At each survey, a single blood sample was obtained by finger pric

At each survey, a single blood sample was obtained by finger prick (approximately 0·3 mL) for thick and thin blood films, filter paper blood collection (Whatman 3, Maidstone, UK), Haemoglobin test (HemoCue photometer) and for a Rapid Diagnostic Tests (RDT; Orchid Biomedical Systems, Goa, India) for malaria.

Filter papers were air-dried and stored in plastic bags with silica desiccant (silica gel type III; Sigma, Dorset, UK) and stored at −20°C. Plasma was this website diluted 1 : 1 in 0·1% sodium azide in PBS (reaching a final concentration of 0·05%). Individuals were followed up for 6 months by passive case detection with those who experienced a clinical malaria attack (temperature >37·5°C with parasites at any density) treated according to national treatment guidelines. Parasites were detected using three methods; microscopy, RDT and PCR. For microscopy, 100 fields of a Giemsa stained thick blood film were examined during the surveys, and at

all occasions, when a clinical malaria episode was suspected, RDTs (RDT; Orchid Biomedical Systems) were used for immediate detection of infection in the field. For PCR, DNA was extracted from filter paper samples using the QIAamp DNA mini kit (QIAGEN, Hilden, Germany), parasite detection carried out by nested-PCR amplification of the small subunit ribosomal RNA (rRNA) gene [16]. Immunoglobulin G (IgG) antibodies MK-2206 cost were assayed by ELISA, as described previously [14, 17]. Recombinant P. falciparum apical membrane antigen (AMA-1 FVO, provided by Takafumi Tusboi, Ehime ID-8 University, Japan), merozoite surface protein 119 (MSP-119 Wellcome allele,

provided by Patrick Corran, London School of Hygiene & Tropical Medicine with permission of Tony Holder), merozoite surface protein 2 (MSP-2, Dd2 allele provided by David Cavanagh, Institute of Immunology and Infection Research, Edinburgh, UK), circumsporozoite protein (CSP; NANP16 peptide, provided by Patrick Corran, London School of Hygiene & Tropical Medicine) and Anopheles gambiae salivary antigen (gSG6 provided by Bruno Arcà, Sapienza University, Rome, Italy) were coated onto ELISA plates overnight at 4°C at a concentration of 1.25 ug/mL for AMA1, 5 μg/mL for gSG6 and 0.5 μg/mL for all the other antigens. Plates were washed using PBS plus 0·05% Tween 20 (PBS/T) and blocked with 1% (w/v) skimmed milk powder (Marvel, UK) in PBS/T. Serum samples were added in duplicate to each plate at a serum dilution of 1 : 400 for CSP, 1 : 2000 for AMA-1, 1 : 1000 for MSP-2 and MSP-119, and 1 : 100 for gSG6 in 1% bovine serum albumin (BSA) in PBS/T. A positive control of pooled hyperimmune serum collected from adults resident in a malaria endemic area was included in duplicates on each plate in a 4-fold serial dilution from 1 : 50 to 1/51 200 (6 concentrations in total) to allow standardization of day-to-day and plate-to-plate variation.

In addition, the cytokine imbalance of psoriasis is clearly illus

In addition, the cytokine imbalance of psoriasis is clearly illustrated by therapeutic response PF-02341066 nmr to IL-4 [56]. Patients treated with recombinant human IL-4 showed a reduction of clinical scores, lesional Th1 cells, and the IFN-γ/IL-4 ratio, whereas the number of circulating Th2 cells was increased [56]. This study clearly highlights the adjustment

of the disease-specific cytokine imbalance as an important therapeutic tool. In contrast to psoriasis, the skin of atopic eczema patients is frequently colonized by staphylococci, in particular S. aureus (reviewed in [57]). This phenomenon is due to a tissue-restricted immune deficiency that relates to the Th2-dominated cytokine microenvironment typically observed in atopic eczema. In vitro, both, IL-4 and IL-13, have been shown to inhibit Th1- [47] and Th17-mediated [8] induction of antimicrobial Ivacaftor supplier peptides in epithelial cells via STAT6 and SOCS molecules [58]. The clinical relevance of these two opposing T-cell cytokine signatures has been shown in vivo in a rare population of patients suffering from both psoriasis and atopic eczema in parallel [50]. In such patients, only eczema

