Fungal Polysaccharides Research Articles

The Complexity of Fungal β-Glucan in Health and Disease: Effects on the Mononuclear Phagocyte System.

β-glucan, the most abundant fungal cell wall polysaccharide, has gained much attention from the scientific community in the last few decades for its fascinating but not yet fully understood immunobiology. Study of this molecule has been motivated by its importance as a pathogen-associated molecular pattern upon fungal infection as well as by its promising clinical utility as biological response modifier for the treatment of cancer and infectious diseases. Its immune effect is attributed to the ability to bind to different receptors expressed on the cell surface of phagocytic and cytotoxic innate immune cells, including monocytes, macrophages, neutrophils, and natural killer cells. The characteristics of the immune responses generated depend on the cell types and receptors involved. Size and biochemical composition of β-glucans isolated from different sources affect their immunomodulatory properties. The variety of studies using crude extracts of fungal cell wall rather than purified β-glucans renders data difficult to interpret. A better understanding of the mechanisms of purified fungal β-glucan recognition, downstream signaling pathways, and subsequent immune regulation activated, is, therefore, essential not only to develop new antifungal therapy but also to evaluate β-glucan as a putative anti-infective and antitumor mediator. Here, we briefly review the complexity of interactions between fungal β-glucans and mononuclear phagocytes during fungal infections. Furthermore, we discuss and present available studies suggesting how different fungal β-glucans exhibit antitumor and antimicrobial activities by modulating the biologic responses of mononuclear phagocytes, which make them potential candidates as therapeutic agents.

Protective properties of combined fungal polysaccharides from Cordyceps sinensis and Ganoderma atrum on colon immune dysfunction

In vivo an ecological network of polysaccharides utilization by gut microbiota is not only an intense competition but also an impressive cooperation pattern. The present study evaluated the in vivo protective effect of combined fungal polysaccharides (CFP) from Cordyceps sinensis and Ganoderma atrum on colon immune dysfunction, induced by 150mg/kg cyclophosphamide (CP). The results showed that C. sinensis polysaccharides (CSP) significantly promoted microbial-derived butyrate to improve histone h3 acetylation mediating regulatory T (Treg) cell specific Foxp3, as well as significantly restored CP-induced elevation of interleukin (IL)-17 and IL-21. Additionally, G. atrum polysaccharides (PSG) significantly down-regulated MyD88, as well as significantly increased IL-10 and TGF-β3. Furthermore, CFP balanced the disequilibrium of cytokines secretion and Foxp3/RORγt ratio related Treg/T helper 17 (Th17) balance, as well as down-regulated the TLR-mediated inflammatory signaling pathway and promoted secretory immunoglobulin A (sIgA) secretion to suppress colonic inflammation. Therefore, our results typically contribute to understand the in vivo immunoregulatory function of fungal polysaccharides compounds, involving microbial-associated inflammatory signals and specific metabolic products.

Functional polysaccharide Lentinan suppresses human breast cancer growth via inducing autophagy and caspase-7-mediated apoptosis

The aim of this study was to evaluate the direct antitumor activity of edible fungal polysaccharide Lentinan, rather than as a host defence potentiator, on human breast cancer and investigate its underlying mechanisms. The present results revealed that there were 45.46% and 59.16% of inhibitory rate after Lentinan treatment in MCF-7 cells and tumor-bearing athymic nude mice, respectively. Annexin V-FITC/PI, H&E staining and TUNEL assay showed that Lentinan induced cell apoptosis which accompanied with abundant activated caspase-7, increased cytosol cytochrome c and Bax/Bcl-2. Unexpectedly, we firstly demonstrated that Lentinan could stimulate cell autophagy according to the detection of autophagosomes and autophagic flux. Pretreatment with autophagy inhibitors decreased Lentinan-induced cells death. These findings provided new insight into the mechanisms of Lentinan-antitumor effect and contributed to its development in functional foods and cancer therapy.

