class of cellular www.selleckchem.com/products/AT9283.html receptors that can detect the presence of PAMPs are the Toll-like receptors (TLR), which discriminate between bacterial, viral and several other types of PAMPs [1, 108]. The innate system therefore uses evolutionary conserved information and is probably selected to mount an appropriate immune response Wnt inhibitor to particular pathogens. Because innate cells and infected cells secrete cytokines, these cytokines provide a key to the developing Th0 cells to adopt a particular phenotype [99]. Thus, the local

context of cytokines created by the innate immune Org 27569 responses can instruct helper T cells to make an appropriate decision. One notorious example of Th decision-making is the priming with formalin-inactivated and alum-adjuvated RSV vaccine (FI-RSV). In the 1960s, a trial with this vaccine failed because it predisposed for enhanced disease rather than preventing it [109]. This was attributed to the generation of Th2 responses rather than the more appropriate Th1 response. Subsequent mouse studies into RSV have shown that immunization with the RSV fusion protein (F) or the RSV attachment protein (G) induces Th1 or Th2 responses when challenged with RSV [110]. Again the Th2 type response was associated with enhanced disease, including a marked eosinophilia reminiscent of that seen in FI-RSV-primed mice. Induction of these skewed Th2 responses can be abrogated by the insertion of a CD8 epitope derived from the RSV M2 protein into the G protein or by simultaneous priming of mice with G and M2 proteins prior to RSV infection [111]. This demonstrates that the presence or absence of a CD8+ T-cell epitope could play a role in determining the type of immune response against a pathogen. The absence of a CD8+ epitope appears to predispose for the formation of Th2 immunity. Conversely, in the presence of a CD8+ T-cell response, the CD4 T cells adopt a Th1 phenotype.

The origin seems multi-factorial, but to an important extent explainable by prednisolone action. Gene signatures in patients with AAV undergoing steroid treatment should therefore be interpreted accordingly. “
“The endotoxic activities of lipopolysaccharides (LPS) isolated from different strains of rhizobia and rhizobacteria (Bradyrhizobium, Mesorhizobium, and Azospirillum) were compared to those of Salmonella enterica sv. Typhimurium LPS. The biological activity of all the examined preparations, measured as Limulus lysate gelation, production of tumor necrosis factor (TNF), interleukin-1β (IL-1β),

and interleukin-6 (IL-6), and nitrogen oxide (NO) induction in human myelomonocytic cells (line THP-1), was considerably lower than that of the reference enterobacterial endotoxin. Among the rhizobial lipopolysaccharides, the activities of Mesorhizobium see more huakuii and Azospirillum lipoferum LPSs were higher than those of the LPS preparations from five strains of Bradyrhizobium. The weak endotoxic activity of the examined preparations was

correlated with differences in lipid A structure compared to Salmonella. Soil bacteria belonging to the rhizobium lineage are able to fix atmospheric nitrogen during symbiosis with legume plants. Bacteria from the genus Bradyrhizobium induce nitrogen-fixing nodules on the roots of cultivated (Glycine max and Glycine soya) and wild-growing legumes (1, 2). M. huakuii induces the formation of nodules on the roots of Astragalus sinicus (3). A. lipoferum represents plant-growth-promoting rhizobacteria which colonize the root surface and are not able to penetrate root http://www.selleck.co.jp/products/AG-014699.html cells. They live in association phosphatase inhibitor library with roots of grasses, cereals, and other monocotyledonous plants (4, 5). Lipopolysaccharide, as an integral component of the cell walls of Gram-negative bacteria, plays an essential role in the proper development of symbiotic relationships (6). LPS, together with Omp proteins, is responsible for the asymmetric structure and semi-permeability of outer membranes. This is important for the appropriate morphogenesis and functionality of bacteroids, endosymbiotic forms of rhizobia which perform nitrogen

fixation (7). LPS may play a role in the protection of rhizobia against plant defense response mechanisms. Suppression of systemic acquired resistance or hypersensitivity reaction has been shown during infection of plant tissues by microsymbionts (8–10). Most pathogenic bacteria possess LPSs displaying endotoxic activity against host organisms. Lipid A, the part of LPSs that anchors the whole macromolecule in the outer membrane, is the centre of endotoxicity. The fine structure of enterobacterial lipid A has been identified as a glycolipid comprised of a β-(1,6)-linked glucosaminyl disaccharide substituted by two phosphate groups at positions C-1 and C-4 and six fatty acid residues with two acyloxyacyl moieties with a distinct location (Fig. 1) (11, 15, 16).