lesions, but not psoriasis plaques, were colonized by S. aureus [50]. Beyond insufficient epithelial immunity, a second hallmark of atopic eczema is an impaired epidermal barrier with consequent transepidermal water loss and dryness of the skin (reviewed

in [59]). While mutations in genes of the epidermal differentiation complex, such as filaggrin, are strongly associated with atopic eczema, a Th2-dominated microenvironment also damages the epidermal barrier by downregulating filaggrin and other genes of the epidermal differentiation complex [60-62]. Thus, Th2 cytokines antagonize Th1 and Th17 immunity in the skin and largely explain the phenotype of atopic eczema [57]. A third cutaneous model disease is ACD. Here, small and harmless molecules (haptens) such as nickel elicit an acute eczematous immune response characterized by T-cell cytotoxicity and keratinocyte apoptosis [63, 64]. The clinical phenotype RAS p21 protein activator 1 of ACD is largely explained by the cytokine content of the local microenvironment. Depending on the eliciting hapten, a mixed T-cell infiltrate is observed with dominating Th1 cytokines. In such a microenvironment, IL-17 functions as an amplifier of nonspecific T-cell apoptosis mediated by IFN-γ [36] and enhances the cytotoxic immune response typical for ACD. In summary, the function of T-cell cytokines strongly varies depending on the cytokine content of the local microenvironment. Therefore, the function of Th-cell subsets has to be interpreted within the context of the microenvironment and disease setting.

It is also designated as cluster of differentiation 281 (CD281)

It is also designated as cluster of differentiation 281 (CD281). It is expressed at higher levels in the spleen and peripheral blood cells [36]. Human TLR1 plays an important role in host defence against M. tb. A study in Seattle and Vietnam population identified seventeen polymorphisms in the coding region, in which seven variants

were synonymous C114T (H38H), A914T (H305L), C944T (P315L), T1583C (C528C), G1677A (P559P), T1760G (V587G), T1892G (L631R), and ten were non-synonymous G1968A (L656L), C2198T (P733L), T130C (S44P), A1482G (V494V), C1938T (H646H), G239C (R80T), C352T (H118Y), A743G (N248S), A1518G (S506S) and T1805G (I602S),with seven of them in the extracellular domain and two in the intracellular domain [37]. TLR1/2 and TLR2/6 receptor pairs exhibit different specificities towards

many microbial agonists BMS-777607 clinical trial [38-40], which is determined by the region composed of LRR motifs. Recently, a study reported that there are three nSNPs located in the LRR region of TLR1. P315L is one of the nSNPs that may have impact on the innate immune response and clinical susceptibility to many infectious diseases [41]. Studies have shown that TLR1 polymorphisms were associated with impaired cell-surface expression [42]. R80T, N248S and I602S nSNPs were associated with invasive aspergillosis [43] and with Crohn’s disease [44]. In malaria and H. pylori-induced gastric diseases, 602S was found to be a risk factor [45, 46]. A study reported in Germany found that the 743A and 1805G correlate with TLR1 deficiency and impaired Pim inhibitor functionality and were strongly associated with susceptibility to TB [42]; similarly, in African American and European American patients, common

variants like N248S and S602I and rare variants like H305L and P315L were associated with altered immune response to M.tb ligands and susceptibility to Leprosy [47]. In response to stimulation with the TLR1 ligand PAM3, the variants Liothyronine Sodium containing 602I were fully capable of mediating NF-kB signalling, while variants with SNP 602S had impaired signalling, this implies that 602I regulates lipopeptide responses. N248 (common in European Americans) is a conserved amino acid site in the extracellular domain of TLR1 and is a putative glycosylation site. Replacement of the Asn residue with Ser might result in altered glycosylation, potentially changing TLR1 folding or function [47] (Table 1). N248S G743A (rs4833095) I602S T1805G (rs5743618) H305L A1188T (rs3923647) P315L A945G (rs5743613) R677W no rs designation available R753Q (rs5743708) 2258G/A T399I C+1196T (rs 4986791) D299G A+896G (rs 4986790) +1083C/G T 361T (rs3821985) +745 T/C S249P (rs5743810) 129 C/G (rs3764879) 2167 A/G (rs3788935) 1145 A/G (rs3761624) +1A/G Met1Val (rs3764880) G+1174A rs352139 TLR2 is encoded by a DNA sequence composed of 2352 bases that codes for 784 amino acids [48].