8. Evaluation of Snow Fungus Polysaccharides on benzo[a]pyrene-induced DNA Damage

Snow fungus, Tremella fuciformis, has been demonstrated to have numerous health benefits including purported chemopreventive properties due to free radical-scavenging ability. Protective effects derived from snow fungus polysaccharides are evaluated on Chinese hamster lung fibroblasts (CCL-39) exposed to carcinogen benzo[a]pyrene known to cause free radical formation and oxidative stress to cells.
 In this experiment, it was hypothesized that the naturally occurring polysaccharides in snow fungus are able to protect against or reduce oxidative stress-induced DNA damage. Polysaccharides were isolated through an alkaline extraction and in-vitro digestion. DNA damage was measured using the single-cell gel electrophoresis comet assay after exposure to benzo[a]pyrene and polysaccharide extract to lung fibroblasts. Results were calculated using the mean and standard deviation data of tail length and area, respectively. Each damaged cell was measured and analyzed through ImageJ Editing Software. The results indicate a promising trend which depict snow fungus polysaccharides yielding lower levels of DNA damage compared to cells exposed to benzo[a]pyrene and compared to the negative control (phosphate buffered saline and Dulbecco’s cell medium). This study suggests polysaccharides from Tremella fuciformis could truly prevent cellular DNA damage by protecting against oxidative stress.

Theoretical and experimental substantiation of a fungal therapeutic drug with immunomodulating and antitumor action according to the authors’ prescription

The article is devoted to a promising direction in pharmacological mycology and biotechnology, namely the use of Basidiomycetes as a biologically active substance for preparation of pharmaceuticals. The anticancer and immunostimulating properties of Basidiomycetes result from the structural characteristics of the polysaccharides: the presence of β-(1 → 3) connections in the main chain and an additional β-(1 → 6) branched part of glucans. Attention is focused on Shiitake mushrooms (Lentinula edodes) as a unique biosystem with a strong ability to be involved in the regulatory mechanism of human immunomodulation. The purpose of the theoretical and experimental study is development of a pharmaceutical preparation from Shiitake biomass (including its immune cells), the effectiveness of which is considered from the standpoint of the chemistry of natural compounds. Having a 3000-year history of cultivation and application, this mushroom is again of interest to scientists around the world because of investigation into its therapeutic and prophylactic potentials. For the first time, the biotechnological method of cultivating L. edodes biomass was developed with the use of deep cultivation, adapted to the plant raw material base of Ukraine. Malt wort was used as a nutrient medium without processing Humulus lupulus. The analysis of research and preclinical studies of specific activity of the designated biosystem showed a steady increase in human immune status, particularly the antitumor status. This gives special relevance to the evaluation of the properties of the designated biosystem in order to further develop the corresponding fungo-therapeutic immunomodulatory and antitumor drug. According to the results of technological research: physico-chemical characteristics of Shiitake biomass dry powder (including crystallographic) were studied; the possibility of its tableting using only antifriction auxiliaries was substantiated; the optimum technology of tablet manufacturing with an operating name "Shitavit" was presented, an integrated approach to its creation was presented, the qualitative and quantitative composition of the drug was experimentally developed. The direct compression method was rejected due to unsatisfactory performance of all samples of tablets. The chosen technology of using preliminary granulation and the possibility of short-term contact of the L. edodes dry powder with a granulation liquid and an adjustable temperature regime allows all the properties of the biologically active substances of the designated raw material to be preserved. The research results for all series of the designated object showed relative stability of parameters for all indicators in laboratory samples. The information presented in this article is a guide to further research, necessary for a better understanding of the healing properties of fungal polysaccharides, increasing the use of broad-spectrum fungi-based preparations,leading to improvement of the quality of human life.

Pullulan as a potent green inhibitor for corrosion mitigation of aluminum composite: Electrochemical and surface studies

This work emphasizes the corrosion inhibition ability of pullulan, an environmentally benign fungal polysaccharide on acid corrosion of 6061Aluminum-15%(v) SiC(P) composite material (Al-CM). The electrochemical measurements such as potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) studies were carried out for the corrosion inhibition studies. Conditions were optimized to obtain maximum inhibition efficiency, by performing the experiment at varying concentrations of inhibitor, in the temperature range of 308K- 323K. Surface morphology studies were done to reaffirm the adsorption of inhibitor on the surface of composite material. Pullulan acted as mixed type of inhibitor with a maximum efficiency of 89% at 303K for the addition of 1.0 gL−1 of inhibitor. Evaluation of kinetic and thermodynamic parameters revealed that inhibitor underwent physical adsorption onto the surface of Al-CM and obeyed Freundlich adsorption isotherm. The surface characterization like SEM-EDX, AFM confirmed the adsorption of pullulan molecule. Pullulan can be considered as effective, eco friendly green inhibitor for the corrosion control of Al-CM.

