A strategy for a successful hookworm vaccine may use a cocktail o

A strategy for a successful hookworm vaccine may use a cocktail of potential vaccine candidates, including APR-1, targeting both the larval and blood-feeding stages (63). In the early 1990s, gastroenterologist John Croese and medical parasitologist Paul Prociv identified a series of cases of eosinophilic gastroenteritis in Caucasian residents of North Queensland LDE225 (69). Initially, the disease was of unknown

aetiology but as more cases were diagnosed, solitary adult hookworms were identified from a few patients and were subsequently identified as the canine hookworm, A. caninum, a parasite that was previously thought not to reach maturity in the human gut (69) (Figure 2). As awareness spread amongst clinicians, cases were diagnosed in other areas where A. caninum was prevalent, including southern Queensland (70) and the south of the USA (71). While solitary adult A. caninum were identified find more in only a handful of patients, infection was suspected

in many more, so we developed assays to detect circulating IgG and IgE antibodies to adult A. caninum excretory/secretory proteins and confirmed that many of the suspected cases of eosinophilic gastroenteritis where there was no parasitologic evidence of infection (i.e. no detection of adult worms or faecal eggs) were likely caused by occult infection with A. caninum (70,72). It is also noteworthy that in at least one patient, an adult A. caninum was observed in the absence of any overt pathology Rolziracetam or symptoms

(70). These findings pose an intriguing scenario whereby human enteric infection with the zoonotic A. caninum might be far more common than appreciated, and many of these infections might go unnoticed because of mild to no detectable pathology/symptoms. The Hygiene Hypothesis states that as populations become more hygienic and therefore virtually eliminate childhood parasitic infections (which have been constant partners through human evolution), there has been a concurrent increase in immune dysregulatory syndromes, such as autoimmunity, allergy and inflammatory bowel diseases. Diseases such as these are substantially less common in parts of the world with high helminth endemicity, and within endemic areas, the prevalence of allergic atopy is significantly lower in individuals with chronic worm infections (73–78). In epidemiologic studies, there is a good case for hookworm infection suppressing immune dysregulation.

The system consists of germline-encoded genes, i e toll-like rec

The system consists of germline-encoded genes, i.e. toll-like receptors (TLRs) 2, complements 3 and lectins 4, which are pattern recognition receptors (PRRs) that discriminate self from pathogen-associated molecular patterns 5. Dendritic cells (DCs) and macrophages (Mϕ) express a variety of PRRs that play important roles in both the innate and adaptive immune responses. Recent reports revealed that TLRs on DCs and Mϕ are involved in sensing various components of pathogens 2, giving rise to cellular inflammatory reactions. C-type

lectin receptors (CLRs) on GDC-0449 concentration DCs and Mϕ also sense pathogens 4. CLRs interact with various kinds of pathogens via carbohydrate recognition domains (CRD), which lead to internalization, degradation and subsequent antigen presentation. In addition, simultaneous triggering of a different set of PRRs has been shown to induce diverse innate immune responses. Much interest has been focused on type II transmembrane CLRs containing a single CRD. Dectin-1 6 and human (h) DC-SIGN (CD209) 7 are the most extensively studied members of this family. Dectin-1 is a major receptor for β-glucan 8, a component of the selleck products cell wall of Candida albicans, Pneumocystis carinii and Aspergillus fumigatus8–12. Microbe-mediated stimulation of Dectin-1 results in cellular oxidative burst and cytokine production through its ITAM and the Syk kinase pathway 13, 14. In addition, Dectin-1 has been shown

to function collaboratively with TLR2 to stimulate cytokine production 15 and Th17/Treg induction 16. hDC-SIGN recognizes mannose and fucose moieties in the

