Thus, in Australia and New Zealand in 2005, live donor transplants accounted for 41% of the total transplants performed.

In comparison, although the number of deceased donor transplants performed was similar 10 years earlier in 1995 (348 in Australia and 70 in New Zealand), fewer live donor transplants were performed (94 in Australia and 24 in New Zealand), thus in 1995, live donor transplants accounted for only 22% of the total transplants performed.1 This progressive increase in the number of live donor transplants performed is indicative of the overall success of kidney transplantation as well as the increased confidence in using live donors. However, it also reflects the continued shortage of deceased donor organs. Since 2000, 12-month primary MI-503 deceased donor recipient

survival in Australia and New Zealand has been approximately 96%, and 12-month primary deceased donor graft survival has been approximately 92%.1 In comparison, 12-month primary https://www.selleckchem.com/products/Tigecycline.html live donor recipient survival has been approximately 99%, and 12-month primary live donor graft survival has been approximately 96%.1 Examining longer term results: recent 5-year primary deceased donor recipient survival has been approximately 87%, with 5-year primary deceased donor graft survival being approximately 80%. In comparison, 5-year live donor recipient survival has been approximately 94%, with 5-year live donor graft survival being approximately 86%. These recipient and graft survival outcomes for both deceased and live donation are excellent. Unadjusted figures show superior outcomes for live donor transplantation relative to deceased donor transplantation. Various studies have assessed the success of live donor kidney transplantation relative to the donor source (e.g. related, unrelated, spousal). In general, graft survival is excellent and equivalent regardless of whether the donor is related or

unrelated.2–5 Phosphoglycerate kinase Unmatched, unrelated live donor transplants show similar or superior results compared with deceased donor transplants.2–5 Gjertson and Cecka analyzed United Network for Organ Sharing (UNOS) Registry data and found that 5-year graft survival rates for spousal, living unrelated and parental donation were all similar (75%, 72% and 74%, respectively).5 Graft half-lives were 14, 13 and 12 years, respectively.5 Mandal et al. analyzed USRDS data and compared primary deceased donor versus primary live donor transplantation for different age groups.6 The outcomes for recipients aged over 60 years (n = 5,142) demonstrated that live donation was always associated with a better outcome. Comparing deceased donor with live donor renal transplant in this older age group, the relative risk of death was 1.72 and the relative risk of graft failure was 1.64. Living donor renal transplantation for recipients aged 18–59 years was also generally associated with better outcomes compared with deceased donor renal transplantation.

It can be excluded that surface opsonisation represents a major reason for the elimination of C3 and C1q from CSF since such a mechanism would not explain the generation of fragments of C1q, which is not cleaved during complement activation. Although the complement protein C3 is cleaved during complement activation, this mechanism cannot be responsible for the appearance of large fragments in the supernatant as visible by Western blotting, since but

only very small C3-derived peptides are soluble, all larger parts of the molecule remain attached to the pathogen surface. Second, the hypothesis of proteolytic complement degradation selleck compound is strongly supported by an additional experiment: after growth, the culture supernatants of various Pseudallescheria

and Scedosporium isolates were separated from the fungal hyphae by filtration; these supernatants were supplemented with purified C1q or C3 proteins. Napabucasin clinical trial Again, a time-dependent elimination of the purified complement proteins could be observed for the fast-degrading isolates with appearance of larger fragments after incubation of up to 2 days, which are then progressively disappear over time (data not shown). Third, Pseudallescheria and Scedosporium isolates were grown in nutrient-rich Sabouraud medium that makes the secretion of proteolytic enzymes for nutrient gaining dispensable, as shown for Aspergillus species.27,30 These fungal Sabouraud supernatants did not induce any decrease in the concentration of supplemented complement proteins. In summary, we hypothesise that the ability to deal with the possible effects

of complement proteins has a phylogenetic background and is largely species-specific. The predilection of infecting the CNS could have favoured the evolution of enzyme systems for degrading C3 and C1q. Furthermore, our results support the theory that – depending on the taxonomy – different species can be supposed to develop and exploit various mechanisms that facilitate growth and survival in the host and in specific organs. To identify these additional mechanisms in the different Pseudallescheria/Scedosporium species and to further examine the regulation of protease secretion remains an interesting topic for further investigations. All contributing authors declare that there are no conflicts of interest. “
“Candidemia is an important cause of morbidity and mortality Ribonucleotide reductase in the healthcare setting. However, there is limited information about risk factors for such infection among elderly patients. A case–control study was conducted during the period 2008–2011. For each case, two controls were selected among patients admitted to the same hospital, and individually matched by sex, age, time of admission, hospital ward and hospitalisation duration. The adjusted odds ratio (OR) was calculated using multiple conditional logistic regression. We identified 145 episodes of candidemia occurring in 140 patients with a median age of 80 years.