5D) To address whether compensation by the upregulated HRs in H1

5D). To address whether compensation by the upregulated HRs in H1H2RKO and H3H4RKO CD4+ T cells affects the expression of HDC or the production of HA, anti-CD3, and soluble anti-CD28 mAb stimulated CD4+ T cells

were analyzed for HDC expression (Fig. 5E) by qRT-PCR and screened for HA production by enzyme immunoassay (EIA) (Fig. 5F) at 24, 48, and 72 h. Surprisingly, we did not detect a significant strain effect or (strain × time) interaction for HA production or HDC expression. These www.selleckchem.com/products/byl719.html data therefore do not support the existence of a compensatory loop with respect to HA production and HDC expression by H1H2RKO and H3H4RKO CD4+ T cells. However, the HR expression studies clearly indicate that disease severity in H1H2RKO and H3H4RKO mice is associated with compensatory upregulation of the corresponding receptors. Here, we have assessed the overall contribution to EAE susceptibility imposed by H1R and H2R (couple via stimulatory G proteins) and the H3R and H4R (couple via inhibitory

G proteins). The results of our study demonstrate that H3H4RKO mice develop a significantly more severe Erlotinib datasheet clinical disease course compared with B6 and H1H2RKO mice in association with greater pathology in the brain but not the spinal cord. In contrast, despite a significant difference in the severity of the clinical disease courses between B6 and H1H2RKO, a significant difference in pathology was not detected in either the brain or spinal cord, suggesting as in H3RKO mice [[18]], H1R and/or H2R may also play a significant role in central functions related to the severity of clinical signs. Increased susceptibility to EAE in H3H4RKO mice is associated with significantly higher production of IFN-γ and IL-17 in MOG35–55 specific ex vivo recall assays. In contrast, H1H2RKO mice exhibit decreased susceptibility to EAE and decreased BBB permeability. We have also shown that CD4+ T cells from H1H2RKO mice, upon in vitro activation, have an intrinsic immune deviation toward the Th2 phenotype, while activated T cells from H3H4RKO mice have an intrinsic dipyridamole immune bias toward Th1 type cells. The results of our current study

indicate that HA signaling through H1R and H2R augments EAE susceptibility by influencing antigen-specific T-cell effector responses, immune deviation, and BBB permeability. It is well known that HA and HRs modulate the innate and adaptive immune systems [[4]]. Previously, we have shown that H1RKO mice develop less severe EAE that was associated with an immune deviation of the CD4+ T-cell population from an encephalitogenic Th1 response to a protective Th2 response [[27, 31]]. In addition, mice deficient for H2R are significantly less susceptible to acute early phase EAE and T cells from immunized H2RKO mice exhibit blunted Th1 effector cell responses [[32]]. Similar to H1R, HA acting through H2R determines T-cell effector functions and their polarization.

Fluconazole has been used extensively with an unknown impact on s

Fluconazole has been used extensively with an unknown impact on susceptibility. Selleckchem Ganetespib 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. Palbociclib 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 mafosfamide (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.

Additionally, upregulation of CD69, which is a very early activat

Additionally, upregulation of CD69, which is a very early activation marker with unknown function, and 4-1BB (CD137), which is important for Etoposide in vivo T-cell survival 23 was analyzed. Stimulated CD8+ PBMC upregulated

CD25, CD69 and CD137 (Fig. 6B) but when the CD8+ PBMC were activated in the presence of M1-specific Treg clones D1.6 or D1.52, the upregulation of CD25 was partially inhibited while both CD69 and CD137 were still upregulated. This indicates that the CD8+ T cells are partly activated in the presence of Treg, but are incapacitated to respond to IL-2 required for their full expansion, consistent with the data previously reported in murine models 24. As a control, there was no effect on CD25 upregulation when the CD8+ PBMC were co-cultured with M1-specific