surface of a variety of microbes and viruses, such as Mycobacteria, Leishmania, Salmonella, Candida species, HIV, HCV, dengue virus, CMV, Ebola virus and Sindbis virus (refer to 17). However, pathogens, i.e. HIV and HCV, have however also found ways to subvert and use hDC-SIGN to their advantage 18, 19. Mycobacterium tuberculosis and HIV also target hDC-SIGN in order to upregulate DC production of the immunosuppressive cytokine IL-10 through Raf-1 kinase activation, which induces acetylation of the NF-κB p65 subunit in the presence of co-signaling from TLR4 20. Mice have eight hDC-SIGN homologues 21, 22. One of these homologues, SIGNR1, has been shown to be expressed on particular Mϕ subsets in the marginal zone of the spleen, medulla of the lymph nodes and the peritoneal cavity 23–25 and to possess mannose-binding activities like hDC-SIGN. SIGNR1 recognizes not only various polysaccharides, such as dextran and mannan, but also lipopolysaccharides (LPS) from Gram-negative bacteria (E. coli and Salmonella typhimurium) 23. The physical association of SIGNR1 with the TLR4-MD-2 complex on the cell surface accelerates TLR4 oligomerization upon recognition of the non-reductive end of LPS core on Gram-negative bacteria 26. In addition, SIGNR1 on resident peritoneal macrophages (rpMϕ) and SIGNR1-transfected RAW264.7 cells recognizes zymosan and heat-killed (HK) C.

Results: The model provided an excellent quality of ultrasound im

Results: The model provided an excellent quality of ultrasound images and technique replication for US guided biopsy. Trainees reported a high level of satisfaction with the simulation program, particularly increased confidence in handling the transducer and biopsy gun and reduced anxiety about procedural complications. Conclusions: Our simulation model for educating nephrology trainees in ultrasound-guided renal biopsy is easy and inexpensive to construct, satisfactorily

mimics human tissue density, and promotes confidence among trainees. This model could be used more widely in registrar training, and its potential impact on adverse outcomes from renal biopsies warrants further investigation. 225 LEUKOCYTE CHEMOTACTIC FACTOR 2 (LECT2) AMYLOIDOSIS IN FIRST NATIONS PEOPLE

IN BRITISH COLUMBIA, Vemurafenib CANADA: A CASE SERIES H HUTTON1, M DEMARCO2, A MAGIL2, P TAYLOR3 1Department Palbociclib order of Nephrology, University of British Columbia, Vancouver, BC; 2Department of Pathology, St Paul’s Hospital, Vancouver, BC; 3Department of Nephrology, St Paul’s Hospital, Vancouver, BC, Canada Background: Leukocyte chemotactic factor 2 (LECT2) amyloidosis is a form of amyloidosis which was first identified in 2008. It is emerging as a relatively frequent type of amyloid in cases which were previously unable to be classified by immunohistochemistry. Previously reported case series indicate that LECT2 amyloid is typically renal limited. Its distinctive morphological features are of intense Congo Red staining, and deposition in the renal interstitium and vasculature as well

as glomeruli. Two previously published case series from the United States describe a higher frequency of this condition in the Hispanic population. PAK5 Case Report: Four cases of renal LECT2 amyloidosis have been diagnosed in First Nations people in Northern British Columbia, Canada over the past four years. Mass spectrometry techniques were used to make the diagnosis. All presented with slowly progressive renal impairment and minimal proteinuria, and had typical biopsy findings. Conclusions: Our centre’s experience in finding this disease exclusively in First Nations people in a particular geographic location adds weight to a hypothesis that there is an as yet unknown genetic factor which underlies the pathogenesis of this disease. The lack of extra renal manifestations or significant proteinuria mean that LECT2 amyloid is likely to be an underdiagnosed cause of chronic kidney disease. The prevalence of LECT2 amyloid in Australia is unknown, and knowledge of this condition may aid appropriate further testing in Australian patients with renal amyloidosis which previously eluded specific classification.

Background: Indigenous Australians experience significantly worse

Background: Indigenous Australians experience significantly worse graft and patient outcomes following kidney transplantation compared with non-Indigenous Australians. It is unclear whether residential learn more location might contribute to this. Methods: This study involved all adult patients from the ANZDATA registry who received a kidney transplant in Australia between January 1st 2000 and December 31st 2012. Patients’ residential locations were classified as urban (major city + inner regional) or rural (outer regional–very remote)

using the Australian Bureau of Statistics Remoteness Area Classification. Results: Of 7,826 kidney transplant recipients, 271 (3%) were Indigenous. Sixty three percent of Indigenous Australians lived in rural locations compared with 10% of non-Indigenous (P < 0.001). In adjusted analyses, the hazard ratio (HR) for graft loss for Indigenous compared with non-indigenous was 1.67 (95% CI 1.04–2.65, P = 0.031). Residential location was not associated with graft survival (HR 1.19, 95% CI 0.95–1.48, P = 0.12). Both Indigenous race and residential location influenced patient survival, with an adjusted HR for death of 1.94 (95% CI 1.23–3.05, P = 0.004) comparing Indigenous with non-indigenous and 1.26

