Cytokines induce effector T-helper cells during invasive aspergillosis; what we have learned about T-helper cells?

Serum Cytokine Changes in a Patient with Chronic Pulmonary Aspergillosis Overlapping with Allergic Bronchopulmonary Aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA) and chronic pulmonary aspergillosis (CPA) are diseases caused by Aspergillus infection, and CPA can develop from ABPA in some cases. We herein report a patient with CPA overlapping with ABPA. Serum cytokine levels were evaluated at 4 time points: the ABPA diagnosis, CPA diagnosis, 6 months after the start of voriconazole (VRCZ), and 12 months after re-administration of VRCZ. Interleukin (IL)-13 levels decreased upon glucocorticoid treatment, whereas IL-25 and IL-33 levels decreased rapidly with the initiation of antifungals. Early antifungal therapy may be important to control disease progression and prevent CPA overlap.

Interplay of Cytokines and Chemokines in Aspergillosis

Aspergillosis is a fungal infection caused by various species of Aspergillus, most notably A. fumigatus. This fungus causes a spectrum of diseases, including allergic bronchopulmonary aspergillosis, aspergilloma, chronic pulmonary aspergillosis, and invasive aspergillosis. The clinical manifestations and severity of aspergillosis can vary depending on individual immune status and the specific species of Aspergillus involved. The recognition of Aspergillus involves pathogen-associated molecular patterns (PAMPs) such as glucan, galactomannan, mannose, and conidial surface proteins. These are recognized by the pathogen recognition receptors present on immune cells such as Toll-like receptors (TLR-1,2,3,4, etc.) and C-type lectins (Dectin-1 and Dectin-2). We discuss the roles of cytokines and pathogen recognition in aspergillosis from both the perspective of human and experimental infection. Several cytokines and chemokines have been implicated in the immune response to Aspergillus infection, including interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), CCR4, CCR17, and other interleukins. For example, allergic bronchopulmonary aspergillosis (ABPA) is characterized by Th2 and Th9 cell-type immunity and involves interleukin (IL)-4, IL-5, IL-13, and IL-10. In contrast, it has been observed that invasive aspergillosis involves Th1 and Th17 cell-type immunity via IFN-γ, IL-1, IL-6, and IL-17. These cytokines activate various immune cells and stimulate the production of other immune molecules, such as antimicrobial peptides and reactive oxygen species, which aid in the clearance of the fungal pathogen. Moreover, they help to initiate and coordinate the immune response, recruit immune cells to the site of infection, and promote clearance of the fungus. Insight into the host response from both human and animal studies may aid in understanding the immune response in aspergillosis, possibly leading to harnessing the power of cytokines or cytokine (receptor) antagonists and transforming them into precise immunotherapeutic strategies. This could advance personalized medicine.

Circulatory Inflammatory Proteins as Early Diagnostic Biomarkers for Invasive Aspergillosis in Patients with Hematologic Malignancies-an Exploratory Study

OBJECTIVES

Invasive aspergillosis (IA) is a major cause of mortality in immunocompromised patients and it is difficult to diagnose because of the lack of reliable highly sensitive diagnostics. We aimed to identify circulating immunological markers that could be useful for an early diagnosis of IA.

METHODS

We collected longitudinally serum samples from 33 cases with probable/proven IA and two matched control cohorts without IA (one with microbiological and clinical evidence of bacterial or viral non-fungal pneumonia and one without evidence of infection, all matched for neutropenia, primary underlying disease, and receipt of corticosteroids/other immunosuppressants) at a tertiary university hospital. In addition, samples from an independent cohort (n = 20 cases of proven/probable IA and 20 matched controls without infection) were obtained. A panel of 92 circulating proteins involved in inflammation was measured by proximity extension assay. A random forest model was used to predict the development of IA using biomarkers measured before diagnosis.

RESULTS

While no significant differences were observed between IA cases and infected controls, concentrations of 30 inflammatory biomarkers were different between cases and non-infected controls, of which nine were independently replicated: PD-L1, MMP-10, Interleukin(IL)-10, IL-15RA, IL-18, IL-18R1, CDCP1, CCL19 and IL-17C. From the differential abundance analysis of serum samples collected more than 10 days before diagnosis and at diagnosis, increased IL-17C concentrations in IA patients were replicated in the independent cohort.

CONCLUSIONS

An increased circulating concentration of IL-17C was detected both in the discovery and independent cohort, both at the time of diagnosis and in samples 10 days before the diagnosis of IA, suggesting it should be evaluated further as potential (early) biomarker of infection.

Abnormal adenosine metabolism of neutrophils inhibits airway inflammation and remodeling in asthma model induced by Aspergillus fumigatus

BACKGROUND

Neutrophils consume a large amount of energy when performing their functions. Compared with other white blood cells, neutrophils contain few mitochondria and mainly rely on glycolysis and gluconeogenesis to produce ATP. The inflammatory site is hypoxic and nutrient poor. Our aim is to study the role of abnormal adenosine metabolism of neutrophils in the asthmatic airway inflammation microenvironment.

METHOD

In this study, an asthma model was established by intratracheal instillation of Aspergillus fumigatus extract in Ecto-5'-Nucleotidase (CD73) gene-knockout and wild-type mice. Multiple analyses from bronchoalveolar lavage fluid (BALF) were used to determine the levels of cytokines and chemokines. Immunohistochemistry was used to detect subcutaneous fibrosis and inflammatory cell infiltration. Finally, adenosine 5'-(α, β-methylene) diphosphate (APCP), a CD73 inhibitor, was pumped subcutaneously before Aspergillus attack to observe the infiltration of inflammatory cells and subcutaneous fibrosis to clarify its therapeutic effect.

RESULT

PAS staining showed that CD73 knockout inhibited pulmonary epithelial cell proliferation and bronchial fibrosis induced by Aspergillus extract. The genetic knockdownof CD73 significantly reduced the production of Th2 cytokines, interleukin (IL)-4, IL-6, IL-13, chemokine (C-C motif) ligand 5 (CCL5), eosinophil chemokine, neutrophil IL-17, and granulocyte colony-stimulating factor (G-CSF). In addition, exogenous adenosine supplementation increased airway inflammation. Finally, the CD73 inhibitor APCP was administered to reduce inflammation and subcutaneous fibrosis.

CONCLUSION

Elevated adenosine metabolism plays an inflammatory role in asthma, and CD73 could be a potential therapeutic target for asthma.

Invasive aspergillosis in liver transplant recipients

BACKGROUND

Liver transplantation is increasing worldwide with underlying pathologies dominated by metabolic and alcoholic diseases in developed countries.

METHODS

We provide a narrative review of invasive aspergillosis (IA) in liver transplant (LT) recipients. We searched PubMed and Google Scholar for references without language and time restrictions.

