8 T-cell differentiation occurs by a complex transcriptional programme initiated by TCR and environmental signals but it is also accompanied by epigenetic changes at specific loci.9 We first review the transcription factors that are activated downstream of TCR signalling and then explore certain principles that might operate in regulating them. Signalling through the TCR activates at least three families of transcription factors: nuclear factor of activated T cells (NFAT), activating protein 1 (AP-1) and nuclear factor-κB (NF-κB) (see Fig. 1). Gene expression Selleck EGFR inhibitor by these transcription factors is not restricted to

T cells but rather is found in almost every cell type in the body. As a result, extensive biochemical analysis has been performed over the years describing

the network of interacting proteins that activate them. We will briefly review the regulation of these factors in T cells. The NFAT family consists of five members: NFAT1 (NFATp or NFAT c2), NFAT2 (NFATc or NFATc1), NFAT3 (NFATc4), NFAT4 (NFATc3) and NFAT5; NFAT3 is not expressed in immune cells. All NFAT proteins contain a conserved Rel homology domain (regulatory domain) and an NFAT homology domain (DNA-binding domain). All except NFAT5 are regulated by calcium.10 NFAT is a transcription factor that is normally resident in the cytoplasm and is de-phosphorylated by a calcium-dependent phosphatase, calcineurin. This de-phosphorylation activates it and causes its translocation into the nucleus.11 Nuclear export of NFAT is mediated by phosphorylation. Glycogen find more synthase kinase 3 (GSK-3) is known to phosphorylate conserved serine residues necessary for nuclear export.12 In peripheral lymphocytes, antigen receptor signalling leads to the rapid inactivation of GSK-3. Activators of PKA suppress interleukin-2 (IL-2) production and T-cell activation, consistent with the possibility that NFAT is a substrate for protein kinase A (PKA).12 NFAT4 is known to be negatively regulated through phosphorylation by casein kinase 1 in the cytoplasm.13 Another mechanism of negative regulation of NFAT involves calcipressin, a target of NFAT that

binds to and inhibits calcineurin.10 Members of the homer family have been shown to bind to NFAT and compete with calcineurin, hence negatively regulating NFAT Metalloexopeptidase activation.14 Nuclear retention of NFAT can also be achieved by sumoylation, adding another level of complexity in its regulation.15 Unlike NFATc2, which is constitutively transcribed in T cells, transcription of the NFATc1 gene in effector T cells is strongly induced within 3–4 hr of TCR and co-receptor stimulation.16 Members of the NFAT family are redundant, as the mice lacking individual NFAT proteins show mild alterations in immune function whereas more severe defects are observed when more than one member is knocked out.10 NFAT plays a crucial role in T-cell differentiation.

In addition, the entire contents of the resuspended biofilm were plated onto LB10 agar supplemented with 300 μg mL−1 of rifampicin (Sigma Aldrich) to quantify the number of spontaneous rifampicin-resistant mutants. The plates were incubated for 2 days at 37 °C after which time CFUs were enumerated. The mutation frequency was calculated as the number of spontaneous rifampicin-resistant mutants divided by the total viable population. The ability of each variant to utilise different buy Venetoclax substrates as carbon sources was determined using the commercially available

BIOLOG GN2 plates (Biolog, CA) according to the manufacturer’s instructions (minor modifications as below). Each plate contains 95 different carbon sources, each conjugated to a tetrazolium