Active-site copper reduction promotes substrate binding of fungal lytic polysaccharide monooxygenase and reduces stability

Lytic polysaccharide monooxygenases (LPMOs) are a class of copper-containing enzymes that oxidatively degrade insoluble plant polysaccharides and soluble oligosaccharides. Upon reductive activation, they cleave the substrate and promote biomass degradation by hydrolytic enzymes. In this study, we employed LPMO9C from Neurospora crassa, which is active toward cellulose and soluble β-glucans, to study the enzyme-substrate interaction and thermal stability. Binding studies showed that the reduction of the mononuclear active-site copper by ascorbic acid increased the affinity and the maximum binding capacity of LPMO for cellulose. The reduced redox state of the active-site copper and not the subsequent formation of the activated oxygen species increased the affinity toward cellulose. The lower affinity of oxidized LPMO could support its desorption after catalysis and allow hydrolases to access the cleavage site. It also suggests that the copper reduction is not necessarily performed in the substrate-bound state of LPMO. Differential scanning fluorimetry showed a stabilizing effect of the substrates cellulose and xyloglucan on the apparent transition midpoint temperature of the reduced, catalytically active enzyme. Oxidative auto-inactivation and destabilization were observed in the absence of a suitable substrate. Our data reveal the determinants of LPMO stability under turnover and non-turnover conditions and indicate that the reduction of the active-site copper initiates substrate binding.

Lytic xylan oxidases from wood-decay fungi unlock biomass degradation.

Wood biomass is the most abundant feedstock envisioned for the development of modern biorefineries. However, the cost-effective conversion of this form of biomass into commodity products is limited by its resistance to enzymatic degradation. Here we describe a new family of fungal lytic polysaccharide monooxygenases (LPMOs) prevalent among white-rot and brown-rot basidiomycetes that is active on xylans-a recalcitrant polysaccharide abundant in wood biomass. Two AA14 LPMO members from the white-rot fungus Pycnoporus coccineus substantially increase the efficiency of wood saccharification through oxidative cleavage of highly refractory xylan-coated cellulose fibers. The discovery of this unique enzyme activity advances our knowledge on the degradation of woody biomass in nature and offers an innovative solution for improving enzyme cocktails for biorefinery applications.

Production of functionalised chitins assisted by fungal lytic polysaccharide monooxygenase

The gene CCT67099 from Fusarium fujikuroi was shown to encode a novel enzyme from the Lytic Polysaccharide Monooxygenase (LPMO) Family AA11.

Protein chip of Boletus speciosus Frost Polysaccharide Revealed the Molecular Mechanism of Antitumor and Immunostimulatory Activities on Macrophages

The polysaccharide of Boletus speciosus Frost has a backbone of (1→4)-α-L-mannopyranose residues, which branched at O-6 and the branches mainly comprised of (a→1)-α-D-galactopyranose residue. To find out signaling transduction pathways that mediate the effect of the polysaccharide of Boletus speciosus Frost on macrophages, the polysaccharide of B. speciosus Frost was used to stimulate the macrophages and 200 cytokines were detected with the help of a protein chip. Further analysis of the result revealed 48 up-regulated and 73 down-regulated cytokines. All cytokines were imported into the KEGG Pathway Database and NCBI to identify the signaling pathway and biological functions involved, respectively. The results showed that the cytokines fulfilled valuable functions in the JAK-STAT signaling pathway and NF-kappa B signaling pathway. This study thus revealed that the edible fungus polysaccharides could stimulate immune cells to secrete immune factors, which could provide a scientific basis for targeting sugar immunization preparations.

Catalytic Mechanism of Fungal Lytic Polysaccharide Monooxygenases Investigated by First-Principles Calculations.

Lytic polysaccharide monooxygenases (LPMOs) are Cu-containing enzymes that facilitate the degradation of recalcitrant polysaccharides by the oxidative cleavage of glycosidic bonds. They are gaining rapidly increasing attention as key players in biomass conversion, especially for the production of second-generation biofuels. Elucidation of the detailed mechanism of the LPMO reaction is a major step toward the assessment and optimization of LPMO efficacy in industrial biotechnology, paving the way to utilization of sustainable fuel sources. Here, we used density functional theory calculations to study the reaction pathways suggested to date, exploiting a very large active-site model for a fungal AA9 LPMO and using a celloheptaose unit as a substrate mimic. We identify a copper oxyl intermediate as being responsible for H-atom abstraction from the substrate, followed by a rapid, water-assisted hydroxyl rebound, leading to substrate hydroxylation.