RESULTS

The incidence of IA in LT recipients is low (1.8%), while mortality is high (∼50%). It occurs mainly early (<3 months) after LT. Some risk factors have been identified before (corticosteroid, renal, and liver failure), during (massive transfusion and duration of surgical procedure), and after transplantation (intensive care unit stay, re-transplantation, re-operation). Diagnosis can be difficult and therefore requires full radiological and clinicobiological collaboration. Accurate identification of Aspergillus species is recommended due to the cryptic species, and susceptibility testing is crucial given the increasing resistance of Aspergillus fumigatus to azoles. It is recommended to reduce the dose of tacrolimus (50%) and to closely monitor the trough level when introducing voriconazole, isavuconazole, and posaconazole. Surgery should be discussed on a case-by-case basis. Antifungal prophylaxis is recommended in high-risk patients. Environmental preventative measures should be implemented to prevent outbreaks of nosocomial aspergillosis in LT recipient units.

CONCLUSION

IA remains a very serious disease in LT patients and should be promptly sought and, if possible, prevented by clinicians when risk factors are identified.

Neuroimmune Responses in a New Experimental Animal Model of Cerebral Aspergillosis

Exposure of immunosuppressed individuals to the opportunistic fungal pathogen Aspergillus fumigatus may result in invasive pulmonary aspergillosis (IPA), which can lead to the development of cerebral aspergillosis (CA), a highly lethal infection localized in the central nervous system (CNS). There are no experimental models of CA that effectively mimic human disease, resulting in a considerable knowledge gap regarding mechanisms of neurological pathogenicity and neuroimmune responses during infection. In this report, immunosuppressed mice (via acute, high-dose corticosteroid administration) challenged with A. fumigatus resting conidia intranasally, followed a day later by a 70-fold lower inoculum of pre-swollen conidia intravenously (IN + IV + steroid), demonstrated increased weight loss, signs of severe clinical disease, increased fungal burden in the brain, and significant reduction in survival compared to immunosuppressed mice challenged intranasally only (IN + steroid) or non-immunosuppressed mice challenged both intranasally and intravenously (IN + IV). The IN + IV + steroid group demonstrated significant decreases in monocytes, eosinophils, dendritic cells (DCs), and invasive natural killer T (iNKT) cells, but not neutrophils or γδ T cells, in the brain compared to the IN + IV group. Likewise, the IN + IV + steroid group had significantly lower levels of interleukin (IL)-1β, IL-6, IL-17A, CC motif chemokine ligand 3 (CCL3), CXC chemokine ligand 10 (CXCL10), and vascular endothelial growth factor (VEGF) in the brain compared to the IN + IV group. IN + IV + steroid was superior to both IN + IV + chemotherapy (cytarabine + daunorubicin) and IN + IV + neutropenia for the development of CA. In conclusion, we have developed a well-defined, physiologically relevant model of disseminated CA in corticosteroid-induced immunosuppressed mice with a primary pulmonary infection. This model will serve to advance understanding of disease mechanisms, identify immunopathogenic processes, and help define the protective neuroinflammatory response to CA. IMPORTANCE Invasive fungal infections (IFIs) result in significant mortality in immunosuppressed individuals. Of these, invasive pulmonary aspergillosis (IPA), caused by the opportunistic mold Aspergillus fumigatus, is the most lethal. Lethality in IPA is due to two main factors: destruction of the lung leading to compromised pulmonary function, and dissemination of the organism to extrapulmonary organs. Of these, the CNS is the most common site of dissemination. However, very little is known regarding the pathogenesis of or immune response during cerebral aspergillosis, which is directly due to the lack of an animal model that incorporates immunosuppression, lung infection, and consistent dissemination to the CNS/brain. In this report, we have developed a new experimental animal model of CA which includes the above parameters and characterized the neuroimmune response. We further compared this disseminated CA model to two additional immunosuppressive strategies. Overall, this model of disseminated CA following IPA in an immunosuppressed host provides a novel platform for studying the efficacy of antifungal drugs and immunotherapies for improving disease outcomes.

T-cell epitope-based vaccine prediction against Aspergillus fumigatus: a harmful causative agent of aspergillosis

Background

Among the most common causes of invasive aspergillosis and acute bronchopulmonary aspergillosis is Aspergillus fumigatus. Transmission with A. fumigatus produces aggressive aspergillosis in allogeneic haematopoietic stem cell transplant recipients, HIV patients, and cancer patients. Asthmatics and cystic fibrosis patients are allergic to A. fumigatus. MHC class-II binding epitopes can initiate immunogenic responses in patients. In this study, we deployed immunoinformatic study to reveal epitopes from fungal proteins.

Results

In modern research, we found multiple epitopes ITLKLLHRYSYKLAG, KLVLRAFPNHFRGDS, RYSYKLAGVNQVDVV, GKSFELNQAARAVTQ, and LHRYSYKLAGVNQVD from crucial proteins of A. fumigatus 5,8-linoleate diol synthase (ACO55067.2) and ChainB-chitinase A1 (2XVN_B). RYSYKLAGVNQVDVV, GKSFELNQAARAVTQ, and LHRYSYKLAGVNQVD epitopes interact with HLA-DRB01_0101, while ITLKLLHRYSYKLAG and KLVLRAFPNHFRGDS epitopes interact with HLA-DRB01_1501. Molecular docking analysis reveals atomic contact energy (ACE) value for these five epitopes shown below −5 Kcal/mol in docked state.

Conclusions

The invasive aspergillosis and acute bronchopulmonary aspergillosis are caused by harmful fungal pathogen Aspergillus fumigatus. Our modern immunoinformatic research shows ITLKLLHRYSYKLAG, KLVLRAFPNHFRGDS, RYSYKLAGVNQVDVV, GKSFELNQAARAVTQ, and LHRYSYKLAGVNQVD epitopes could bind to MHC-II HLA allelic determinants and can initiate immunogenic response in patients affected by Aspergillus fumigatus.

Food Habit Associated Mycobiota Composition and Their Impact on Human Health

Mycobiota is not only associated with healthy homeostasis in the human gut but also helps to adapt to the environment. Food habits, alcohol consumption, intake of probiotics, and contaminated food with a mycotoxin, often lead to the alteration in the mycobiota composition. Impaired immunity of the host may affect fungal symbiosis leading to mycosis. The human gut adapts to the commensalism fungi belonging to the phylum Ascomycota and Basidiomycota. Diet habits such as plant-or animal-based, phytoestrogens enriched plant products, fat-rich diets also influence the colonization of certain fungal species in the mammalian gut. Food habits or mycotoxin-contaminated food or fungal peptides have an impact on bacterial-fungal interaction and human health. The mycobiota population such as Fusarium, Humicola, Aspergillus, and Candida are altered due to alcohol intake in alcoholic liver disease. The role of associated gut mycobiota due to irregular bowel habits or lifestyle change has been observed in inflammatory bowel disease. In this review, it has been observed that Saccharomyces, Aspergillus, Fusarium, Cladosporium, Candida, and Malassezia were the common genus in the human mycobiota. Therefore, this study focused on how diet habits and alcohol intake, among others., influence mycobiota composition that may affect the human immune system or overall health.