(95% CI 1.01–1.58, P = 0.043) comparing rural with urban recipients. Five-year graft and patient survival were 70% (95%CI 60–78%) and 69% (95%CI 61–76%) in rural Indigenous recipients compared with 91% (95%CI 90–92%) selleck screening library and 92% (95%CI 91–93%) in urban non-Indigenous recipients. Conclusions: Indigenous kidney transplant

Grape seed extract recipients experience worse patient and graft survival compared with non-Indigenous recipients, while rural residential location is associated with patient but not graft survival. Of all groups, Indigenous recipients residing in rural locations experienced the lowest 5-year graft and patient survival. 272 RENAL TRANSPLANTATION IN NEW ZEALAND MĀORI AND PACIFIC PEOPLE: AUSTRALIA AND NEW ZEALAND B GRACE1,2, T KARA1,2, S McDONALD2,3 1ANZDATA Registry, Adelaide, South Australia; 2University of Adelaide, South Australia, Australia; 3Starship Children’s Hospital, Auckland, New Zealand Aim: To compare incidence of RRT, deceased organ donation rates, transplantation rates and outcomes in Māori and Pacific people between Australia and New Zealand. Background: Associations between country of residence and incidence and treatment for ESKD are not known for these groups. Methods: RRT patient and deceased donor records were extracted from ANZDATA and ANZOD registries for 2000–2012. Populations were derived from StatsNZ and Australian Bureau of Statistics.

[3] Rarely, Cunninghamella bertholletiae, Rhizomucor pusillus and

[3] Rarely, Cunninghamella bertholletiae, Rhizomucor pusillus and Rhizopus microsporus can also initiate infections in immunocompetent individuals.[52, 54, 55] Many uncommon species have also been implicated in infections in India. Rhizopus homothallicus has been reported compound screening assay for the first time from patients with cavitary pulmonary mucormycosis.[56] Mucor irregularis, that was initially considered to be

involved in an emerging endemic cutaneous mucormycosis limited to China, has been reported from a case of rhino-facial mucormycosis in India.[57] Recently, a new mucoralean fungus, Thamnostylum lucknowense has been isolated from a patient with rhino-orbital mucormycosis.[58] The epidemiology of mucormycosis in India is intriguing, and varies significantly from the developed nations. The estimated number of cases in India seems to be alarmingly high, with uncontrolled diabetes being the most important risk factor. Certain confounding factors like renal failure and hepatic diseases have also been detected along with diabetes in mucormycosis patients; a detailed multicentric study is therefore warranted to precisely determine the association of diabetes with this invasive mycosis in India. ROC form remains the most common clinical presentation, albeit due to its association with diabetes. Isolated renal mucormycosis amongst immunocompetent, young individuals

is an emerging entity in India. Although isolated renal infections have been reported from China as well, but the MAPK inhibitor Baf-A1 chemical structure majority of patients in China have pre-disposing risk factors for developing mucormycosis, except the paediatric population. The disease is highly aggressive but the mode of acquisition and spread of the fungus through the body are not yet

known, and demand urgent investigation. Cutaneous infections in apparently healthy individuals due to traumatic implantation of Apophysomyces elegans are also a common finding in India, although uncommon in other countries. The precise ecology, epidemiology and taxonomy of this fungus are not well understood, and further studies on these aspects would provide valuable insights into the presence of mucoralean agents in environment, the susceptible hosts and the mode of fungal acquisition and spread. The position of RS is supported by funding from Council of Scientific and Industrial Research (CSIR), Govt. of India in the form of Senior Research Associateship (Scientists’ pool scheme). None. “
“The ability of Candida albicans to form biofilms on denture surfaces is a significant cofactor in the pathogenesis of denture stomatitis. In this study, we applied a differential staining approach and scanning electron microscopy (SEM) to analyse the effect of sodium hypochlorite and chlorhexidine gluconate on the viability, removal and morphology of C. albicans forming biofilms on denture acrylic using an in vitro model. Immediately after treatment, to distinguish live from dead C.