dye. The ability to utilise a specific substrate results in dye cleavage and the formation of a purple hue in the wells. In brief, bacterial cultures were grown overnight in 10 mL of M9 medium (supplemented check details with 5.5 mM glucose) at 37 °C with shaking. Following centrifugation (4580 g) and washing (twice with 10 mL PBS), bacteria were resuspended in 20 mL of GN2 inoculating fluid (Biolog). The BIOLOG GN2 plates were then inoculated with 150 μL of the resuspended bacteria and incubated at 37 °C. The OD600 nm was taken at 0, 4, 8 and 24 h (Wallac Victor2 plate reader; Perkin Elmer) to monitor the growth of cells within each well. A dye release profile corresponding to the amount and types of carbon sources metabolised was generated for the 24-h time point. The quantification of attachment Sucrase and batch biofilm formation was conducted on both polystyrene- (hydrophobic) (Sarstedt Inc) and tissue culture–treated (hydrophilic) (Costar, Corning Inc) 96-well microtitre plates using an assay similar to that described previously (O’Toole & Kolter, 1998; Pratt & Kolter, 1998; Koh et al., 2007). Briefly, for attachment, 100-μL aliquots of overnight cultures in LB10 were added into the wells, while for biofilm formation, overnight cultures were diluted 1 : 100 in LB10 broth. Subsequently, 100-μL aliquots of the diluted cultures were added into the wells,

and the plates were incubated without agitation at 37 °C for 2 h for attachment and/or 24 h with shaking for biofilm formation. After incubation, the cell density of each well was determined (OD600 nm), the cell suspensions were removed, the wells were washed twice with PBS, 100 μL of filtered 1% (w/v) crystal violet (CV) solution was added into each well, and the plates were incubated at room temperature for 20 min. The CV solution was removed, and the wells were washed three times with PBS followed by the addition of 100 μL of HPLC-grade absolute ethanol (Univar) to extract the CV for quantification at OD490 nm. For the attachment assay, the CV reading was normalised using the cell density reading (OD490 nm/OD600 nm).

0 mg/dL) levels were high, although other IgG subtypes were normal. Serum immunofixation did not demonstrate M protein, and the level of serum soluble IL-2 receptor was normal. The serum levels of κ (20.6 mg/dL) and λ (18.5 mg/dL) free light chains and the κ/ λ ratio (1.11) were also normal. The patient also did not have any donor specific antigens. A contrast-enhanced CT scan revealed a non-enhanced mass at the renal hilum

and some contrast defect areas in the renal cortex and diffuse marked enlargement of the graft, although no lymph node swelling was observed (Fig. 2A). An MRI also showed a hilum mass lesion with high intensity on T2-weighted images GSK2126458 mw and low intensity on diffusion-weighted images. A PET-CT scan only detected a light integrated

mass of the hilum. Based on these findings, the patient was suspected of having IgG4-RKD. As the renal function of the patient was stable at that time, a no-treatment follow-up strategy was considered appropriate. However, her renal function deteriorated gradually and the serum ABT-263 mw IgG4 level remained high (>400 mg/dL). In November 2012, the patient’s serum creatinine level had increased to 1.56 mg/dL. A biopsy was therefore carried out that showed almost the same findings as the biopsy 2 years after transplantation, although some severe fibrotic lesions and infiltration of IgG4-positive plasma cells were observed directly under the renal capsule. Because of the deterioration in renal function, the methylprednisolone dose was increased to 16 mg/day. Three months after this increase in steroid dose, the hilum mass disappeared on a CT scan (Fig. 2B), but cytomegalovirus antigenmia, JC virus viruria and viraemia screening became positive. An over-immunosuppression state was therefore suspected, and the methylprednisolone dose was decreased to 8 mg/day and mycophenolate mofetil changed to mizoribine. Loperamide Five months after the initial increase in steroid

dose, a follow-up biopsy in May 2013 showed that plasma cell infiltration in the renal interstitium had decreased markedly, although focal and segmental severe interstitial fibrosis and tubular atrophy with IgG4-positive plasma cells were observed (Fig. 3). Serum IgG4 levels decreased immediately after the increase in steroid dose and remained at <100 mg/dL thereafter. The patient's serum creatinine level also remained stable at around 1.6 mg/dL. The clinical course of the patient is shown in Figure 4. IgG4-RKD usually manifests as plasma cell-rich tubulointerstitial nephritis (TIN), although its clinicopathological features are not well described. Raissan et al. showed that most patients with overt IgG4-RKD had acute or progressive chronic renal failure, involvement of other organ systems, radiographic abnormalities such as small peripheral low-attenuation cortical nodules or diffuse marked enlargement of the kidneys, and elevated IgG4 serum levels (>135 mg/dL).