Pediatric allergic fungal rhinosinusitis: optimizing outcomes

PURPOSE OF REVIEW

Allergic fungal rhinosinusitis (AFRS) is a debilitating condition for children. Despite there being several reviews on this topic in the adult population, there is a paucity of reviews of AFRS in the pediatric literature. This article reviews the recent evidence of pediatric AFRS with the aim to optimize outcomes of pediatric patients with this condition.

RECENT FINDINGS

AFRS is clinically characterized by nasal polyposis, a type I hypersensitivity to fungal epitopes, very thick eosinophilic mucin, and peripheral eosinophilia. Pediatric AFRS has similar clinical characteristics to that in adults but is thought to have a more aggressive nature, with higher serum immunoglobulin E and more frequently bone erosion and malformation of facial bones. Diagnosis of pediatric AFRS is made by using the Bent and Kuhn's criteria developed for adult AFRS. The mainstay of treatment is surgery followed by postoperative corticosteroids. Adjunctive therapies, including topical/oral antifungal agents, allergen immunotherapy and biologics may improve outcomes in pediatric AFRS, but to date the current evidence is limited.

SUMMARY

To optimize the outcome of pediatric AFRS, adequate and early diagnosis and treatment are essential. Appropriate and comprehensive endoscopic sinus surgery to open the sinuses, remove the fungal burden of disease and improve access of the sinuses to postoperative topical corticosteroid remains the standard of care.

Allergic bronchopulmonary aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA) is an inflammatory disease caused by immunologic reactions initiated against Aspergillus fumigatus colonizing the airways of patients with asthma and cystic fibrosis. The common manifestations include treatment-resistant asthma, transient and fleeting pulmonary opacities and bronchiectasis. It is believed that globally there are about five million cases of ABPA, with India alone accounting for about 1.4 million cases. The occurrence of ABPA among asthmatic patients in special clinics may be as high as 13 per cent. Thus, a high degree of suspicion for ABPA should be entertained while treating a patient with bronchial asthma, particularly in specialized clinics. Early diagnosis and appropriate treatment can delay (or even prevent) the onset of bronchiectasis, which suggests that all patients of bronchial asthma should be screened for ABPA, especially in chest clinics. The current review summarizes the recent advances in the pathogenesis, diagnosis and management of ABPA.

Glucose - The X factor for the survival of human fungal pathogens and disease progression in the host

The incidence of human fungal infections is increasing due to the expansion of the immunocompromised patient population. The continuous use of different antifungal agents has eventually resulted in the establishment of resistant fungal species. The fungal pathogens unfold multiple resistance strategies to successfully tackle the effect of different antifungal agents. For the successful colonization and establishment of infection inside the host, the pathogenic fungi switch to the process of metabolic flexibility to regulate distinct nutrient uptake systems as well as to modulate their metabolism accordingly. Glucose the most favourable carbon source helps carry out the important survival and niche colonization processes. Adopting glucose as the center, this review has been put forward to provide an outline of the important processes like growth, the progression of infection, and the metabolism regulated by glucose, affecting the pathogenicity and virulence traits in the human pathogenic fungi. This could help in the identification of better treatment options and appropriate target-oriented antifungal drugs based on the glucose-regulated pathways and processes. In the article, we have also presented a summary of the novel studies and findings pointing to glucose-based potential therapeutic avenues to be explored to tackle the problem of globally increasing multidrug-resistant human fungal infections.

Advances in Fungal Peptide Vaccines

Vaccination is one of the greatest public health achievements in the past century, protecting and improving the quality of life of the population worldwide. However, a safe and effective vaccine for therapeutic or prophylactic treatment of fungal infections is not yet available. The lack of a vaccine for fungi is a problem of increasing importance as the incidence of diverse species, including Paracoccidioides, Aspergillus, Candida, Sporothrix, and Coccidioides, has increased in recent decades and new drug-resistant pathogenic fungi are emerging. In fact, our antifungal armamentarium too frequently fails to effectively control or cure mycoses, leading to high rates of mortality and morbidity. With this in mind, many groups are working towards identifying effective and safe vaccines for fungal pathogens, with a particular focus of generating vaccines that will work in individuals with compromised immunity who bear the major burden of infections from these microbes. In this review, we detail advances in the development of vaccines for pathogenic fungi, and highlight new methodologies using immunoproteomic techniques and bioinformatic tools that have led to new vaccine formulations, like peptide-based vaccines.

The Skin as a Window into Primary Immune Deficiency Diseases: Atopic Dermatitis and Chronic Mucocutaneous Candidiasis

Primary immune deficiency diseases characteristically present with recurrent, severe, or unusual infections. These infections may often involve the skin, with mucocutaneous candidal infections seen in a variety of different primary immune deficiencies. Primary immune deficiencies may also present with noninfectious cutaneous complications, of which eczema is the most common. In a patient with suspected primary immune deficiency, the presence of eczema or candidal skin infections offers critical information about the underlying immune defect, either the presence of atopy or defect in the T_H17 pathway, respectively. These skin manifestations also are often early or heralding findings of the underlying immunologic disease. Therefore, awareness of associations between these skin findings and specific immune deficiencies may aide in the early detection and treatment of serious or life-threatening immunologic defects. This review specifically will focus on the primary immune deficiencies commonly associated with eczema or mucocutaneous candidiasis.

Impact of immunosuppressive and antifungal drugs on PBMC- and whole blood-based flow cytometric CD154+ Aspergillus fumigatus specific T-cell quantification

Flow cytometric quantification of CD154⁺ mould specific T-cells in antigen-stimulated peripheral blood mononuclear cells (PBMCs) or whole blood has been described as a supportive biomarker to diagnose invasive mould infections and to monitor therapeutic outcomes. As patients at risk frequently receive immunosuppressive and antifungal medication, this study compared the matrix-dependent impact of representative drugs on CD154⁺ T-cell detection rates. PBMCs and whole blood samples from healthy adults were pre-treated with therapeutic concentrations of liposomal amphotericin B, voriconazole, posaconazole, cyclosporine A (CsA) or prednisolone. Samples were then stimulated with an Aspergillus fumigatus lysate or a viral antigen cocktail (CPI) and assessed for CD154⁺ T-helper cell frequencies. Specific T-cell detection rates and technical assay properties remained largely unaffected by exposure of both matrices to the studied antifungals. By contrast, CsA and prednisolone pre-treatment of isolated PBMCs and whole blood adversely impacted specific T-cell detection rates and caused elevated inter-replicate variation. Unexpectedly, the whole blood-based protocol that uses additional α-CD49d co-stimulation was less susceptible to CsA and prednisolone despite prolonged drug exposure in the test tube. Accordingly, addition of α-CD49d during PBMC stimulation partially attenuated the impact of immunosuppressive drugs on test performance. Translating these results into the clinical setting, false-negative results of CD154⁺ antigen-specific T-cell quantification need to be considered in patients receiving T-cell-active immunosuppressive medication. Optimized co-stimulation regimes with α-CD49d could contribute to an improved feasibility of functional T-cell assays in immunocompromised patient populations.