Increasing numbers of APC were co-cultured in round-bottom 96-well plates and in complete medium with 105 CFSE-labeled OT-II cells previously enriched by negative selection using a cocktail of PE-labeled mAb, anti-PE microbeads (Miltenyi) and LD columns (Miltenyi). At day 5, CFSE dilution was determined by flow cytometry. A fixed number of Calibrite™ beads (BD) were added

to each sample to quantify the absolute number of OT-II cells per well. Naïve CD4+ T cells, defined as CD25−FR4−CD62LbrightCD44lowCD4+, were purified from CD4-enriched (Dynal® Mouse CD4 Gemcitabine order negative isolation kit, Invitrogen) spleen and total lymph node cells on a MoFlo™ or FACSAria™ (BD) cell sorter. The population was routinely more than 98% pure and free of Foxp3+

cells (not shown). Before transfer, T cells were labeled with 2 μM of CFSE, washed and resuspended in PBS. An amount of 1–2×106 cells were adoptively transferred into CD45.1+ or CD45.2+ congenic B6 mice. One day later, mice were injected i.v. or in the footpad with indicated amount of OVA323–339-coupled mAb alone or in combination with 40 μg BMS 907351 poly I:C or 100 μg curdlan. CD4+ T-cell responses were assessed 4–6 days after immunization or at the indicated time points. Red-blood-cell-depleted splenocytes were restimulated in complete medium with either 10 μg/mL of OVA323–339 peptide or 10 ng/mL of PMA (Sigma) and 1 μg/mL of ionomycin (Calbiochem). After 30 min, Brefeldin A (Sigma) was added to the culture at a final concentration of 10 μg/mL, and the cells were incubated for three more hours. Alternatively, in some experiments, splenocytes were restimulated for 3 days in complete medium with or without 10 μg/mL of OVA323–339 peptide. Cytokine accumulation in the supernatant was then monitored by ELISA. Flat-bottom 96-wells plates (MaxiSorp™ Nunc-immunoplates) were coated with 2 μg/mL of 7H11 mAb. After overnight Cisplatin manufacturer incubation, unbound mAb was washed away (PBS, 0.05% Tween 20) and non-specific binding sites were blocked with PBS supplemented with 2.5% FBS and 0.2% NaN3. Serially diluted sera were then plated and incubated for 6 h

at room temperature. After six washes, bound Ab were detected with biotinylated anti-mouse IgG1 (B68-2, BD) or anti-mouse (5.7, BD) mAb or with biotin-SP-conjugated anti-mouse IgG F(ab′)2 (Jackson Immunoresearch). Plates were then washed extensively and incubated with extravidin®-conjugated alkaline phosphatase (Sigma). After six washes, the presence of bound Ab was revealed using p-Nitrophenyl phosphate (Sigma). Wells were considered as positive when the value of the absorbance measured at 405 nm was superior to the one obtained with the serum from a PBS-injected mouse+3x SEM. The Ab titer corresponds to the last dilution scoring positive. This study was funded by Cancer Research UK. C. R. S. acknowledges the support of the Fondation Bettencourt-Schueller.

Fluconazole has been used extensively with an unknown impact on susceptibility. Selleck RXDX-106 To investigate antifungal susceptibility trends in clinical vaginal isolates of C. albicans from 1986 to

2008, microdilution susceptibility was performed on randomly selected single isolates. Minimum inhibitory concentrations (MICs) were determined for: fluconazole, clotrimazole, miconazole, ketoconazole, itraconazole, voriconazole, flucytosine and amphotericin B. The MIC90 for each drug was then calculated for the time periods: 1986–1989, 1992–1996 and 2005–2007. A total of 250 C. albicans vaginal isolates were included. The MIC90 (mcg ml−1) for fluconazole was 0.25, 0.5 and 0.5 mcg ml−1 for each grouping, respectively. The corresponding MIC90 for flucytosine was 1, 2 and 8 mcg ml−1, respectively. The MIC90 for the remaining agents remained unchanged across time periods mentioned. PLX4032 Of note, the percentage of isolates with MIC ≥1 and ≥2 mcg ml−1 for fluconazole increased from 3% to 9% over the study period. Although the C. albicans MIC90 to fluconazole in vaginal isolates has not shown a clinically significant increase since 1986, there is an increasing number of isolates with elevated MICs. The implications of this increase are unknown,