[40, 41] The dependence of both human and murine macrophages on N

[40, 41] The dependence of both human and murine macrophages on NO to control the pathogenesis of mycobacteria inside the host suggests that adequate activation of macrophages to produce this free radical is critical for host defence. In the present study, we demonstrated that IL-17A synergistically enhanced NO production and iNOS expression in BCG-infected macrophages in dose- and time-dependent manners. Kinetics study revealed that IL-17A enhanced iNOS expression at early time-points after BCG infection. Incubation of IL-17A did not further enhance iNOS expression in macrophages after 24 hr of BCG infection (Fig. 1c). Such observation can

be explained by negative feedback regulation on iNOS to prevent over-production of NO.[28, 29] Under the conditions we have tested, we observed that IL-17A

alone did not induce detectable levels of iNOS protein and NO production in macrophages. Our data suggest that IL-17A is able to prime selleck chemicals macrophages to produce NO in response to mycobacterial infection. Similar observations have been reported by Kawanokuchi et al.[42] – that IL-17A is able to enhance both iNOS expression and NO production in lipopolysaccharide-stimulated microglia, whereas IL-17A by itself has no effect on either product. In another study, IL-17A has been shown to induce iNOS expression and NO production in articular chondrocytes.[43] see more Interleukin-17A also induces NO production in cartilage explants from osteoarthritis patients.[44] The differences between observations among these studies may implicate differential effects of IL-17A on NO production in specific cell types. Binding of the cell wall components (e.g. lipoarabinomannan and peptidoglycan) and secretory proteins (e.g. 38 000 molecular weight glycolipoprotein) of mycobacteria to Toll-like receptor 2 triggers the activation of multiple MAPKs in macrophages.[15, 45, 46] Consistent with our previous studies,[19, 21, 23] our results demonstrated that BCG is able to induce the phosphorylation of JNK, ERK1/2 and p38 MAPK and also translocation

of NF-κB p65 in macrophages. Our results revealed that IL-17A specifically enhanced BCG-induced phosphorylation of JNK in macrophages. Neither BCG-induced phosphorylation of ERK1/2 nor p38 MAPK was affected by IL-17A. 5 FU Moreover, our data suggest that the enhanced iNOS expression in IL-17A-pre-treated, BCG-infected macrophages can be explained by enhanced iNOS mRNA stability in these macrophages. Korhonen et al.[27] showed that cytokine-induced iNOS mRNA can be stabilized by a JNK signalling pathway through a tristetraprolin-dependent mechanism. The study may provide insights into the mechanism regarding our finding that IL-17A can enhance the stability of BCG-induced iNOS mRNA. Although our data indicate that NF-κB is not involved in IL-17A-enhanced iNOS expression in BCG-infected macrophages, other activated transcription factors may have been involved.

H2O2 and known reactive oxygen species inducers,

lipopoly

H2O2 and known reactive oxygen species inducers,

lipopolysaccharide (LPS) and tumour necrosis factor-α (TNF-α) enhanced CK2 activity, phosphorylation and protein expression, which was again inhibited by antioxidant. PAF, LPS and TNF-α induced increased CK2 activity, phosphorylationand protein expression, which were inhibited by p38 inhibitor. PAF, LPS or TNF-α increased pulmonary metastasis of B16F10, which was inhibited by antioxidants, CK2 inhibitor and p38 inhibitor. Our data suggest that (i) CP-690550 order reactive oxygen species activate CK2 via p38, which, in turn, induces NF-κB activation, and (ii) PAF, LPS and TNF-α increase pulmonary tumour metastasis via the induction of the reactive oxygen species (ROS)/p38/CK2/NF-κB pathway. “
“Immunotherapy using dendritic cells (DC) has shown promising results. However, the use of an appropriate DC population is critical for the outcome of this treatment, and the search for an optimal DC subset is still ongoing. The DC used in immunotherapy today are usually matured with a cytokine cocktail consisting of TNF-α, IL-1β, IL-6 and PGE2. These cells have deficits in their cytokine production, particularly IL-12p70, mainly because of the presence of PGE2. Bromelain is a pineapple stem extract containing a mixture of proteases that GW-572016 in vivo has been used clinically in adjuvant cancer treatment. In this

study, we analysed the effect of bromelain on human monocyte-derived DC. We added bromelain to the cytokine cocktail and modified cytokine cocktails with either no PGE2 or reduced amounts of PGE2, respectively. Combining bromelain with the cytokine cocktails containing PGE2 resulted in an increased surface expression of CD83, CD80 and CD86. The chemokine receptor CCR7 was also considerably upregulated in these DC populations compared with DC treated with the cytokine cocktail alone. Removal or reduction of PGE2 from the cytokine cocktail