Anti-melanogenic activity of Myristica fragrans extract against Aspergillus fumigatus using phenotypic based screening

Background

Aspergillus fumigatus, an opportunistic fungal pathogen is associated with a wide array of diseases. It produces 1, 8-dihydroxy naphthalene (DHN) melanin that imparts greenish grey color to conidia and is an important virulence factor. It masks various molecular patterns associated with A. fumigatus and protects the fungus from host immune system. Myristica fragrans, enriched with secondary metabolites has been traditionally used for the treatment of infectious and inflammatory diseases. The present study was aimed to explore the anti-melanogenic effect of M. fragrans extracts on A. fumigatus.

Methods

M. fragrans extracts (hexane, chloroform, methanol and ethanol) were prepared through polarity guided extraction. Phytochemical analysis was performed to detect the chemical constituents of the extracts. The minimum effective concentration (MEC) of the extracts against A. fumigatus melanin was determined by broth micro-dilution assay. Various virulence factors were assayed by spectrophotometric methods. Electron microscopic studies were performed to evaluate the effect of the hexane extract of M. fragrans on A. fumigatus cell surface morphology. The major active compounds of the extract were detected by gas chromatography-mass spectrometry (GC-MS). Docking was performed to study the interaction between the major identified compounds and the ketosynthase domain of polyketide synthase protein.

Results

The results indicated that the hexane extract of M. fragrans inhibited melanin production (76.09%), reduced ergosterol content (83.63%) and hydrophobicity of the cell (72.2%) at the MEC of 0.078 mg/mL. Altered conidial surface, disappearance of protrusions and absence of melanin layer on outer cell surface was observed in electron microscopy. Forty-two compounds were identified by GC-MS. The main constituents were identified as sabinene (12.2%), linoleic acid (11.7%), hexadecanoic acid (10.5%), safrole (8.1%) and elemicin (7.8%). Docking studies revealed that hexadecanoic acid, its derivative compound cis-9-hexadecenal and isoeugenol have lower binding energy forming proper hydrogen bond with ketosynthase domain of polyketide synthase protein.

Conclusion

The study concludes that the extract of M. fragrans has potential antifungal properties that can be explored in combination with available antifungals. This combination approach may be helpful for large number of patients suffering with A. fumigatus infections.

Immune Parameters for Diagnosis and Treatment Monitoring in Invasive Mold Infection

Infections caused by invasive molds, including Aspergillus spp., can be difficult to diagnose and remain associated with high morbidity and mortality. Thus, early diagnosis and targeted systemic antifungal treatment remains the most important predictive factor for a successful outcome in immunocompromised individuals with invasive mold infections. Diagnosis remains difficult due to low sensitivities of diagnostic tests including culture and other mycological tests for mold pathogens, particularly in patients on mold-active antifungal prophylaxis. As a result, antifungal treatment is rarely targeted and reliable markers for treatment monitoring and outcome prediction are missing. Thus, there is a need for improved markers to diagnose invasive mold infections, monitor response to treatment, and assist in determining when antifungal therapy should be escalated, switched, or can be stopped. This review focuses on the role of immunologic markers and specifically cytokines in diagnosis and treatment monitoring of invasive mold infections.

Increased Efficacy of Oral Fixed-Dose Combination of Amphotericin B and AHCC® Natural Adjuvant against Aspergillosis

Invasive pulmonary aspergillosis represents one of the most serious fungal infections among immunocompromised patients. In this study, we aimed to analyze the in vivo efficacy of prophylactic oral amphotericin B (AMB) encapsulated in modified chitosan-nanoparticles (Nanomerics’ Molecular Envelope Technology (MET)) supplemented with a standardized extract of cultured Lentinula edodes mycelia (AHCC^®) in a murine model of pulmonary aspergillosis. We determined fungal burden and survival of mice and additionally, we carried out a cytokine analysis in an attempt to understand the immunomodulation of the extract. Our results evidenced equivalent efficacy between orally administered AMB-MET and the intravenous liposomal AMB marketed formulation. Addition of the AHCC^® supplement significantly improved efficacy in terms of burden reduction and survival increase of both oral and intravenous AMB therapies compared to the untreated control group. Moreover, a protective effect of the extract was observed in terms of weight loss. Regarding the cytokine profiles, the Th1 immune response was stimulated in treated animals when compared to the control group. This response was marked by an enhancement in the MCP-1, GM-CSF, VEGF, RANTES and IL-17 levels and a decrease in the IL-6, a biomarker related to the severity of the infection.

Docking analysis of hexanoic acid and quercetin with seven domains of polyketide synthase A provided insight into quercetin-mediated aflatoxin biosynthesis inhibition in Aspergillus flavus

Studies on phytochemicals as anti-aflatoxigenic agents have gained importance including quercetin. Thus, to understand the molecular mechanism behind inhibition of aflatoxin biosynthesis by quercetin, interaction study with polyketide synthase A (PksA) of Aspergillus flavus was undertaken. The 3D structure of seven domains of PksA was modeled using SWISS-MODEL server and docking studies were performed by Autodock tools-1.5.6. Docking energies of both the ligands (quercetin and hexanoic acid) were compared with each of the domains of PksA enzyme. Binding energy for quercetin was lesser that ranged from - 7.1 to - 5.25 kcal/mol in comparison to hexanoic acid (- 4.74 to - 3.54 kcal/mol). LigPlot analysis showed the formation of 12 H bonds in case of quercetin and 8 H bonds in hexanoic acid. During an interaction with acyltransferase domain, both ligands showed H bond formation at Arg63 position. Also, in product template domain, quercetin creates four H bonds in comparison to one in hexanoic acid. Our quantitative RT-PCR analysis of genes from aflatoxin biosynthesis showed downregulation of pksA, aflD, aflR, aflP and aflS at 24 h time point in comparison to 7 h in quercetin-treated A. flavus. Overall results revealed that quercetin exhibited the highest level of binding potential (more number of H bonds) with PksA domain in comparison to hexanoic acid; thus, quercetin possibly inhibits via competitively binding to the domains of polyketide synthase, a key enzyme of aflatoxin biosynthetic pathway. Further, we propose that key enzymes from aflatoxin biosynthetic pathway in aflatoxin-producing Aspergilli could be explored further using other phytochemicals as inhibitors.