but given the achievable vaginal concentrations of fluconazole, reduced susceptibility may have clinical relevance. “
“Candidemia in cancer patients may differ according to the type of cancer. To characterise the epidemiology and outcome of candidemia in cancer patients from Brazilian hospitals, we compared the characteristics of patients with hematologic malignancies (HM) and solid tumours (ST). A retrospective study was performed, based on data collected from laboratory-based surveillance studies in 18 tertiary care hospitals between March/2003

and December/2007. The characteristics of patients with HM (n = 117) were compared with patients with ST (n = 248). Predictors of 30-day mortality were identified by uni- and multivariate analyses. Candidemia in HM was more likely to occur in the setting of chemotherapy, corticosteroids, neutropenia, mucositis and tunnelled central venous catheter Amobarbital (CVC), whereas surgery, intensive care unit admission and invasive procedures (mechanical ventilation, parenteral nutrition and CVC) were more frequent in ST. The 30-day mortality rate was higher in the ST group (65% vs. 46%, P = 0.001). Factors significantly associated with 30-day mortality were older age and intensive care unit admission. Important differences in the epidemiology and outcome of candidemia in HM and ST were observed. The characterisation of the epidemiology is important to drive preventive measures and to select appropriate therapies. “
“Cryptococcus isolates from Cuban patients were identified as C. neoformans var. grubii. Although this species has since long been associated with bird droppings, a recent genotyping study provided strong evidence for additional origins of exposure.

CD37 negatively regulates

T-cell proliferation [14]; therefore, a contribution of aberrant T lymphocytes to poor CD37−/− cellular responses observed in CD37−/− mice must be considered. However, it is difficult to argue that in vitro hyperproliferation could manifest in vivo as an inability to mount an effective IFN-γ response. The defect is not due to an inherent inability of stimulated CD37−/− T cells to secrete IFN-γ (Fig. 2E–F and 3E), to altered frequencies of T cells such as Treg cells (Supporting Information Fig. 1), or to skewing of CD37−/− T-cell responses away from an IFN-γ-secreting Th1 cell phenotype. IL-12 is produced normally in CD37−/− DCs (Supporting Information Fig. 2) and T-cell IL-4 (Fig. 2A–C) responses were minimal for both WT and CD37−/− mice. Moreover we could detect no defects in activated Staurosporine ic50 CD37−/− T-cell homing to lymphoid organs (data not shown). By contrast there are several lines of evidence that point to an impairment in DC migration in CD37−/− mice. First, despite CD37−/− DCs being potent stimulators of T

cells in vitro [15], immunized CD37−/− mice Doxorubicin show impaired priming of adoptively transferred WT T cells, and CD37−/− DC induce poor T-cell responses when injected into WT recipients, showing a defect in the biology of CD37−/− DC in vivo (Fig. 3). Second, in vivo and in vitro experiments point to a significant impairment in migration that was intrinsic to CD37−/− DCs (Fig. 4). This observation was extended by in vivo visualization of DC migration in WT and CD37−/− mice, via multiphoton confocal microscopy (Fig. 5). Initial experiments revealed no difference in spontaneous dermal DC migration, consistent with the absence of a phenotypic difference between WT and CD37−/− naïve mice [10]. Subsequently, we examined the response of dermal DCs to a local inflammatory irritant, oxazolone. The WT response to this treatment was a period of cessation Lck of DC migration, as described previously for DCs that encounter danger signals [26], followed by a recovery of migration some hours later. As DCs typically migrate to the LN following local inflammatory stimulation, the latter response

presumably models this phase of DC behavior. The absence of CD37 had its most significant effect on DC migration during this second phase, reducing both the velocity and directionality of migration. The combination of these two deficits would be expected to markedly reduce the efficiency of DC migration toward dermal lymphatics en route to the LN, a hypothesis supported by analysis of both in vivo DC migration in the FITC painting model (Fig. 4A), and the poor recovery of injected CD37−/− BMDCs in DLNs (Fig. 4E–F). Taken together, the evidence supports a model where an impairment in DC migration is a major contributing factor to the poor adaptive cellular immunity induced in CD37−/− mice; the CD37−/− DCs do not arrive in DLNs in sufficient numbers to effectively induce an adequate cellular immune response.