Function and Biosynthesis of Cell Wall α-1,3-Glucan in Fungi.

Although α-1,3-glucan is a major cell wall polysaccharide in filamentous fungi, its biological functions remain unclear, except that it acts as a virulence factor in animal and plant pathogenic fungi: it conceals cell wall β-glucan on the fungal cell surface to circumvent recognition by hosts. However, cell wall α-1,3-glucan is also present in many of non-pathogenic fungi. Recently, the universal function of α-1,3-glucan as an aggregation factor has been demonstrated. Applications of fungi with modified cell wall α-1,3-glucan in the fermentation industry and of in vitro enzymatically-synthesized α-1,3-glucan in bio-plastics have been developed. This review focuses on the recent progress in our understanding of the biological functions and biosynthetic mechanism of cell wall α-1,3-glucan in fungi. We briefly consider the history of studies on α-1,3-glucan, overview its biological functions and biosynthesis, and finally consider the industrial applications of fungi deficient in α-1,3-glucan.

LC3-Associated Phagocytosis Is Required for Dendritic Cell Inflammatory Cytokine Response to Gut Commensal Yeast Saccharomyces cerevisiae.

The human fungal microbiota known as mycobiota is increasingly recognized as a critical factor in human gut health and disease. Non-pathogenic commensal yeasts such as Saccharomyces cerevisiae promote homeostasis in the gut, whereas dysbiosis of the gut mycobiota is associated with inflammation. Glycan-binding receptors (lectins) are key host factors in host–mycobiota interaction in the gut. They are expressed on immune cells such as dendritic cells (DCs) and recognize fungal polysaccharides. This interaction is imperative to mount appropriate immune responses for immune homeostasis in the gut as well as clearance of fungal pathogens. Recent studies demonstrate that microtubule-associated protein light-chain 3 (LC3)-associated phagocytosis (LAP) is involved in lectin–fungi interactions. Yet, the biological impact of LAP on the lectin function remains largely elusive. In this report, we demonstrate that in mouse LAP is linked to dendritic cell-associated lectin 2 (Dectin-2), a C-type lectin specific to fungal α-mannan polysaccharide. We found that mouse Dectin-2 recognizes commensal yeast S. cerevisiae and Kazachstania unispora. Mouse bone marrow-derived DCs (BMDCs) produced inflammatory cytokines TNFα and IL-1β in response to the yeasts in a Dectin-2 and spleen tyrosine kinase (Syk)-dependent manner. We found that S. cerevisiae and K. unispora induced LAP in mouse BMDCs upon internalization. Furthermore, LC3 was activated by stimulation of BMDCs with the yeasts in a Dectin-2 and Syk-dependent manner. To address the biological impact of LAP on Dectin-2 yeast interaction, we established a knock-in mouse strain (Atg16L1E230, thereafter called E230), which BMDCs exhibit autophagy-active and LAP-negative phenotypes. When stimulated with yeasts, E230 BMDCs produced significantly less amounts of TNFα and IL-1β. Taken together, we revealed a novel link between Dectin-2 and LAP that enables host immune cells to respond to mycobiota.

Saccharides of ectomycorrhizal fungal sclerotia as sources of forest soil polysaccharides

ABSTRACTThe neutral monosaccharide composition of forest soils differs from that of non-forest soils suggesting there is an accumulation of microbial saccharides. Ectomycorrhizal (ECM) fungi can be responsible as the fungi are typical in forest soils. We investigated neutral saccharides of ECM fungal sclerotia to determine what part it might play in the origin of forest soil polysaccarides. Sclerotial grain (SG) was collected from the O, A1 and A2 horizons of a soil of subalpine forest of Mt. Ontake, central Japan. Neutral saccharides in soil and SG were analyzed by two step hydrolysis with sulfuric acid and gas-chromatography of alditol acetate derivatives. Saccharides accounted for 6.0−16% of the SG by carbon content. The SG contained predominantly easily hydrolysable (EH)-glucose, which accounted for 75–85% of the composition depending on grain size and the soil horizon, followed by mannose (7.7−15%), galactose (2.2−4.8%) and non-easily hydrolysable (NEH)-glucose (1.7−6.1%). The SG contained all of these sugars irrespective of its size. The SG collected from the A1 and A2 horizons contained all sugar components found in that from the O horizon, except for fucose in that from A2 horizon. The monosaccharide composition of SG indicates that accumulation of ECM fungal sclerotial polysaccharides might have been responsible for enlarging the molar ratios of (galactose + mannose) /(arabinose + xylose) and EH-glucose/NEH-glucose of forest soils. The proportions of SG saccharides relative to soil saccharides were 3.6, 1.2, and 0.83% for the O, A1 and A2 horizons, respectively. These levels of the proportion are considerable as ECM fugal sclerotia are the products of a limited species among hundreds and thousands of microbial species inhabiting forest soils. The sclerotia forming ECM fungal species such as Cenococcum geophilum may be key sources of forest soil polysaccharides.