It is conceivable that adjuvants which create Ag depot at the site of injection target Ag to tissue-derived DCs.7 The persistent pMHCII presentation by tissue-derived DCs, APCs known find more to express high levels of pMHCII and costimulation molecules,51 could favour the maintenance

of low-affinity clonotypes in the CD4 T-cell repertoire. On the other hand, dispersible adjuvants may target Ag to less stimulatory APCs, such as inflammatory monocytes or naïve Ag-specific B cells that skew CD4 T-cell responses towards higher-affinity clonotypes. The differential capacity of APC subtypes to process and present Ag could also play an important role in determining the specificity of the CD4 T-cell response.52–54 APCs differ in their ability to capture Ag, their expression of endolysosomal proteases55,56

and their expression of DM Decitabine concentration and DO molecules.57,58 Demotz and colleagues have shown that different cell lines incubated in vitro with HEL protein generated distinct sets of peptides containing the same core determinant, suggesting that the presentation of one determinant by different types of APCs can stimulate populations of T cells with distinct fine Ag specificities.59 In the same Ag model, Kanellopoulos and colleagues have shown that DCs focused an HEL-specific CD4 T-cell response in vitro against a single immunodominant I-Ed-restricted peptide, while B cells also presented a subdominant I-Ad-restricted peptide, thereby diversifying the T-cell response.60 Hence, by targeting different APCs, adjuvants can alter the immune repertoire of the Ag-specific CD4 T-cell response (Fig. 2d). A number of post-translational changes in MHC-bound peptides have been shown to occur in APCs upon the internalization of native Ag

proteins, including the nitration of tyrosines, the oxidation of tryptophans61,62 and the citrullination of arginine.63 These peptide modifications, when affecting TCR contact residues, are recognized by CD4 T cells that are distinct from cells specific for unmodified peptides.61–63 Unanue and colleagues have reported that some of these modified peptides are generated in vivo after immunization ADAMTS5 with native protein61 but their overall impact on the CD4 T-cell repertoire remains poorly defined. Whether adjuvants differ in their ability to generate these post-translational changes is equally unclear. In addition to these chemical modifications, there is also evidence that a given pMHCII complex assumes multiple conformations that can be identified by CD4 T cells (Fig. 2e).64,65 While most CD4 T cells (type A) recognize a stable pMHCII conformer selected by DM molecules, some T cells (type B) recognize a less stable conformer generated in recycling endosomes and eliminated by DM in late endosomes.

We also performed structural analysis by MALDI-TOF-MS. Whole lipids were extracted from both types of cell with organic solvent systems (15). Lipids from AP-61 (1.1 × 1010) and LLC-MK2 (5.7 × 109) cells yielded 230 and 360 mg, respectively. Lipid components in AP-61 cells were further separated by latrobeads (Latron Laboratory, Tokyo, Japan) column chromatography and high-performance liquid chromatography equipped with silica gel column. Once separation was complete, the lipid samples were subjected to TLC analysis using plastic TLC plates

(Polygram Sil G, Nagel, Germany). The plates were developed with a mixture of isopropanol/H2O/25% ammonium (75:25:5, v/v/v), and treated with orcinol reagent for detection of GSLs. Nine neutral GSL fractions, AP1 to AP9, were prepared from AP-61. TLC/virus-binding assay was carried out as described previously (15, 16). AZD0530 in vitro Briefly, the GSLs selleck compound that had been resolved on TLC plates were incubated overnight at 4°C with DENV (3.8 × 107 FFU) diluted

in PBS containing 1% ovalbumin and 1% polyvinylpyrrolidone. After washing three times, the plates were incubated at room temperature for 1 hr with human anti-dengue antiserum from patients with dengue hemorrhagic fever. This was followed by incubation with HRP-conjugated goat anti-human immunoglobulin as the secondary antibody. After washing three times, the plates were visualized with a Konica immunostaining HRP-1000 kit (Konica, Tokyo, Japan). Under our experimental conditions for the TLC/virus-binding assay other envelope viruses, such as influenza virus, do not bind to neutral GSLs, including nLc4Cer (16). Figure