Enhanced disease activity was accompanied by significantly increased transcription of IFN-γ, IL-12 and TNF-α mRNA in regional lymph nodes and spleen as well as by increased serum levels of IFN-γ. Furthermore, by blocking CXCR4, expression of the cell adhesion molecules ICAM-1 and VCAM-1 was upregulated on vascular endothelial cells of the sciatic nerve, which coincided with significantly increased infiltration of the sciatic nerve by CD4+ T cells and macrophages. Remarkably, combined antagonization of both CXCR4 and CXCR7 significantly suppressed disease activity. This was accompanied by increased frequencies of activated

and highly IFN-γ-expressing, P0106–125-specific T cells in regional lymph nodes and spleen; however, selleck products these cells were unable to infiltrate the sciatic nerve. These data suggest differential and hierarchically ordered roles for CXCR4/CXCL12- vs. CXCR7/CXCL12-dependent effects during EAN: CXCR7/CXCL12 interaction is a gatekeeper for pathogenic cells, regardless of their CXCR4/CXCL12-dependent state of activation. “
“F. Dehghani, MI-503 nmr M. Sayan, A. Conrad, J. Evers, C. Ghadban, R. Blaheta, H.-W. Korf and N. P. Hailer (2010) Neuropathology and Applied Neurobiology36, 598–611 Inhibition of microglial and astrocytic inflammatory responses by the immunosuppressant mycophenolate mofetil Aims: Nucleotide depletion induced by the immunosuppressant mycophenolate mofetil (MMF) has been shown to exert

neuroprotective effects. It remains unclear whether nucleotide depletion directly counteracts neuronal demise or whether it inhibits microglial

or astrocytic activation, thereby resulting in indirect neuroprotection. Methods: Effects of MMF on isolated microglial cells, astrocyte/microglial cell co-cultures and isolated hippocampal neurones were analysed by immunocytochemistry, quantitative morphometry, and elisa. Results: We found that: (i) MMF suppressed lipopolysaccharide-induced Baricitinib microglial secretion of interleukin-1β, tumour necrosis factor-α and nitric oxide; (ii) MMF suppressed lipopolysaccharide-induced astrocytic production of tumour necrosis factor-α but not of nitric oxide; (iii) MMF strongly inhibited proliferation of both microglial cells and astrocytes; (iv) MMF did not protect isolated hippocampal neurones from excitotoxic injury; and (v) effects of MMF on glial cells were reversed after treatment with guanosine. Conclusions: Nucleotide depletion induced by MMF inhibits microglial and astrocytic activation. Microglial and astrocytic proliferation is suppressed by MMF-induced inhibition of the salvage pathway enzyme inosine monophosphate dehydrogenase. The previously observed neuroprotection after MMF treatment seems to be indirectly mediated, making this compound an interesting immunosuppressant in the treatment of acute central nervous system lesions. “
“Neuronal and mixed neuronal-glial tumors of the CNS show a wide spectrum of components.

Despite an initial response to treatment, with her creatinine improving to 215 µmol/L, she progressed

to ESRF 6 months later after developing severe sepsis in the setting of diverticulitis RGFP966 concentration complicated by colonic perforation requiring a permanent colostomy. Her immunosuppression was ceased during her septic episode and then recommenced 9 months after her initial diagnosis. She received a further 6 months of Cyclophosphamide but remained on haemodialysis until the time of her transplantation. Her other relevant comorbidities included hypertension and recurrent urinary tract infections. MPO-ANCA titres remained persistently elevated at >200 RU/mL, when measured at four monthly intervals over the course of 5 years. However, she remained well on dialysis, with no systemic manifestations of vasculitis. Transplantation occurred in January 2011. She received a Complement-dependent cytotoxicity (CDC) T-cell crossmatch-negative cadaveric graft from a 49-year-old donor, with 5/6 Human leucocyte antigen (HLA) mismatch. Her CDC Panel reactive

antibody (PRA) was 25% peak, and 5% current. Immunosuppression consisted of Basiliximab induction (20 mg on days 1 and 4) and Tacrolimus, Mycophenolate Mofetil (2 g/day) and Prednisolone (20 mg/day) maintenance therapy. She had multiple class I selleck anti-HLA antibodies, but none were donor-specific. Her anti-MPO titre was >200 RU/mL at the time of transplantation. Her hospital course was uncomplicated, with a