Proteome Analysis Revealed Jak/Stat Signaling and Cytoskeleton Rearrangement Proteins in Human Lung Epithelial Cells During Interaction with Aspergillus terreus

Background:

Aspergillus terreus is an emerging etiological agent of invasive and allergic aspergillosis in immunocompromised individuals. The main risk groups are individuals having cancer, acute leukemia and those who undergo bone marrow transplantation. The human lung epithelial cells constitute the first line of defense against inhaled conidia of A. terreus. The aim of the study was to understand how human lung epithelial cells respond to A. terreus conidia during the interaction and to decipher proteins/pathways underlying in host defense.

Methods:

Protein samples were extracted from human lung epithelial cells (A549) infected with and without A. terreus conidia. Proteins were identified using QTOF-LC-MS/MS followed by analysis using Protein Lynx Global Services software (2.2.5) against Homo sapiens UniProt database.

Results:

A total of 1253 proteins in human lung epithelial cells were identified during the interaction with Aspergillus terreus conidia, whereas 427 proteins were identified in uninfected lung epithelial cells. We have observed 63 proteins in both the conditions. Gene ontology and KEEG pathway analysis of proteins from infected lung epithelial cells showed proteins from cytoskeleton rearrangement, transport, transcription and signal transduction pathways, such as Jak/Stat, NOD like receptor signaling, Toll–like receptor signaling, NF-kβ signaling and TNF signaling pathways. These signaling proteins suggested the strong immune response in lung epithelial cells against A. terreus conidia. Also, cytoskeleton rearrangement proteins depicted the internalization of A. terreus conidia by human lung epithelial cells.

Conclusion:

Our study has contributed to understand the interaction response of human lung epithelial cells during A. terreus infection. Also, our study may facilitate the identification of inflammatory biomarker against A. terreus.

Resistance mechanism and proteins in Aspergillus species against antifungal agents

Aspergillus

species contain pathogenic and opportunistic fungal pathogens which have the potential to cause mycosis (invasive aspergillosis) in humans. The existing antifungal drugs have limitation largely due to the development of drug-resistant isolates. To gain insight into the mechanism of action and antifungal drug resistance in Aspergillus species including biofilm formation, we have reviewed protein data of Aspergillus species during interaction with antifungals drugs (polynes, azoles and echinocandin) and phytochemicals (artemisinin, coumarin and quercetin). Our analyses provided a list of Aspergillus proteins (72 proteins) that were abundant during interaction with different antifungal agents. On the other hand, there are 26 proteins, expression level of which is affected by more than two antifungal agents, suggesting the more general response to the stress induced by the antifungal agents. Our analysis showed enzymes from cell wall remodelling, oxidative stress response and energy metabolism are the responsible factors for providing resistance against antifungal drugs in Aspergillus species and could be explored further in clinical isolates. Also, these findings have clinical importance since the effect of drug targeting different proteins can be potentiated by combination therapy. We have also discussed the opportunities ahead to study the functional role of proteins from environmental and clinical isolates of Aspergillus during its interaction with the antifungal drugs.

Abbreviations

IPA: invasive pulmonary aspergillosis; IA: invasive aspergillosis; AmB: Amphotericin B; CAS: Caspofungin; VRC: Voriconazole; ITC: Itraconazole; POS: Posaconazole; ART: Artemisinin; QRT: Quercetin; CMR: Coumarin; MIC: minimal inhibitory concentration

Eosinophil-Associated Innate IL-17 Response Promotes Aspergillus fumigatus Lung Pathology

Aspergillus fumigatus is a common widespread microorganism with environmental, biological and clinical relevance. After inhalation, swollen conidia can germinate, colonize and invade pulmonary tissues. Eosinophils have been described as key cells in A. fumigatus lung infection. However, their specific role in protecting or damaging lung tissue as well as their relatioship among different A. fumigatus strains is poorly understood. Previously, it has been reported that eosinophils are able to produce IL-17 and mediate an innate response that protected mice from infection using Af293 and CEA10 strains. Here, we have developed a set of new experiments with the CEA17-derived A1163 strain of A. fumigatus. Using ΔdblGATA1 mice, we demonstrate that eosinophils produce IL-17 and are involved in control of neutrophil, macrophage and lymphocyte recruitment. We found that eosinophils also induce high levels of cytokines and chemokines, generating an intense inflammatory process. Eosinophils are responsible for increased pulmonary dysfunction and elevated lethality rates in mice. Curiously, fungal burden was not affected. To address the role of IL-17 signaling, pharmacological inhibition of this mediator in the airways with anti-IL-17 antibody was able to reduce inflammation in the airways and protect infected mice. In conclusion, our results demonstrate that eosinophils control IL-17-mediated response and contribute to lung pathology after A. fumigatus infection. Therefore, eosinophils may represent a potential target for controlling exacerbated inflammation and prevent tissue damage during this fungal infection.

Immunomodulation as a Therapy for Aspergillus Infection: Current Status and Future Perspectives

Invasive aspergillosis (IA) is the most serious life-threatening infectious complication of intensive remission induction chemotherapy and allogeneic stem cell transplantation in patients with a variety of hematological malignancies. Aspergillus fumigatus is the most commonly isolated species from cases of IA. Despite the various improvements that have been made with preventative strategies and the development of antifungal drugs, there is an urgent need for new therapeutic approaches that focus on strategies to boost the host’s immune response, since immunological recovery is recognized as being the major determinant of the outcome of IA. Here, we aim to summarize current knowledge about a broad variety of immunotherapeutic approaches against IA, including therapies based on the transfer of distinct immune cell populations, and the administration of cytokines and antibodies.