1 shows the TLC profiles of the whole neutral GSLs and the neutral GSL fraction AP2 from AP-61 cells with orcinol reagent staining Clomifene (Fig. 1a and c). In the neutral GSLs of AP-61 and C6/36, one prominent signal was detected with the same mobility with authentic L-3. TLC-immunostaining assay with anti-L-3 antibody clearly demonstrated that the prominent GSL from AP-61 was authentic L-3 (Fig. 1d). TLC/virus-binding assay showed that one neutral GSL from the AP-61 cells with the same mobility as authentic L-3 reacted strongly with DENV-2 (Fig. 1b). To further characterize L-3 from AP-61 cells, fraction AP2 was treated for 24 hr at 37°C with β-N-Acetyl-D-hexosaminidase, and subjected to chemical and immunochemical detection with anti-L-3 antibody (data not shown). TLC analysis demonstrated that the major GSL in AP2 was converted to authentic L-2 by the enzyme treatment. These findings indicate that AP-61 cells contain the L-3 molecule. Finally, we confirmed the carbohydrate structure of the major GSL in AP2 as L-3 by MALDI-TOF-MS (data not shown). Molecule ion ([M-Na]+) was observed at 1114.

The frequency of cells producing CCL3 among selleck chemical tetramer+

CD8+ T cells was also twice as high and equivalent to that of mice immunized with wt Lm (Fig. 1C) suggesting that increasing the immunizing dose of secA2−Lm restored the ability of reactivated memory CD8+ T cells to secrete CCL3 in vivo. Of note, this analysis gave comparable results on two distinct mouse genetic backgrounds and over three distinct naturally presented Lm-derived H2-Kd-restricted epitopes 19 and the H2-Kb-restricted SIINFEKL OVA-derived model epitope (Table 1). Therefore, protective immunity in mice immunized with wt and 107secA2−Lm correlates with CCL3 expression and higher numbers of effector memory CD8+ T cells. Thus, we established an original experimental system using different doses of the same mutant bacteria that do or do not prime protective immunological memory, and in which the signals integrated by the priming APCs are likely distinct. Efficient induction of long-term protective immunity requires the escape and the growth of Lm in the cytosol of infected cells 16, 20. We therefore looked for the

cell subsets that sustain active Lm growth inside their cytoplasm in vivo. To define such cells, mice were immunized i.v. with 106 or 107secA2−Lm-expressing GFP that is only expressed by viable Lm as GFP expression is rapidly lost Alpelisib solubility dmso upon bacterial death 16. 2.5, 5 and 10 h later, spleens were harvested and stained with cell surface markers allowing the discrimination of the different myeloid-derived cell subsets containing live bacteria (Supporting Information Figs. 2 and 3). At both early time points analyzed (2.5 and 5 h), CD8α+ cDCs were the main subset of cells expressing GFP (75.2 and 64.4 % respectively), and containing viable bacteria (Supporting Information Fig. 3A), 16), as also reported for wt Lm21. Interestingly, intracellular

staining of spleen cells using serum against Lm antigens, which detects both live and dead Lm as well as secreted bacterial antigens, showed that innate phagocytes, Cediranib (AZD2171) i.e. neutrophils, inflammatory monocytes and macrophages, represented 69 and 62% of the positive spleen cells 2 and 5 h after the immunization respectively (Fig. 2 and data not shown), a result supporting their role in the uptake and the killing of Lm22. Therefore, while CD8α+ cDCs represent 20–30% of the Listeriapos cells, they are the major cell type exhibiting live Lm (65–75%), likely providing the most ‘hospitable’ intracellular environment for Lm growth in vivo. Since CD8α+ cDCs are permissive to Lm growth, it makes them likely to integrate and convey signals from cytoplasmic bacteria early after immunization. Previous reports showed that CD8α+ and CD8α− cDCs prime naïve Lm-specific CD8+ T cells with equivalent efficiency when loaded with exogenous peptide ex vivo 11.