serum creatinine of 140–150 µmol/L 2 weeks post-discharge. Five weeks post-transplant the combination of a slight rise in her serum creatinine to 160 µmol/L and microscopic haematuria with an elevated urinary protein creatinine ratio (0.11 g/mmol) next prompted an allograft biopsy. The histology was consistent with vasculitis in her allograft, with cellular crescents in 6/16 glomeruli, and segmental necrosis with fibrinoid change in seven glomeruli. There was no concurrent acute cellular or humoral rejection identified. Immunostaining for C4d, IgG, IgM, IgA, C1q were all negative (Fig. 1). She was treated with pulse Methylprednisolone (500 mg × 3), and increased maintenance Prednisolone (50 mg daily). Plasma exchange was instituted with seven exchanges at 60 mL/kg, using a mix of fresh frozen plasma and 4% albumin. Her Mycophenolate was ceased, and oral Cyclophosphamide commenced at 125 mg daily (2 mg/kg). Her Tacrolimus was continued, aiming for a trough level of 5–8 mg/L. She continued on Tacrolimus, Cyclophosphamide and Prednisolone for 3 months, at which time another biopsy was performed. Throughout this time, she remained clinically well, and her renal function improved to 120–130 µmol/L. Her anti-MPO titre remained high but fell with plasma exchange to a trough of 130 RU/mL. Repeat biopsy showed segmental areas of sclerosis and fibrosed crescents, with no indication of current vasculitis activity or allograft rejection.

Identification of T. mentagrophytes CDO provides indispensable tools for future studies of dermatophyte pathogenicity and development of new approaches for prevention and therapy. “
“This article reports a new case of protothecosis by Prototheca wickerhamii in goats. The animal presented severe respiratory difficulty and nodules, sometimes ulcerated, in the nasal vestibule, mucocutaneous junction of the nostrils and skin of the face. Prototheca wickerhamii was isolated from the lesions. The animal had no clinical or haematologiccl evidence of immunodepression. The

agent was highly resistant to antimicrobial drugs. The goat was treated unsuccessfully with fluconazole and euthanised 10 months after the diagnosis of the disease. Histological lesions find more were necrotising MK-8669 cost pyogranulomatous dermatitis, rhinitis and osteomyelitis with myriads of walled sporangia characteristic of P. wickerhamii. It is suggested that in goats, protothecosis is characterised by a chronic, slowly progressive infection, which affects immunologically competent goats, causing multifocal, ulcerative, pyogranulomatous and necrotising lesions of the mucosa of the nasal vestibule, mucocutaneous junctions of the nostrils and skin of the face. “
“Basidiobolus ranarum (Entomophthoromycotina) very rarely

affects the gastrointestinal (GI) tract. To date, reported paediatric GI basidiobolomycosis cases are 27 worldwide; 19 from Saudi Arabia and 8 from other parts of the world. Often these cases present a diagnostic dilemma, are prone to misdiagnosis and lack of disease confirmation by proper molecular methodologies. The fungal mass removed by surgery is usually sent for conciliar histopathology, isolation by fungal cultures and final molecular testing for basidiobolomycosis. The incidence of basidiobolomycoses, their predisposing factors and the molecular diagnosis of the fungus causing the disease in combination

with a phylogenetic framework are reviewed. Basidiobolomycosis is an unusual, rare fungal skin infection causing chronic subcutaneous zygomycosis.[1, 2] It is caused by Basidiobolus ranarum (Entomophthoromycotina)[3, 4] with human disease concentrated Casein kinase 1 in tropical and subtropical regions. Extracutaneous involvement is extremely rare[5] with gastrointestinal (GI) involvement being exceedingly rare[6-10]; with only 66 adult and 27 paediatric cases reported worldwide. Most adult cases, 19 patients, were from the United States of whom 17 [89%] were from Arizona[11]; whereas 14 patients were from Iran,[11] 12 patients from Iraq,[12] 11 from the Kingdom of Saudi Arabia (KSA)[11] and 4 from Brazil.[11] The remaining six patients were one from each of Nigeria, India, Bangladesh, Italy, Netherlands and one with unreported country of origin.[11] The 27 reported paediatric patients are summarised in Table 1,[12-24] where 19 patients are from KSA, 3 from Iran, 2 from Iraq, 2 from Brazil and 1 from Nigeria.