Immune Recognition of Fungal Polysaccharides.

The incidence of fungal infections has dramatically increased in recent years, in large part due to increased use of immunosuppressive medications, as well as aggressive medical and surgical interventions that compromise natural skin and mucosal barriers. There are relatively few currently licensed antifungal drugs, and rising resistance to these agents has led to interest in the development of novel preventative and therapeutic strategies targeting these devastating infections. One approach to combat fungal infections is to augment the host immune response towards these organisms. The polysaccharide-rich cell wall is the initial point of contact between fungi and the host immune system, and therefore, represents an important target for immunotherapeutic approaches. This review highlights the advances made in our understanding of the mechanisms by which the immune system recognizes and interacts with exopolysaccharides produced by four of the most common fungal pathogens: Aspergillus fumigatus, Candida albicans, Cryptococcus neoformans, and Histoplasma capsulatum. Work to date suggests that inner cell wall polysaccharides that play an important structural role are the most conserved across diverse members of the fungal kingdom, and elicit the strongest innate immune responses. The immune system senses these carbohydrates through receptors, such as lectins and complement proteins. In contrast, a greater diversity of polysaccharides is found within the outer cell walls of pathogenic fungi. These glycans play an important role in immune evasion, and can even induce anti-inflammatory host responses. Further study of the complex interactions between the host immune system and the fungal polysaccharides will be necessary to develop more effective therapeutic strategies, as well as to explore the use of immunosuppressive polysaccharides as therapeutic agents to modulate inflammation.

A comparative study on the activity of fungal lytic polysaccharide monooxygenases for the depolymerization of cellulose in soybean spent flakes

Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes capable of the oxidative breakdown of polysaccharides. They are of industrial interest due to their ability to enhance the enzymatic depolymerization of recalcitrant substrates by glycoside hydrolases. In this paper, twenty-four lytic polysaccharide monooxygenases (LPMOs) expressed in Trichoderma reesei were evaluated for their ability to oxidize the complex polysaccharides in soybean spent flakes, an abundant and industrially relevant substrate. TrCel61A, a soy-polysaccharide-active AA9 LPMO from T. reesei, was used as a benchmark in this evaluation. In total, seven LPMOs demonstrated activity on pretreated soy spent flakes, with the products from enzymatic treatments evaluated using mass spectrometry and high performance anion exchange chromatography. The hydrolytic boosting effect of the top-performing enzymes was evaluated in combination with endoglucanase and beta-glucosidase. Two enzymes (TrCel61A and Aspte6) showed the ability to release more than 36% of the pretreated soy spent flake glucose – a greater than 75% increase over the same treatment without LPMO addition.

The methodology of creating a vaccine against candidiasis

Candidiasis is one of the most common diseases of our time. For many years to treat candidiasis the same antifungal drugs, to which the fungi gradually develop resistance, have been used. One of the ways to solve the problem of effective treatment of candidiasis is to use vaccines, which have a number of significant advantages compared to other antifungal drugs. Currently, there are no vaccines against candidiasis at the pharmaceutical market.Aim. To substantiate the general concept for creation of a new vaccine based on Candida fungi.Materials and methods. Development of a new vaccine should be combined on a common methodological approach to pharmaceutical development taking into account the requirements for a dosage form. In order to determine the general concept for creation of a new vaccine the following areas of research have been outlined: development of a new vaccine based on inactivated cells of Candida genus fungi and creation of a new vaccine for the renewal of proteins and polysaccharides of fungi of Candida genus fungi.Results. To provide the effectiveness and safety of the vaccine all pharmaceutical and technological factors that affect the vaccine should be theoretically and experimentally substantiated. They include the nature and the amount of active substances, technological parameters for preparation and mixing of active substances, the physicochemical and biological properties of active substances and excipients, equipment. In order to provide the therapeutic effectiveness of the vaccine the biopharmaceutical studies to determine antibody titers and efficacy in the prevention and treatment of candidal infection were conducted.Conclusions. Thus, on the basis of the universal methodological approach to pharmaceutical development the methodology has been substantiated; the plan for experimental studies on creating the solution of the vaccine for injection to prevent and treat candidiasis on the basis of fungal cells of Candida genus has been developed.