Subsequently, the sections were incubated with horseradish peroxidase-conjugated rabbit anti-mouse immunoglobulin (Vector Laboratories Inc., Burlingame, CA) diluted 1 : 1000 for see more 30 min at room temperature. The bound antibodies were visualized with 3,3′-diaminobenzidine tetrahydrochloride. The numbers of α-smooth muscle actin-positive cells were counted in three high-power (× 400) fields of each section and averaged. Fibroblastic cell line Rat-1 cells (RIKEN BioResource Center, Ibaraki, Japan) were grown at 37 °C under 5% CO2 in Dulbecco’s modified Eagle’s medium (Nacalai Tesque, Tokyo, Japan) supplemented with

10% fetal bovine serum (Biowest, Nuaillé, France) and antibiotics (100 U mL−1 penicillin, 100 μg mL−1 streptomycin; Nacalai Tesque). The cells were seeded in 12-well plates at 4 × 104 cells

per well. When the cells became subconfluent, a medium containing 1, 10, 50 and 100 μM 3-oxo-C12-HSL or 0.1% DMSO was added. After 24 h of treatment, the buy SAHA HDAC cells were fixed with 4% paraformaldehyde in phosphate buffer for 20 min at room temperature, washed three times in PBS containing 0.05% Tween 20 (T-PBS) for 5 min and incubated for 30 min at room temperature with the same anti-α-smooth muscle actin primary antibody as that used for the tissue histological examination. After washing in T-PBS, the cells were incubated with a biotinylated anti-mouse immunoglobulin G secondary antibody (Vector Laboratories Inc.) diluted 1 : 1000 in PBS for 30 min at room temperature. The cells were then washed in T-PBS and incubated with Texas-red-conjugated avidin (Vector Laboratories Inc.) for 30 min at room temperature in the dark. The nuclei were stained with Hoechst 33258. Tacrolimus (FK506) The stained cells were observed using a DMI 4000 B fluorescence microscope (Leica, Wetzlar, Germany). The percentages of α-smooth muscle actin-positive cells relative to the total cell count were calculated to evaluate the effects of 3-oxo-C12-HSL on fibroblast differentiation. RNA samples were collected from

cultured cells treated with 10 μM 3-oxo-C12-HSL using Nucleospin® RNA II (Macherey-Nagel GmbH and Co., Duren, Germany) according to the manufacturer’s instructions. RT-PCR amplifications were performed for Cox-2, transforming growth factor (TGF)-β1, and interleukin-6 (IL-6). cDNA was generated using a High Capacity cDNA Reverse Transcription Kit (Invitrogen, Carlsbad, CA) according to the manufacturer’s instructions. For quantitative PCR, the amplification of the target-specific region of cDNA was performed by 40 cycles of 95 °C for 15 s and 60 °C for 1 min after preheating at 95 °C for 10 min, and monitored using a real-time PCR system (ABI prism 7700, Applied Biosystems). The relative expression level of the target genes of the AHL-treated cells to the value of the DMSO control was calculated by the Ct method using β-actin gene as an internal control.