bulk culture. These data imply that the M1-specific Treg interfere with the IL-2 pathway both on the production of IL-2 by T-helper cells as well as the uptake of IL-2 by CD8+ effector cells. In this study we showed that the influenza M1-specific proliferative T-cell response is accompanied by the production of both IFN-γ and IL-10, similar to earlier observations in a mouse model 15. Since only low numbers of IL-10-producing CD4+ T cells were detected in the bulk cultures, the M1-specific IL-10-producing CD4+ T cells likely refers to a small population in the peripheral selleck chemicals blood. In-depth Etomidate analysis of this immune response at the T-cell clonal level revealed that M1-specific T cells could simultaneously produce IL-10 and IFN-γ. The dual production of both IFN-γ and IL-10 by T cells has been implicated in preventing lethal immunopathology during clearance of pathogens 25 and can be produced by different subtypes of CD4+ T cells, including Treg 26. Indeed, a number of the isolated

influenza-specific T-cell clones with such a cytokine profile displayed a Treg phenotype as indicated by their capacity to suppress the proliferation, and the production of IL-2 and IFN-γ of autologous T-helper type 1 cells in an antigen-dependent manner. In addition to IFN-γ and IL-2, these M1-specific Treg may also suppress the production of other cytokines, which have not been addressed in this study. The switch from single IL-10 production to IL-10/IFN-γ double production at higher antigen concentrations observed in some of the isolated Treg clones prompted us to study if increased IFN-γ production affected the suppressive capacity of the stimulated Treg. Rather, an increased antigen dose led to higher suppression. This fits well with a recent study on CD4+ IL-10/IFN-γ-producing T cells in mice showing that IFN-γ signaling enhanced the production of IL-10 and had an essential role in the inhibitory capacity of these T cells 27, suggesting that the observed switch to dual production in our Treg clones may reflect increased suppressive capacity.

, 2010) Truly nonencapsulated pneumococci may be a cause of outb

, 2010). Truly nonencapsulated pneumococci may be a cause of outbreaks of mucosal disease particularly conjunctivitis and have been related to acute otitis media (Martin et al., 2003; Hanage et al., 2006). Thus, nonencapsulated pneumococci Selleckchem LY2109761 may be highly contagious and cause mucosal disease (Martin et al., 2003). The microbial and host factors that determine carriage are still incompletely characterized. Neutrophils recruited by IL-17 expressing CD4+

T cells seem to contribute to mucosal clearance of pneumococci (Malley et al., 2005; Zhang et al., 2009). Neutrophils kill and degrade bacteria by a range of mechanisms including reactive oxygen species and antimicrobial peptides. The concept has emerged that neutrophil proteases such as neutrophil elastase and cathepsin G also contribute significantly to intracellular and extracellular killing of bacteria PDGFR inhibitor (Reeves et al., 2002; Pham, 2006). Thus, neutrophil proteases may be effective in killing bacteria even in the absence of effective phagocytosis. Patients with

deficiency of neutrophil serine protease activity due to Papillon–Lefevre syndrome suffer impaired host defence clinically evident as severe periodontitis and pyogenic liver and renal abscesses (Van Dyke et al., 1984; Almuneef et al., 2003). The importance of neutrophil elastase and cathepsin G for intracellular and extracellular killing of S. pneumoniae by neutrophils was demonstrated recently and may be relevant for colonization (Standish & Weiser, 2009). Extracellular neutrophil protease is present

on the conjunctival and nasal mucosa as it can be demonstrated in tear fluid and nasal secretions (Sakata et al., 1997; Innes et al., 2009). The prevalence of nonencapsulated pneumococci on mucosal surfaces compared to the almost complete absence of nonencapsulated pneumococci in invasive disease suggests nonencapsulated pneumococci possess resistance to important mucosal defences. Indeed, nonencapsulated pneumococci possess greater resistance to cationic antimicrobial peptides (the ∝-defensin human neutrophil protein 1–3) (Peschel, 2002; Beiter et al., 2008). The aim of this study was to investigate the effect of the presence of capsule on the in vitro pneumococcal resistance to extracellular human neutrophil elastase and Pomalidomide concentration cathepsin G. The in vitro bactericidal activities of elastase and cathepsin G were determined as described previously (Standish & Weiser, 2009). In brief, original cultures of pneumococcal wild-type strains and nonencapsulated derivatives (wild-type strain D39 (serotype 2), TIGR4 (serotype 4) and G54 (serotype 19F) and isogenic nonencapsulated derivatives) (Bootsma et al., 2007), were grown to mid-log in tryptic soy broth (TSB) at 37 °C, 5% CO2 without agitation, washed twice in PBS, and then ~ 107 CFU/mL S. pneumoniae were incubated in the presence or absence (control) of purified human 3.39 μM neutrophil elastase (NE; Calbiochem Cat. No. 324681) and 2.