did not increase the IL-12p70 secretion from stimulated DC, and addition of bromelain to the different cytokine cocktails resulted in only a minor increase in IL-12p70 production. Moreover, combining bromelain with the cytokine cocktails did not improve www.selleck.co.jp/products/Romidepsin-FK228.html the T cell stimulatory capacity of the generated DC populations. In conclusion, bromelain treatment of monocyte-derived DC does not improve the functional quality compared with the standard cytokine cocktail. Dendritic cells (DC) are professional antigen-presenting cells with the unique ability to stimulate naïve T cells [1]. Immature DC circulate in our bodies constantly sampling the surroundings for potential antigens. Upon encounter with an antigen in the presence of danger signals, DC start to mature and migrate toward the lymph node to present the captured antigens to T cells.

, 2006) and a protein vaccine recombinant urease B (rUreB) based

, 2006) and a protein vaccine recombinant urease B (rUreB) based on the full-length urease B (Béguéet al., 2007). Our work showed that the DNA vaccine was not immunogenic, while rUreB was highly immunogenic, and that the prime-boost approach with either rUreB followed by the DNA vaccine or the reverse did not confer any additional benefit (Béguéet al., 2007). We also showed that rUreB was immunogenic when administered percutaneously but not by mucosal immunization, and that aluminum hydroxide significantly increased the immunogenicity of rUreB alone (Bégué & Moll, 2009). As aluminum hydroxide is an adjuvant accepted for use in human immunization, we then proceeded to evaluate the Palbociclib in vivo protective efficacy

of rUreB plus aluminum hydroxide against H. pylori infection and compared with other approaches we had found immunogenic. The this website results are reported here. rUreB was prepared as described previously (Béguéet al., 2007). Genomic H. pylori DNA (ATCC 43504D, Manassas, VA) was used as template to PCR-amplify the full-length ureB gene (GenBank AF352376; 1–1710 bp) and cloned into the SalI site of the pQE9 vector (Qiagen, Valencia,

CA). Competent XL10Gold E. coli cells were transformed and protein expression was induced with 1 mmol L−1 isopropyl-β-d-thiogalactopyranoside. Cells were lysed with 8 mol L−1 urea buffer (pH 8.0) and rUreB was purified by (His)6-tag affinity in a nickel column (Ni-NTA Superflow Column, Qiagen). The product was dialyzed to phosphate-buffered saline

(PBS, pH 7.4) and concentrated to 1 μg μL−1. Three different adjuvants were used in the experiment: CpG ODN 1826 (5′-tcc atg acg ttc ctg acg tt-3′) suspended in PBS to a concentration of 1 μg μL−1; aluminum hydroxide [Al(OH)3 3%, Alhydrogel, Brenntag Biosector, Frederikssund, Denmark] mixed with an equal volume of rUreB and incubated overnight at 4 °C for absorption; and Freund’s adjuvant (Sigma-Aldrich, St. Louis, MO), complete for first immunization and incomplete for subsequent ones. Six-week-old female BALB/c mice (Harlan Sprague, Dawley, Indianapolis, IN), Tolmetin five per group, were immunized either intranasally (40 μL rUreB plus 10 μL CpG), intramuscularly (50 μL rUreB plus 50 μL aluminum hydroxide) or subcutaneously (25 μL rUreB plus 25 μL Freund’s adjuvant) three times (weeks 0, 2 and 6). Control mice received no immunization. Before immunization and 2 weeks after the third dose, stool (two pellets) and blood (100 μL) were obtained from each animal to determine immunogenicity. Stools were suspended in 100 μL PBS, vortexed, centrifuged and the supernatant was collected; blood was centrifuged and serum was collected. Anti-urease B antibodies were determined by an enzyme-linked immunosorbent assay using rUreB expressed in Saccharomyces cerevisiae as the capture antigen (Béguéet al., 2007). Yeast-derived rUreB (0.