This research was supported by Science Foundation Ireland (grant no. 08/IN.1/B1843 and CSET grant no. 07/CE/B1368) and the Marie Curie International Re-integration Grant programme. The authors have no conflicts of interest to declare. Fig. S1. Bcl-3 mRNA levels in normal (N, n = 11), Crohn’s disease (CD, n = 10) and ulcerative colitis (UC, n = 10) colon tissue. Data extracted from the NCBI GEO data set GDS1330. Fig. S2. Relative levels of cleaved caspase-3 normalized

to β-actin levels in colon tissue from untreated (open bars) and dextran-sodium sulphate (DSS)-treated (filled bars) wild-type and Bcl-3−/−. Levels were quantified form immunoblot analysis presented in Fig. 6b in the main text. “
“Additional progression markers for human immunodeficiency virus (HIV) infection are warranted. In this study we related antigen-specific responses in CD4+ and CD8+ T cells Tanespimycin cell line to CD38, reflecting chronic immune activation, and to CD4+ T cell loss rates. Clones transiently expressing CD107a (CD8+) or CD154 (CD4+) in response to Gag, Env

and Nef overlapping peptide pools were identified, along with their expression of the inhibitory programmed death-1 receptor (PD-1) in fresh peripheral blood mononuclear cells (PBMC) from 31 patients off antiretroviral treatment (ART). HIV-specific CD8+ T cell responses dominated over CD4+ T cell responses, and among CD8+ responses, Gag and Nef responses were higher than Env-responses (P < 0·01). PD-1 on CD8+ HIV-specific subsets was higher than CMV-specific CD8+ cells (P < 0·01), whereas PD-1 on HIV-specific CD4+ cells was similar to PD-1 selleck inhibitor on CMV-specific CD4+ cells. Gag and Env CD8+ responses correlated oppositely to the CD4 loss rate. Env/Gag CD8+ response ratios, independently of PD-1 levels, correlated more strongly to CD4 change rates (r = −0·50 to −0·77, P < 0·01) than the total number of

Gag-specific CD8+ cells (r = 0·44–0·85, P ≤ 0·02). The Env/Gag ratio performed better than CD38 and HIV-RNA in logistic regression analysis predicting CD4 change rate as a measure of progression. In conclusion, HIV-specific CD8+CD107a+ Env/Gag response ratio was GPX6 a stronger predictor for progression than CD38 and HIV-RNA. The Env/Gag ratio may reflect the balance between possibly beneficial (Gag) and detrimental (Env) CD8+ T cell responses and should be explored further as a progression marker. Anti-retroviral treatment (ART) effectively reverses immune deficiency in human immunodeficiency virus (HIV)-infected individuals who have HIV-related symptoms or opportunistic infections; however, the immune system is better preserved when ART is started early in an asymptomatic phase [1]. For such patients, low current CD4+ T cell counts have predominated as an indication for ART, accompanied by secondary criteria such as rapid CD4 decline or high HIV-RNA concentrations [2–5].

Furthermore, host genetics play a direct role in shaping the intestinal microbiota [38]. A major function of SIg may be to ensure a homeostatic relationship with the intestinal microbiota by forcing a selective pressure on emerging microbial phylotypes and thereby preventing unwanted perturbations of the intestinal microbiota [18, 33]. Recent reports have shown that dysbiosis may be caused by mutations in the innate immune system

[39-41]. Here, we have demonstrated that the absence of pIgR, and hence SIgA, alters the intestinal microbial community. This provides direct evidence for SIgA as a regulator of the intestinal microbiota. Interestingly, we found a significant compartmentalization of bacteria within the cecum in WT mice, but

not in pIgR KO animals. In WT mice only were there significant differences RO4929097 nmr JQ1 cell line in the microbiota harvested from the luminal content versus that harvested from the mucosal surface. Thus, our results suggest that SIgA is not only important to maintain the overall beneficial gut microbiota, but also support appropriate compartmentalization within the lumen. Furthermore, we confirmed the increased abundance of the verrucomicrobial mucin degrading genre Akkermansia with DSS treatment (Fig. 4), which is in line with recent observations showing that the relative abundance of members of the phylum Verrucomicrobia was increased in DSS-induced colitis in mice [26]. Furthermore, phylotypes related to B. vulgatus, which have been shown to be mildly colitogenic [27], were more abundant in DSS-treated mice than in control mice that received PRKACG only normal drinking water. A previous report found no differences in the dominant microbiota of 10-week-old pIgR KO mice cohoused with WT littermates [42]. Here, we performed a detailed phylogenetic analysis of the intestinal microbiota of pIgR KO and WT mice targeting bacterial 16S rRNA genes, and found that the composition of the microbiota was significantly altered both in cecal samples and in fecal samples in the absence of pIgR. The increased resolution of analysis of the bacterial communities