Sequencing of hotspot mutations and fluorescence in situ hybridiz

Sequencing of hotspot mutations and fluorescence in situ hybridization of relevant genes were undertaken. Median age at diagnosis of six patients was 7.6 years. Tumours originated in the cerebral cortex (n = 2) or diencephalon (n = 4). Three patients presented with acute, PD98059 manufacturer massive haemorrhage and three had leptomeningeal dissemination at diagnosis. Paediatric e-GB had the typical histological characteristics seen in adult tumours. Universal immunoreactivity for INI1 and lack of diverse protein expression

were seen in all cases. One tumour had a chromosome 22q loss. Three tumours (50%) harboured a BRAF: p.V600E. One thalamic tumour had an H3F3A p.K27M. All patients received radiation therapy with (n = 3) or without chemotherapy (n = 3). All patients experienced tumour

progression with a median survival of 169 days. One patient with nonmetastatic disease had early leptomeningeal progression. Two patients had symptomatic tumour spread outside the central nervous system (CNS) through a ventriculoperitoneal shunt. One additional patient had widespread metastases outside the CNS identified at autopsy. Paediatric e-GBs are rare cancers with an aggressive behaviour that share this website histological and genetic characteristics with their adult counterparts. BRAF inhibition is a potential treatment for these tumours. “
“Nogo-A belongs to the reticulon protein family and is expressed in the inner and outer loops of myelin sheaths of oligodendrocytes. We analyzed the patterns of Nogo-A expression in human gliomas

in an effort to identify a useful marker for the characterization of oligodendroglial tumors. We determined the expression of Nogo-A in a panel of 58 astrocytic and oligodendroglial tumors using immunohistochemistry and compared the expression of Nogo-A with Olig-2, a recently identified marker for oligodendrogliomas. To localize Nogo-A expression, immunofluorescent staining was performed using other glial markers (MAP-2 and GFAP). Ceramide glucosyltransferase We also confirmed the overexpression of the Nogo-A protein in 53 astrocytic and oligodendroglial tumors using Western blot analysis. Based on immunohistochemical analysis, Nogo-A and Olig-2 had specificity in the detection of oligodendroglial tumors from astrocytic tumors (P = 0.001). The level of Nogo-A staining was highly correlated with Olig-2 (P = 0.001). The sensitivity and specificity of Nogo-A for oligodendroglial tumors was 86.9% and 57.1%, respectively. Nogo-A expression overlapped that of other oligodendroglial markers, but with different patterns of expression. Western blot analysis revealed that Nogo-A is predominantly expressed in 85.7% of oligodendroglioma cells and 93.7% of anaplastic oligodendroglioma cells.

Inguinal lymphocele nonresponsive to conservative treatment can b

Inguinal lymphocele nonresponsive to conservative treatment can be advantageously studied by LS and successfully treated by microsurgical reconstructive procedures, above all if associated to LL. © 2013 Wiley Periodicals, Inc. Microsurgery 34:10–13, 2014. Groin lymphocele (GL) is an important complication after inguinal lymph node dissection, for skin melanoma, vulvar cancer, and venous surgery,

with an incidence varying from 1.3 to 18.9%.[1-3] Conservative resolution is possible through check details several needle aspirations and compression bandaging, but it usually takes several months to show the risk of infections and other late complications. Recently, the use of intraoperative Isosulfan Blue,[4] modified technique of radical inguinal lymphadenectomy[5]and laparoscopic lymphnode resection,[6] have reduced the incidence of postoperative lymphatic morbidities such as wound dehiscence, infections, lymphorrhoea, and lymphedema. However, the incidence of lymphocele remains significant.[7] Nonoperative treatment of lymphocele arising from lymphatics injured during groin dissection