β-1,3-glucan-lacking Aspergillus fumigatus mediates an efficient antifungal immune response by activating complement and dendritic cells

Complement system and dendritic cells (DCs) form - beside neutrophils and macrophages - the first line of defense to combat fungal infections. Therefore, we here studied interactions of these first immune elements with Aspergillus fumigatus lacking ß-1,3-glucans (fks1_tetOn^rep under repressed conditions) to mechanistically explain the mode of action of echinocandins in more detail. Echinocandins are cell wall active agents blocking β-glucan synthase, making the A. fumigatus fks1_tetOn mutant a good model to study immune-modulatory actions of these drugs. We now demonstrate herein, that complement was activated to significantly higher levels by the fks1-deficient strain compared to its respective wild type. This enhanced covalent linking of complement fragments to the A. fumigatus fks1_tetOn^rep mutant further resulted in enhanced DC binding and internalization of the fungus. Additionally, we found that fks1_tetOn^rep induced a Th1-/Th17-polarizing cytokine profile program in DCs. The effect was essentially dependent on massive galactomannan shedding, since blocking of DC-SIGN significantly reduced the fks1_tetOn^rep-mediated induction of an inflammatory cytokine profile.Our data demonstrate that lack of ß-1,3-glucan, also found under echinocandin therapy, results in improved recognition of Aspergillus fumigatus by complement and DCs and therefore not only directly affects the fungus by its fungistatic actions, but also is likely to exert indirect antifungal mechanisms by strengthening innate host immune mechanisms.Abbreviations: C: complement; CR:complement receptor; DC: dendritic cell; iDC: immature dendritic cell; DC-SIGN: Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin; ERK: extracellular signal-regulated kinases; JNK : c-Jun N-terminal kinases; MAPK: mitogen-activated protein kinase; NHS: normal human serum; PRR: pattern recognition receptor; Th :T helper; TLR :Toll-like receptor; WT: wild type.

RNA-Seq Profile Reveals Th-1 and Th-17-Type of Immune Responses in Mice Infected Systemically with Aspergillus fumigatus

With the increasing numbers of immunocompromised hosts, Aspergillus fumigatus emerges as a lethal opportunistic fungal pathogen. Understanding innate and acquired immunity responses of the host is important for a better therapeutic strategy to deal with aspergillosis patients. To determine the transcriptome in the kidneys in aspergillosis, we employed RNA-Seq to obtain single 76-base reads of whole-genome transcripts of murine kidneys on a temporal basis (days 0; uninfected, 1, 2, 3 and 8) during invasive aspergillosis. A total of 6284 transcripts were downregulated, and 5602 were upregulated compared to baseline expression. Gene ontology enrichment analysis identified genes involved in innate and adaptive immune response, as well as iron binding and homeostasis, among others. Our results showed activation of pathogen recognition receptors, e.g., β-defensins, C-type lectins (e.g., dectin-1), Toll-like receptors (TLR-2, TLR-3, TLR-8, TLR-9 and TLR-13), as well as Ptx-3 and C-reactive protein among the soluble receptors. Upregulated transcripts encoding various differentiating cytokines and effector proinflammatory cytokines, as well as those encoding for chemokines and chemokine receptors, revealed Th-1 and Th-17-type immune responses. These studies form a basic dataset for experimental prioritization, including other target organs, to determine the global response of the host against Aspergillus infection.

Molecular Insights Into Development and Virulence Determinants of Aspergilli: A Proteomic Perspective

Aspergillus species are the major cause of health concern worldwide in immunocompromised individuals. Opportunistic Aspergilli cause invasive to allergic aspergillosis, whereas non-infectious Aspergilli have contributed to understand the biology of eukaryotic organisms and serve as a model organism. Morphotypes of Aspergilli such as conidia or mycelia/hyphae helped them to survive in favorable or unfavorable environmental conditions. These morphotypes contribute to virulence, pathogenicity and invasion into hosts by excreting proteins, enzymes or toxins. Morphological transition of Aspergillus species has been a critical step to infect host or to colonize on food products. Thus, we reviewed proteins from Aspergilli to understand the biological processes, biochemical, and cellular pathways that are involved in transition and morphogenesis. We majorly analyzed proteomic studies on A. fumigatus, A. flavus, A. terreus, and A. niger to gain insight into mechanisms involved in the transition from conidia to mycelia along with the role of secondary metabolites. Proteome analysis of morphotypes of Aspergilli provided information on key biological pathways required to exit conidial dormancy, consortia of virulent factors and mycotoxins during the transition. The application of proteomic approaches has uncovered the biological processes during development as well as intermediates of secondary metabolite biosynthesis pathway. We listed key proteins/ enzymes or toxins at different morphological types of Aspergillus that could be applicable in discovery of novel therapeutic targets or metabolite based diagnostic markers.

Methods of Controlling Invasive Fungal Infections Using CD8+ T Cells

Invasive fungal infections (IFIs) cause high rates of morbidity and mortality in immunocompromised patients. Pattern-recognition receptors present on the surfaces of innate immune cells recognize fungal pathogens and activate the first line of defense against fungal infection. The second line of defense is the adaptive immune system which involves mainly CD4+ T cells, while CD8+ T cells also play a role. CD8+ T cell-based vaccines designed to prevent IFIs are currently being investigated in clinical trials, their use could play an especially important role in acquired immune deficiency syndrome patients. So far, none of the vaccines used to treat IFI have been approved by the FDA. Here, we review current and future antifungal immunotherapy strategies involving CD8+ T cells. We highlight recent advances in the use of T cells engineered using a Sleeping Beauty vector to treat IFIs. Recent clinical trials using chimeric antigen receptor (CAR) T-cell therapy to treat patients with leukemia have shown very promising results. We hypothesized that CAR T cells could also be used to control IFI. Therefore, we designed a CAR that targets β-glucan, a sugar molecule found in most of the fungal cell walls, using the extracellular domain of Dectin-1, which binds to β-glucan. Mice treated with D-CAR+ T cells displayed reductions in hyphal growth of Aspergillus compared to the untreated group. Patients suffering from IFIs due to primary immunodeficiency, secondary immunodeficiency (e.g., HIV), or hematopoietic transplant patients may benefit from bioengineered CAR T cell therapy.

Epoxyazadiradione suppresses breast tumor growth through mitochondrial depolarization and caspase-dependent apoptosis by targeting PI3K/Akt pathway

Background

Breast cancer is one of the most commonly diagnosed invasive cancers among women around the world. Among several subtypes, triple negative breast cancer (TNBC) is highly aggressive and chemoresistant. Treatment of TNBC patients has been challenging due to heterogeneity and devoid of well-defined molecular targets. Thus, identification of novel effective and selective agents against TNBC is essential.

Methods

We used epoxyazadiradione to assess the cell viability, mitochondrial potential, ROS level, cell migration, apoptosis and protein expression in cell culture models of TNBC MDA-MB-231 and ER+ MCF-7 breast cancer cells. The molecular mechanism was examined in two different type of breast cancer cells in response to epoxyazadiradione. We have also analyzed the effect of epoxyazadiradione on breast tumor growth using in vivo mice model.

Results

In this study, we for the first time investigated that out of 10 major limonoids isolated from Azadirachta indica, epoxyazadiradione exhibits most potent anti-cancer activity in both TNBC and ER+ breast cancer cells. Epoxyazadiradione induces apoptosis and inhibits PI3K/Akt-mediated mitochondrial potential, cell viability, migration and angiogenesis. It also inhibits the expression of pro-angiogenic and pro-metastatic genes such as Cox2, OPN, VEGF and MMP-9 in these cells. Furthermore, epoxyazadiradione attenuates PI3K/Akt-mediated AP-1 activation. Our in vivo data revealed that epoxyazadiradione suppresses breast tumor growth and angiogenesis in orthotopic NOD/SCID mice model.