in our study might have enabled us to detect differences that were previously unseen; or alternatively, coprophagy by cohoused mice in the former study could have obscured any intrinsic differences between the two genotypes. Notably, to reduce the possibility that any of these differences might be due to different environmental factors, the two genotypes were generated from mating of heterozygous mice and expanded for six generations under uniform conditions in the same breeding room. In agreement with Murthy et al. [43], we found that pIgR KO mice, now on a BALB/c genetic background, showed increased susceptibility to DSS-induced colitis compared with WT BALB/c mice. We also found a similar difference between WT mice and pIgR KO when both genotypes were on a C57BL/6 background, the same genetic background used by Murthy et al. ([43] and data not shown).

[59] Dasatinib, a Src kinase inhibitor and a preclinical drug for chronic-phase chronic myeloid leukaemia,[60] is also on the study list. As reported, Selleck PF2341066 dasatinib could reduce MMP9+ macrophage density and inhibit MMP9 expression in the tumour microenvironment.[61] This observation broadened the therapeutic mechanisms of dasatinib. To deplete TAMs by targeting their surface molecules with immunotoxin-conjugated agents is another approach for tumour therapy. Such studies have been conducted for ovarian cancer treatment by using immunotoxin-conjugated mAbs, where the surface proteins of TAMs, such as scavenger

receptor-A and CD52, were targeted.[62, 63] Folate receptor β (FRβ) is another surface protein worth targeting because it is over-expressed in M2-like TAMs,[64, 65] and the existence of FRβ+ macrophages positively associates with high vessel density, high incidence of haematogenous metastasis and a poor prognosis in patients with pancreatic cancer.[66] Nagai et al.[64] reported the inhibitory effects of the folate–immunotoxin conjugate on tumour growth, accomplished with the depletion of TAMs. One benefit of this approach may be that while pro-tumoral M2 TAMs could be depleted, the M1 tumoricidal ones are not affected. Recent studies demonstrate that several bacteria prefer to take macrophages as targets. For instance, it was reported Dabrafenib nmr that

Shigella flexneri infection could selectively induce the apoptosis of macrophages,[67] and a single injection of an attenuated strain of Shigella flexneri to tumour-bearing mice resulted in the apoptosis of TAMs, followed by a 74% reduction in size of tumours.[68] In addition, other bacteria, such as Salmonella typhimurium, Listeria monocytogens, Chlamydia psittaci and Legionella pneumophila, are

also considered to be useful for TAM-targeted immunotherapy because they harbour primarily in macrophages.[21] Other than directly inducing the apoptosis of TAMs as mentioned above, another available approach for TAM suppression is to evoke acquired immune responses, in which cytotoxic T lymphocytes act as the scavengers of TAMs because they can naturally target the membrane molecules of macrophages. why In other words, up-regulating the membrane molecules that could be recognized by T cells in TAMs would be a potential method of TAM depletion. One such molecule is legumain, a lysosomal protease highly expressed in many human tumours; which promotes neoplastic cell invasion and metastasis.[69] Luo et al.[24] originally found that legumain is over-expressed in M2-like TAMs. In the following studies, they immunized tumour-bearing mice with a novel legumain-based DNA vaccine, and found that this vaccine activated dendritic cells, which then triggered multi-step reactions including the antigen presenting, co-stimulation of cytotoxic CD8+ T cells and the specific abrogation of legumain-expressing TAMs.