[33]. Cells were washed

three times in media and counted. PBMC from cutaneous leishmaniasis patients and non-infected individuals were used for in vitro culture TCR-usage analysis. Cultures were set up using a concentration of 2·5 × 105 cells in 96-well plates in the presence or absence of SLA (10 µg/ml final concentration) and were incubated for approximately 20 h. During the last 4 h of culture, Brefeldin-A (Sigma-Aldrich) (1 µg/ml), which impairs protein secretion by the Golgi complex, was added to the cultures. After the incubation period, cultures were harvested and submitted to flow cytometric analysis to evaluate T cell repertoire, surface markers and cytokine profile. The antibodies used for staining were immunoglobulin fluorescein isothiocyanate (FITC) and phycoerythrin (PE) controls (PharMingen, San selleck inhibitor Diego, CA, USA), anti-Vβ2-biot, anti-Vβ3-biot,

anti-Vβ5·1-biot, anti-Vβ5·2-biot, anti-Vβ11-biot, anti-Vβ17-biot, anti-Vβ 24-biot (Immunotech, Burlingame, CA, USA) anti-Vβ8-FITC, anti-Vβ 12-FITC (Immunotech), SA-FITC (PharMingen), anti-CD69 PE (Ebioscience, San Diego, CA, USA), Talazoparib anti-HLA-DR-PE, anti-CD45RO-PE (PharMingen) and anti-CD4-PE-Cy5 (Ebioscience). The anti-cytokines antibodies used were PE-labelled anti-IFN-γ, anti-TNF-α (PharMingen) and anti-IL-10 (Caltag, Carlsbad, CA, USA). PBMC were analysed for their repertoire, surface markers and intracellular cytokine expression pattern. Briefly, 2·5 × 105 PBMC were cultured in 96-well plates in

200 µl cultures for 20 h with either media alone or SLA (at 10 µg/ml final concentration). Brefeldin-A (1 µg/ml) was added during the last 4 h of culture to impair protein secretion, allowing for cytokine intracellular staining, as performed previously by us [11]. The cells were then stained for T cell receptor Vβ repertoire and surface markers, and fixed using 4% formaldehyde (Sigma-Aldrich). Cells were then permeabilized with a solution of saponin (Sigma-Aldrich) and stained, for 30 min at 4°C, using anti-cytokine monoclonal antibodies directly Etofibrate conjugated with PE. PE-labelled immunoglobulin control antibodies and a control of unstimulated PBMC were included in all experiments. Preparations were washed and fixed as described in the previous section and analysed using fluorescence activated cell sorter analysis (FACS), selecting the total lymphocyte population (Fig. 1). In all cases both cytokine and surface marker staining were associated with T cell receptor Vβ repertoire staining for studying the expression of cytokines and surface markers together and the phenotype of the cells that produced them. At least 40 000 gated events were acquired for later analysis.

Since S1P1 signalling leads to activation of STAT3 to drive Th17 responses,[54] it is possible that FTY720 treatment negatively impacts Th17 development, potentially decreasing Tcm cell numbers as well. The Tcm cells produce primarily IL-2 in response to T-cell receptor activation, which signals through STAT5, and promotes Tcm cell proliferation and differentiation into effector cells.[57] Pepper et al. suggest that, although Th17 cells are not likely

to enter the long-lived memory cell pool, IL-17-producing cells retain expression of CCR7, suggesting that these cells bear some features of Tcm cells.[62] Cytokines such as IL-2, IL-7 and IL-15 are needed for memory T-cell responses and maintenance of the memory cell pool.[57, click here 62,

63] All of these cytokines signal through downstream activation of STAT5, which can inhibit the generation of Th17 cells.[64] This may explain why Th17 cells do not persist in the memory pool. Memory T cells can also reside in non-lymphoid tissues[65] and can be rapidly mobilized to provide immunity in a range of tissues including the skin, small intestine, brain and salivary glands. These T resident memory (Trm) cells were uniformly positive for the activation marker CD69 and showed low expression of KLF2 and its target, S1p1r.[66] This expression pattern was temporally regulated based on time of residence in non-lymphoid tissue. Forced expression of KLF2 in CD8 T cells INK 128 in vivo resulted in increased S1P1 and decreased CD69, supporting previous findings. Forced expression of S1P1 in CD8 T cells that seeded the Trm cell pool prevented the establishment Obatoclax Mesylate (GX15-070) of Trm cell populations, implying that S1P1 is a negative regulator of Trm cell development. It is likely that the co-regulation of CD69 versus S1P1 surface expression is involved in maintaining