Effect of edible fungal polysaccharides on improving influenza vaccine protection in mice

ABSTRACTFungal polysaccharides have shown broad spectrum of biological activities, including anti-inflammatory, ant-oxidative and improve immunity. However, oral administration of fungal polysaccharides for rendering the conventional vaccine against influenza virus has been reported rarely. Here, we investigated the potential of fungal polysaccharides in enhancing the influenza vaccine efficacy in a mouse model. Mice were immunized with inactivated H1N1 (A/PR8/1934) influenza vaccine combined with oral polysaccharides lentinan, tremellan, pachymaran and a mixture of the three. The results showed that mice in the polysaccharides/vaccine groups had reduced morbidity, improved viral clearance, and recovered faster than the mice receiving the conventional vaccine only after infection. This effect could be attributed to the increased levels of virus-specific serum antibody IgG and decreased levels of inflammatory cytokine IFN-γ in the lung tissue. Our finding suggests that taking fungal polysaccharides orally might be useful for improving the efficacy of conventional inactive influenza vaccines.

Aberrant staining with Grocott's methenamine silver: utility beyond fungal organisms

Historically, Grocott's methenamine silver (GMS) stain has been used in cytopathology to highlight Pneumocystis jiroveci and other fungal organisms. Several nonfungal organisms, however, can show distinct GMS staining patterns that are important to recognize. We prospectively and retrospectively identified nonfungal pathogenic organisms on GMS-stained liquid-based and cytospin preparations of respiratory cytologic specimens. The organisms included parasitic worms, viruses, and assorted bacteria. Nine cases were identified, including two cases each of Strongyloides stercoralis, Cytomegalovirus, Mycobacterium tuberculosis, Nocardia species, as well as one case of anthrax-like Bacillus cereus. The nonfungal organisms had silver deposition in varying locations including the internal organs and/or cuticle of Strongyloides stercoralis larvae, the intranuclear inclusions of Cytomegalovirus infected cells, the surfaces of partially acid-fast Nocardia species and acid-fast Mycobacterium tuberculosis, and the cell walls and central endospores of Bacillus cereus. In 3 of the 9 cases, organisms were not clinically suspected. It was the aberrant GMS staining that pointed to the diagnosis and led to the performance of the definitive stain, culture, or other test. GMS is a chromic acid, sodium bisulfate stain that precipitates silver ions in fungal polysaccharide walls, producing the characteristic black stain on light microscopy. It is helpful to recognize aberrant GMS staining to avoid misdiagnosis of fungal elements. GMS stains several nonfungal human pathogens and may be a particularly useful diagnostic aid when the infectious condition is not clinically suspected or the number of organisms is sparse and otherwise difficult to visualize by routine staining methods.

Lung eosinophil recruitment in response to Aspergillus fumigatus is correlated with fungal cell wall composition and requires γδ T cells

The differential recognition of fungal cell wall polysaccharides that program innate and adaptive immunity to the human opportunistic fungal pathogen Aspergillus fumigatus has been a focus of considerable interest. In a mouse model of fungal conidia aspiration, decreased relative levels of cell wall core carbohydrates β-1,3-glucan to chitin in A. fumigatus isolates and mutant strains were correlated with increased airway eosinophil recruitment. In addition, an increase in fungal surface chitin exposure induced by the β-1,3-glucan synthesis-targeting drug caspofungin was associated with increased murine airway eosinophil recruitment after a single challenge of conidia. The response to increased A. fumigatus chitin was associated with increased transcription of IL-17A after a single aspiration, although this cytokine was not required for eosinophil recruitment. Rather, both RAG1 and γδ T cells were required, suggesting that this subset of innate-like lymphocytes may be an important regulator of potentially detrimental type 2 immune responses to fungal inhalation and infection.