is not rarely unsuccessful. Different surgical BMS-777607 manufacturer methods have been proposed,[8] but all involve the closure of lymphatics merging at the lymphocele, increasing the risk of postoperative lower limb lymphedema or of worsening lymphedema if already clinically evident. In this report, we assessed the efficacy of a diagnostic and therapeutic protocol to manage inguinal lymphocele using lymphoscintigraphy (LS) and microsurgical procedures. Sixteen patients with unilateral GL were included in this report. Lymphocele was present for a mean period of 5.7 months (3–8 months) before surgical treatment. None of the patients had responded to

conservative treatment, including needle aspiration, sclerosing therapy, and compression. Infection occurred in three patients, with lymphangitis and fever. The mean age of the patients was 53.4 years (42–63 years). The size of lymphoceles varied from 7 to 12 cm in diameter. Seven of them presented also clinically evident leg lymphedema (LL) at the same side of the lymphocele. All of them had been previously treated nonoperatively by needle aspiration, ZD1839 ic50 sclerosing agents, and compression bandaging without healing of the pathology and relapse of lymphocele. Diagnostic investigations included venous ultrasound and superficial and deep LS of lower limbs. The patients’ information is shown in Table 1. To quantify visual findings in LS, the Kleinhans transport index (T.I.) was used. In this index, five parameters describe the lymph flow: lymphatic transport kinetics (K), distribution pattern (D), time lapse to appearance of lymph nodes (T in minutes, multiplied by 0.04), assessment of lymph nodes (N), and assessment of lymph vessels (V).

They are considered to be important targets for

They are considered to be important targets for Trametinib molecular weight tumor immunotherapy not only because of their different expression

patterns in healthy and transformed human tissues, but also because of their suppressive effect on immune system functions [2, 3]. In particular, N-glycolylated gangliosides are attractive targets for tumor immunotherapy because they are not normally synthesized in human tissues. This is due to a 92 bp deletion in the gene that encodes the cytidine-monophosphate-N-acetyl-neuraminc acid hydroxylase (CMAH) enzyme that catalyzes the conversion of N-acetyl to N-glycolyl sialic acid (NeuGc) [4-6]. Although humans lack this catalytic enzyme, studies have reported the presence of NeuGc in human tumors [7-10] and, in smaller amounts, in healthy adult human tissues [11]. Since an alternative pathway for NeuGc biosynthesis has not been described, the most accepted explanation for this phenomenon is the incorporation of NeuGc from dietary sources such as red meats and milk products. This incorporation occurs preferentially in tumor cells and may be due to the high division rate characteristic of tumor cells [11]. An additional proposed mechanism is that hypoxia present in the tumor microenvironment induces the BIBW2992 cell line expression of a sialin transporter in tumor cells resulting in enhanced incorporation

of (N-glycolylneuraminyl)-lactosylceramide (NeuGcGM3) [12, 13]. We have previously reported the induction of a high-titer antibody response against NeuGc-gangliosides in melanoma, breast, small, and non-small cell lung cancer (NSCLC) patients vaccinated with the mimetic anti-idiotypic antibody 1E10 [14-17]. One of these studies, performed in NSCLC patients, showed that the anti-NeuGcGM3 antibodies actively elicited by 1E10 vaccination were able Benzatropine not only to recognize NeuGcGM3-expressing tumor cells but also to induce their death by an oncotic necrosis mechanism, independent of complement activation [18]. Furthermore, there was a correlation between the induction of antibodies against NeuGcGM3 and longer survival times [17]. Surprisingly, this

idiotypic vaccination also elicited a “parallel set” of antibodies that recognize NeuGcGM3 and share the cytotoxic capacity against tumor cell lines but do not recognize 1E10 mAb. This suggested that this vaccination was activating a natural response against NeuGcGM3 ganglioside [15, 17]. Taking this into account, we wondered whether this cytotoxic anti-NeuGcGM3 response was present in healthy individuals. We show here that healthy humans possess antibodies against NeuGcGM3 ganglioside able to recognize and kill tumor cells expressing this antigen. These antibodies induce tumor cell death not only by complement activation, but also by a complement independent, oncotic necrosis mechanism, similar to the one observed in cancer patients treated with 1E10 mAb.