Trm cells in non-lymphoid tissues, much as they regulated lymphoid organ residency.[65, 67] S1P1 inhibition of TGF-β signals may also be involved in subpopulations of Trm cells, since expression of the Trm tissue retention integrin CD103 is induced by TGF-β. Since decreased expression of S1P1 is likely the key to settling of the Trm cell niche, modulation of TGF-β/CD103 by S1P1 in specific Trm cell subsets may affect retention signals. The S1P receptors are best known for their functions within the vasculature and for their effects on lymphocyte trafficking. Although these are important features of S1P/S1PR signalling, they are by no means the only settings where this system is active. Indeed, crucial roles for the S1P/S1P1 signalling axis in T lymphocyte activation and subset polarization are now being appreciated.[38, 53, 54] These effects on T-cell phenotype may function in concert with well-established S1P1 trafficking mechanisms to integrate location signals with activation cues in vivo, ensuring proper segregation to distinct sites for effective priming and induction of effector functions in response to infection.

The restriction to the manipulation of the immunoglobulin gene locus allows the dissection of B-cell versus T-cell contribution to the acute allergic phenotype. This new mouse strain allows active immunization experiments to sensitize for anaphylaxis induction. We believe this is closer to the dynamic in vivo situation in allergic patients where polyclonal or oligoclonal antibody responses of different antibody isotypes are induced.

The results presented here suggest that a strong antigen-specific polyclonal IgE response is most powerful in sensitizing both Hormones antagonist basophils and mast cells. Nevertheless, basophil-depletion experiments indicate that antigen-specific click here IgE on basophils plays an important role in the anaphylactic process in vivo. This view is indirectly supported by recent data that an IgE-specific hypersensitivity inhibiting molecule called Allergin-1, is expressed on

mast cells but not basophils [9]. Mast cells, however, do contribute to the anaphylactic reaction in vivo, since a partial anaphylactic drop in body temperature occurs even in basophil-depleted mice. Our data are in partial contrast to results, which suggested that basophil-dependent passive systemic anaphylaxis is IgG1 mediated, but not IgE mediated [9, 37]. The probable reason for this difference is that passive sensitization with monoclonal IgE is less efficient, due to the instability of IgE, compared with a polyclonal IgE antibody response. Recently, Fluorometholone Acetate Sawaguchi et al. showed that in a passive systemic anaphylaxis model, mast cell but not basophil depletion inhibited anaphylaxis [38]. In addition, Ohnmacht et al. [40] demonstrated for the Mcpt8Cre-basophil-deficient mouse model that

in active systemic anaphylaxis no difference between controls and the basophil-lacking mice exist. This does not contradict our data, because in the IgEwt/wt mice, where IgG1 levels dominate IgE, basophil depletion has only a minimal suppressive effect on anaphylaxis. This supports the hypothesis that basophils are dispensable for an IgG1-dominated anaphylaxis reaction [39]. Studies with novel basophil- or mast cell-deleted mouse strains have to be performed in order to elucidate the precise contribution of basophils versus mast cells in IgE-mediated active anaphylaxis [39, 40]. Further support for our model comes from experiments, which suggest that IgG-containing immune complexes inhibit (via FcgRIIB) rather than activate (via FcgRIIIA) basophils. They also show an inhibitory effect of IgG on IgE-mediated basophil activation, suggesting that the lack of an inhibitory signal by IgG1 could contribute to the increased IgE-mediated anaphylaxis we observed in IgEki/ki mice [18, 21]. First, we used CD23−/− to avoid passive binding of IgE to B cells.

It is suggested that IFN-γ +874 AA genotype and A allele are risk factors for developing brucellosis infection in Iranian subjects. “
“Citation Morales-Prieto

DM, Schleussner E, Markert UR. Reduction in miR-141 is Induced by Leukemia Inhibitory Factor and Inhibits Proliferation in Choriocarcinoma Cell line JEG-3. Am J Reprod Immunol 2011; 66 (Suppl. 1): 57–62 Starting from the peri-implantation period, leukemia inhibitory factor (LIF) is a major regulator of trophoblast functions. Micro-RNAs (miRNA) are short non-coding RNA sequences, which regulate expression of genes at post-transcriptional level. The influence of LIF on miRNA expression in trophoblastic cells has not yet been analyzed and was focus of this investigation. JEG-3 choriocarcinoma cells have been stimulated with LIF for 1, 2, 4, 6, and 24 hr. The expression of miR-9, miR-141, miR-21, miR-93, selleck chemical and let-7g has been analyzed by real-time PCR. Subsequently, miR-141 has been silenced and over-expressed to test its role in the proliferation of JEG-3 cells after 24 and 48 hr. MiR-141 has been significantly downregulated by more than 50% after LIF stimulation, while miR-21 and miR-93 expression has been significantly upregulated. Silencing of miR-141 completely inhibited the proliferation