Conclusion

Our findings demonstrate that epoxyazadiradione inhibits PI3K/Akt-dependent mitochondrial depolarisation, induces apoptosis and attenuates cell migration, angiogenesis and breast tumor growth suggesting that this compound may act as a potent therapeutic agent for the management of breast cancer.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3876-2) contains supplementary material, which is available to authorized users.

Integrated proteome and HPLC analysis revealed quercetin-mediated inhibition of aflatoxin B1 biosynthesis in Aspergillus flavus

The contamination of aflatoxins in maize or maize-related products synthesized by Aspergillus flavus causes severe economical loss and threat to human health. Use of eco-friendly phytochemicals has shown potential to inhibit secondary metabolites in Aspergillus species. Thus, A. flavus cultured in corn flour (CF) and corn flour with quercetin (CF_Q) was used for protein extraction for proteome analysis using nLC-Q-TOF mass spectrometer. Proteome analysis revealed the expressions of 705 and 843 proteins in CF_Q and CF, respectively. Gene Ontology Slim Categories (GOSC) of CF exhibited major transcriptional factors; involved in acetylation and deacetylation of histone proteins, carbohydrate metabolism, and hydrolase activity, whereas GOSC analysis of CF_Q showed membrane transport activity, including both influx and efflux proteins. cAMP/PKA signaling pathway was observed in CF_Q, whereas MAPK pathway in CF. To quantify biosynthesis of aflatoxin B1 (AFB1) in CF and CF_Q, HPLC analysis at 7, 12, 24 and 48 h was carried out which showed decrease in AFB1 (1%) at 7-24 h in CF_Q. However, remarkable decrease in AFB1 biosynthesis (51%) at 48 h time point was observed. Thus, the present study provided an insight into the mechanism of quercetin-mediated inhibition of aflatoxin biosynthesis in A. flavus and raises the possibility to use quercetin as an anti-aflatoxigenic agent.

Persistence within dendritic cells marks an antifungal evasion and dissemination strategy of Aspergillus terreus

Aspergillus terreus is an airborne human fungal pathogen causing life-threatening invasive aspergillosis in immunocompromised patients. In contrast to Aspergillus fumigatus, A. terreus infections are associated with high dissemination rates and poor response to antifungal treatment. Here, we compared the interaction of conidia from both fungal species with MUTZ-3-derived dendritic cells (DCs). After phagocytosis, A. fumigatus conidia rapidly escaped from DCs, whereas A. terreus conidia remained persisting with long-term survival. Escape from DCs was independent from DHN-melanin, as A. terreus conidia expressing wA showed no increased intracellular germination. Within DCs A. terreus conidia were protected from antifungals, whereas A. fumigatus conidia were efficiently cleared. Furthermore, while A. fumigatus conidia triggered expression of DC activation markers such as CD80, CD83, CD54, MHCII and CCR7, persistent A. terreus conidia were significantly less immunogenic. Moreover, DCs confronted with A. terreus conidia neither produced pro-inflammatory nor T-cell stimulating cytokines. However, TNF-α addition resulted in activation of DCs and provoked the expression of migration markers without inactivating intracellular A. terreus conidia. Therefore, persistence within DCs and possibly within other immune cells might contribute to the low response of A. terreus infections to antifungal treatment and could be responsible for its high dissemination rates.

Proteome Profile of Aspergillus terreus Conidia at Germinating Stage: Identification of Probable Virulent Factors and Enzymes from Mycotoxin Pathways

Aspergillus terreus is an emerging opportunistic fungal pathogen that causes invasive aspergillosis in immunocompromised individuals. The main risk group of individuals for this organism is leukopenic patients, individuals having cancers, bone marrow transplant persons and those who have immunological disorders. The lack of early diagnostic marker for A. terreus and intrinsic resistance to Amphotericin B, further limits the successful therapy of A. terreus-associated infections. The germination of inhaled conidia is the key step to establish successful invasion in host tissues or organs. Thus, profiling of expressed proteins during germination of conidia not only shed light on proteins that are involved in invasion or virulence but may also provide early diagnostic markers. We used nanoLC-Q-TOF to study the proteome of germinating conidia (at 16 h time points) of A. terreus. We observed expression of 373 proteins in germinating conidia of A. terreus. A total of 74 proteins were uncharacterized in the database. The expressed proteins were associated with various processes like cell wall modulation, virulence factors and secondary metabolite biosynthesis. The most abundant proteins were associated with protein biosynthesis, carbohydrate metabolism and unknown functions. Among virulent proteins, mitogen-activated protein kinase (hog1) and mitogen-activated protein kinase (mpkC) are key virulent proteins observed in our study. We observed 7 enzymes from terretonin and 10 enzymes from geodin mycotoxin biosynthesis pathway. Interestingly, we observed expression of terrelysin protein, associated with blood cell lysis. Quantitative RT-PCR analysis showed 26-fold increase in transcripts encoding for dihydrogeodin oxidase and 885-fold for terrelysin gene in germinating conidia in comparison to conidia. Further, we propose that terrelysin protein and secondary metabolite such as geodin could be explored as diagnostic marker for A. terreus-associated infections.

Developments in the diagnosis and treatment of allergic bronchopulmonary aspergillosis

INTRODUCTION

Allergic bronchopulmonary aspergillosis (ABPA) is a complex pulmonary disorder characterized by recurrent episodes of wheezing, fleeting pulmonary opacities and bronchiectasis. It is the most prevalent of the Aspergillus disorders with an estimated five million cases worldwide. Despite six decades of research, the pathogenesis, diagnosis and treatment of this condition remains controversial. The International Society for Human and Animal Mycology has formed a working group to resolve the controversies around this entity. In the year 2013, this group had proposed new criteria for diagnosis and staging, and suggested a treatment protocol for the management of this disorder. Since then, several pieces of new evidence have been published in the investigation and therapeutics of this condition. Areas covered: A non-systematic review of the available literature was performed. We summarize the current evidence in the evaluation and treatment of this enigmatic disorder. We suggest modifications to the existing criteria and propose a new scoring system for the diagnosis of ABPA. Expert commentary: All patients with asthma and cystic fibrosis should routinely be screened for ABPA using A. fumigatus-specific IgE levels. Glucocorticoids should be used as the first-line of therapy in ABPA, and itraconazole reserved in those with recurrent exacerbations and glucocorticoid-dependent disease.