While our custom-designed

While our custom-designed RXDX-106 datasheet array included 998 sites from the X chromosome and several thousand sites

from autosomal chromosomes, only X chromosome sites were found to be consistently hypermethylated (n = 18) or hypomethylated (n = 25) in twins with SSc while sharing identical methylation profiles in the one set concordant for the disease. These sites corresponded to 26 genes that were investigated further for their function and their putative pathways involved; such genes could be expected to be expressed differentially based on their methylation profile although an inverse correlation between hypermethylation and reduced expression can only be hypothesized and should be investigated by reverse transcription–polymerase chain reaction (RT–PCR) in the future if additional blood samples can be obtained for this purpose. Among differentially

methylated selleckchem sites, we found some of particular interest. First, the spermine synthase (SMS) gene encodes for an enzyme involved in polyamine synthesis and recycling [39]. The synthesis is directed by two aminopropyltransferases, i.e. spermidine synthases converting putrescine into spermidine and SMS which converts spermidine into spermine, with decarboxylated S-adenosylmethionine (SAM) as the aminopropyl donor in both cases [40]. A ‘polyamine hypothesis’ has been proposed recently by Wesley Brooks, who

suggests that alterations in polyamine synthesis may lead to disease phenotype secondary to abnormalities in DNA methylation status when SAM is in excess [41]. Secondly, among hypomethylated sites, four refer to the gene encoding for DDX26B, a member of the DEAD/H-box helicases involved in various steps of RNA metabolism and chromatin dynamics [42,43], particularly in the Drosophila Meloxicam mode [44]. Of note, DDX proteins are involved in virus-induced innate immunity acting as a scaffold for protein–protein interactions in the signalling cascade that controls IFN type 1 [45] as a critical component of the TANK-binding kinase-1 that activates the transcription factor IFN regulatory factor (IRF)-1 and IRF-7 to promote the expression of IFN-α and -β[46]. Accordingly, changes in DDX3X expression mediated by altered methylation may support the correlation between viral infections and SSc [47]. Thirdly, the association between SSc and ENOX2 hypomethylation is of particular interest, as tissue hypoxia is a major feature of SSc tissues. ENOX2 is a membrane copper-containing enzyme that catalyzes electron transfer from hydroquinone or nicotinamide adenine dinucleotide (NADH) to molecular oxygen, thus playing a role in the induction of reactive oxygen species [48] which have a direct profibrogenic effects on fibroblasts, thus favouring fibrosis [49].

As will be discussed here, reproductive immunology is a very good

As will be discussed here, reproductive immunology is a very good example of how paradigms have shaped our understanding of immune regulation but don’t provide all of the answers. A central paradigm of modern

immunology is the clonal-selection theory, formulated by F. MacFarlane Burnet1 in the late 1950s, which explains how immune system makes antibody responses to diverse antigens and NU7441 discriminates self from non-self. The key features of the clonal-selection theory are that (i) each lymphocyte bears antigenic receptors of a single specificity; (ii) receptor specificity and diversity is germline-encoded, randomly generated and precedes antigen encounter; (iii) lymphocytes with receptors that recognize self-molecules are deleted at an early stage of development; and (iv) antigen encounter of mature lymphocytes leads to clonal expansion and consequently adaptive immunological memory. The clonal-selection theory has prompted

much debate and been BAY 57-1293 datasheet challenged as being over-simplified in its view of self–non-self discrimination by (among others) Polly Matzinger’s Danger model and Charles Janeway’s pathogenicity model.2 However, it is worth noting that Burnet made his discovery in an era prior to the development of all the transgenic and knock-out mice, molecular probes and monoclonal antibodies (moAbs) that now permit a more detailed dissection of the immune system and test the predictions of paradigms more fully. MacFarlane Burnet’s work was groundbreaking, and he shared the 1960 Nobel Prize for Medicine or Physiology with Peter Medawar for the discovery of immunological tolerance (http://nobelprize.org/nobel_prizes/medicine/laureates/). However, Peter Medawar was also among the first to recognize that a simple self–non-self model was not absolute in its predictions of immunological tolerance and immune activation, as it could not explain the phenomenon of mammalian

pregnancy Low-density-lipoprotein receptor kinase in the face of a functional maternal immune system. Medawar3 formulated three hypotheses that could help explain placentation and mammalian reproduction within the context of self–non-self discrimination. These hypotheses formed the basis of three new paradigms of reproductive immunology, namely that (i) the maternal immune system is suppressed; (ii) the placenta acts a barrier between the mother and foetus; and (iii) the foetus is antigenically immature and therefore not recognized by the maternal immune system. The status of these paradigms was eloquently reviewed by David Billington4 in 2003 to mark the 50th anniversary of Medawar’s publication. With better immunological tools, we now know that Medawar’s paradigms were over-simplified, with the exception of the importance of anatomical separation of the mother and foetus by the placenta. However, like other important paradigms, they fuelled key discoveries in reproductive immunology and in turn have led to the formulation of modified and new paradigms.