EGFR inhibitor of JEG-3 cells, while over-expression had no effect. LIF regulates expression of miRNA in trophoblastic Urease cells, which may be responsible for several functional effects induced by LIF. Leukemia inhibitory factor (LIF) induces tyrosine phosphorylation of signal transducer and activator of transcription 3 (STAT3) in several trophoblast

and choriocarcinoma cell types and lines (summarized in1). This event triggers several trophoblastic functions, such as migration, invasion or induction and suppression of expression of a variety of genes.2,3 Because functional effects have been observed after several days, it cannot be excluded that parts thereof are secondary or indirectly induced. We argue that micro-RNA (miRNA) may be involved in the regulation of these previously observed LIF-induced functions. For this reason, we have selected a panel of five miRNAs which have been described to influence STAT3 expression or which are known to be expressed on full activation of STAT3. MiRNAs constitute a novel group of regulatory molecules that play a pivotal role in the control of gene expression at post-transcriptional level. The number of miRNAs described thus far arises approximately 1000 (MiRBase V16), which may regulate up to 30% of the human genome.4 The signature of miRNA expression is regulated in a tissue- and developmental stage-specific manner, and thereby, it may be used as a biomarker for the identification of certain physiological or pathological events including malignancies.

These downstream targets can be divided into pro-inflammatory chemokines (CXCL1, CXCL8, CXCL10), cytokines [tumour necrosis factor-α (TNF-α), IL-1, IL-6, and granulocyte–macrophage and granulocyte colony-stimulating factors], anti-microbial peptides (mucins, β-defensins, S100A7-9), and tissue remodelling and acute-phase

responses (SAA, MMP1, RANKL).26 Furthermore, the combined action BMN 673 clinical trial of IL-17A or IL-17F with other cytokines such as TNF-α, IL-1β and interferon-γ synergistically augments the induction of pro-inflammatory responses from various target cells.27–29 As both IL-17A and IL-17F regulate neutrophil mobilization by promoting granulopoiesis, inflammation is observed when either cytokine is over-expressed in vivo.26,30–33 In vivo studies substantiate the importance of these cytokines in anti-microbial responses. Host defence pathways are impaired in mice that are deficient in either or both cytokines. Infection of il17a−/−, il17f−/− and il17a−/−:il17f−/− mice with either Citrobacter rodentium or Staphylococcus aureus resulted

in increased bacterial burden and pathology, signifying the requirement of these cytokines in defence against Gram-negative and Gram-positive bacteria.34,35 Clearance of the pulmonary pathogen HIF inhibitor review Klebsiella pneumoniae was also defective in il17a−/− mice.35 Theses phenotypes are attributed to defective granulocyte colony-stimulating factor responses, granulopoiesis, and neutrophil mobilization.35,36 Additional infection models reveal the importance of this pathway in anti-fungal immunity. Neutralizing IL-17A with a blocking antibody increases fungal burden in a model of Pneumocystis carinii infection, while over-expressing IL-17A using an adenoviral system protects mice infected with lethal doses of Candida albicans.37,38 Interleukin-17A cAMP also plays a role in immunity to intracellular bacteria. However, il17a−/− mice are not susceptible to primary infections with

intracellular bacterial pathogens such as Mycobacterium tuberculosis and Listeria monocytogenes, which require Th1 immunity for eradication. Instead, IL-17A is critical for the enhancement of memory responses against these pathogens.35 Collectively, these studies demonstrate the importance of these cytokines in host defence against bacteria and fungi. Although these proteins play a protective role in host defence, excessive activation of this pathway contributes to autoimmunity.13 Both IL-17A and IL-17F are elevated in multiple human autoimmune diseases (Table 3).9,34,39–46 Pre-clinical models of rheumatoid arthritis (RA), multiple sclerosis (MS) and inflammatory bowel disease (IBD) suggest that these proteins participate in disease pathogenesis, but the contribution of each cytokine to the development of disease varies, with IL-17A playing a more dominant role in RA and MS, whereas IL-17F is more important in IBD.