In silico Identification of Potential Peptides or Allergen Shot Candidates Against Aspergillus fumigatus

Aspergillus fumigatus is capable of causing invasive aspergillosis or acute bronchopulmonary aspergillosis, and the current situation is alarming. There are no vaccine or allergen shots available for Aspergillus-induced allergies. Thus, a novel approach in designing of an effective vaccine or allergen shot candidate against A. fumigatus is needed. Using immunoinformatics approaches from the characterized A. fumigatus allergens, we have mapped epitopic regions to predict potential peptides that elicit both Aspergillus-specific T cells and B cell immune response. Experimentally derived immunodominant allergens were retrieved from www.allergen.org. A total of 23 allergenic proteins of A. fumigatus were retrieved. Out of 23 allergenic proteins, 13 of them showed high sequence similarity to both human and mouse counterparts and thus were eliminated from analysis due to possible cross-reactivity. Remaining allergens were subjected to T cell (major histocompatibility complex class I and II alleles) and B cell epitope prediction using immune epitope database analysis resource. Only five allergens have shown a common B and T cell epitopic region between human and mouse. They are Asp f1 {147-156 region (RVIYTYPNKV); Mitogillin}, Asp f2 {5-19 region (LRLAVLLPLAAPLVA); Hypothetical protein}, Asp f5 {305-322 region (LNNYRPSSSSLSFKY); Metalloprotease}, Asp f17 {98-106 region (AANAGGTVY); Hypothetical protein}, and Asp f34 {74-82 region (YIQDGSLYL); PhiA cell wall protein}. The epitopic region from these five allergenic proteins showed potential for development of single peptide- or multipeptide-based vaccine or allergen shots for experimental prioritization.

Are allergic fungal rhinosinusitis and allergic bronchopulmonary aspergillosis lifelong conditions?

Aspergillus fumigatus can cause several allergic disorders including Aspergillus-sensitized asthma, allergic bronchopulmonary aspergillosis (ABPA), and allergic fungal rhinosinusitis (AFRS). ABPA is an immunological pulmonary disorder caused by allergic reactions mounted against antigens of A. fumigatus colonizing the airways of patients with asthma (and cystic fibrosis). Allergic bronchopulmonary mycosis is an allergic fungal airway disease caused by thermotolerant fungi other than A. fumigatus On the other hand, AFRS is a type of chronic rhinosinusitis that is also a result of hypersensitivity reactions to the presence of fungi that become resident in the sinuses. The pathogenesis of ABPA and AFRS share several common features, and in fact, AFRS can be considered as the upper airway counterpart of ABPA. Despite sharing similar immunopathogenetic features, the simultaneous occurrence of the two disorders is uncommon. Due to the lacuna in understanding of the causative mechanisms, and deficiencies in the diagnosis and treatment, these disorders unfortunately are lifelong illnesses. This review provides an overview of the pathogenesis, diagnosis, and long-term outcomes of both these disorders.

Nano-LC-Q-TOF Analysis of Proteome Revealed Germination of Aspergillus flavus Conidia is Accompanied by MAPK Signalling and Cell Wall Modulation

Aspergillus flavus is the second most leading cause of aspergillosis. The ability of A. flavus to adapt within the host environment is crtical for its colonization. Onset of germination of conidia is one of the crucial events; thus, in order to gain insight into A. flavus molecular adaptation while germination, protein profile of A. flavus was obtained. Approximately 82 % of conidia showed germination at 7 h; thus, samples were collected followed by protein extraction and subjected to nLC-Q-TOF mass spectrometer. Q-TOF data were analysed using Protein Lynx Global Services (PLGS 2.2.5) software. A total of 416 proteins were identified from UniProt Aspergillus species database. Orthologues of A. flavus was observed in A. fumigatus, A. niger, A. terreus, A. oryzae, etc. Proteins were further analysed in NCBI database, which showed that 27 proteins of A. flavus are not reported in UniProt and NCBI database. Functional characterization of proteins resulted majorly to cell wall synthesis and degradation, metabolisms (carbohydrate and amino acid metabolism), protein synthesis and degradation. Proteins/enzymes associated with aflatoxin biosynthesis were observed. We also observed Dicer-like proteins 1, 2 and autophagy-related proteins 2, 9, 18, 13, 11, 22. Expression of protein/enzymes associated with MAPK signalling pathway suggests their role during the germination process. Overall, the data present a catalogue of proteins/enzymes involved in the germination of A. flavus conidia and could also be applied to other Aspergillus species.

Allergic Bronchopulmonary Aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA), a progressive fungal allergic lung disease, is a common complication of asthma or cystic fibrosis. Although ABPA has been recognized since the 1950s, recent research has underscored the importance of Th2 immune deviation and granulocyte activation in its pathogenesis. There is also strong evidence of widespread under-diagnosis due to the complexity and lack of standardization of diagnostic criteria. Treatment has long focused on downregulation of the inflammatory response with prolonged courses of oral glucocorticosteroids, but more recently concerns with steroid toxicity and availability of new treatment modalities has led to trials of oral azoles, inhaled amphotericin, pulse intravenous steroids, and subcutaneously-injected anti-IgE monoclonal antibody omalizumab, all of which show evidence of efficacy and reduced toxicity.

In silico Analysis Revealed High-risk Single Nucleotide Polymorphisms in Human Pentraxin-3 Gene and their Impact on Innate Immune Response against Microbial Pathogens

Pentraxin-3 (PTX-3) protein is an evolutionary conserved protein that acts as a soluble pattern-recognition receptor for pathogens and plays important role in innate immune response. It recognizes various pathogens by interacting with extracellular moieties such as glactomannan of conidia (Aspergillus fumigatus), lipopolysaccharide of Pseudomonas aeruginosa, Streptococcus pneumonia and Salmonella typhimurium. Thus, PTX-3 protein helps to clear these pathogens by activating downstream innate immune process. In this study, computational methods were used to analyze various non-synonymous single nucleotide polymorphisms (nsSNPs) in PTX-3 gene. Three different databases were used to retrieve SNP data sets followed by seven different in silico algorithms to screen nsSNPs in PTX-3 gene. Sequence homology based approach was used to identify nsSNPs. Conservation profile of PTX-3 protein amino acid residues were predicted by ConSurf web server. In total, 10 high-risk nsSNPs were identified in pentraxin-domain of PTX-3 gene. Out of these 10 high-risk nsSNPs, 4 were present in the conserved structural and functional residues of the pentraxin-domain, hence, selected for structural analyses. The results showed alteration in the putative structure of pentraxin-domain. Prediction of protein–protein interactions analysis showed association of PTX-3 protein with C1q component of complement pathway. Different functional and structural residues along with various putative phosphorylation sites and evolutionary relationship were also predicted for PTX-3 protein. This is the first extensive computational analyses of pentraxin protein family with nsSNPs and will serve as a valuable resource for future population based studies.