Rhizoglyphus robini, a pest mite of saffron, is unable to resist extracellular ice formation.

The saffron mite, Rhizoglyphus robini Claparède (Acari, Astigmata: Acaridae), is one of the most important pests of saffron-producing regions in Iran. It causes yellowing and decreases saffron growth, and finally it destroys the bulbs. In this research, the cold tolerance and supercooling point (SCP) of the saffron mite were measured in three populations and two temperature regimes. Our results showed that the mean SCP of the saffron mite was approximately -14.6 °C without significant difference among the populations. On the contrary, acclimation of the mites significantly decreased their SCP to a mean of approximately -16.5 °C. Exposure of the mites for 24 h to 0 and -2.5 °C had no significant effect on the survival of the mites but when the mites were exposed to -5.0 °C for 24 h, survival of the three populations reached the lowest level of roughly 60%. By 24-h exposure to -7.5 °C, survival of the mites was almost negligible. As a large proportion of mortality was observed above the SCP, and LT50 > SCP, it can be inferred that the saffron mite is likely a chill-susceptible species. This suggests that the saffron mite lacks the ability to withstand extracellular ice formation. Overall, the results of the current study suggest no significant physiological differences between populations of the saffron mite.

Small-scale genetic structure of populations of the bulb mite Rhizoglyphus robini.

Bulb mites are an economically significant pest of subterranean parts of plants and a versatile laboratory animal. However, the genetic structure of their populations remains unknown. To fill this gap in our knowledge of their biology, we set up a field experiment in which we allowed mites to colonize onion bulbs, and then determined the genetic structure of colonisers based on a panel of microsatellite loci. We found moderate but significant population structure among sites separated by ca. 20 m (FST range 0.03-0.21), with 7% of genetic variance distributed among sites. Allelic richness within some bulbs was nearly as high as that in the total population, suggesting that colonisation of bulbs was not associated with strong population bottlenecks. The significant genetic structure we observed over small spatial scales seems to reflect limited dispersal of mites in soil.

First identification of Tyrophagus curvipenis (Acari: Acaridae) and pathogen detection in Apis mellifera colonies in the Republic of Korea.

Mites of the genus Tyrophagus (Acari: Acaridae) are among the most widely distributed mites. The species in this genus cause damage to stored products and crops, and pose a threat to human health. However, the influence of Tyrophagus spp. in apiculture remains unknown. In 2022, a study focusing on the identification of Tyrophagus species within five apiaries was conducted in Chungcheongnam Province, Republic of Korea. Its specific objective was to investigate the presence of Tyrophagus mites in response to the reported high mortality of honey bee colonies in this area. Morphological identification and phylogenetic analysis using the mitochondrial gene cytochrome-c oxidase subunit 1 (CO1) confirmed for the first time the presence of the mite species Tyrophagus curvipenis in a honey bee colony in the Republic of Korea. Two honey bee pathogens were detected in the mite, a viral pathogen (deformed wing virus, DWV) and a protozoal pathogen (Trypanosoma spp.). The presence of the two honey bee pathogens in the mite suggests that this mite could contribute to the spread of related honey bee diseases. However, the direct influence of the mite T. curvipenis on honey bee health remains unknown and should be further investigated.

Effects of in-house and commercial extracts of the allergenic mite Tyrophagus putrescentiae on murine and human cell responses.

Mites are among the major sources of domestic and occupational allergens worldwide, and continuous exposure to these allergens leads to chronic airway inflammation. One of the most allergenic species is the storage mite Tyrophagus putrescentiae (Schrank). Protein extracts are produced from this mite for tests that help the clinical diagnosis (via prick test), treatment, and monitoring of disease progression in patients who had positive results for allergic reactions. Therefore, the aim of the present study was to evaluate the cell viability of RAW 264.7 and L929 cells when exposed to in-house raw protein extracts of T. putrescentiae compared to a commercial product, as well as quantify TNF-α secretion by RAW 264.7. Additionally, this study quantified the effect of these extracts in IgE secretion in total blood of people affected by this mite. The study found similarity between the in-house extract and the commercial extract as they had equivalent TNF-α secretion. Additionally, viabilities of RAW 264.7 and L929 exposed to the in-house extract were compatible with viabilities of cells exposed to the commercial extract, with no cytotoxicity at the concentrations tested. Results corroborated the hypothesis that the extract produced in-house would be equivalent to the commercial extract in allergic patients when the IgE was quantified. This study is the first to show the cytotoxicity of T. putrescentiae extracts, and to provide a quantitative analysis of TNF-α and IgE.

Predatory mite Amblyseius orientalis prefers egg stage and low density of Carpoglyphus lactis prey.

Amblyseius orientalis (Ehara) (Acari: Phytoseiidae) is an effective predatory mite for spider mite control on fruit trees in China. In recent decades, it has been produced massively at a commercial natural enemy producer, feeding on the storage mite Carpoglyphus lactis (L.). In the predator production process, the ratio of predatory mites to their prey was found to be critical for the population increase of A. orientalis in large-scale rearings. In this study, we investigated the predatory capacity of A. orientalis on various developmental stages of the prey C. lactis, and the effect of prey numbers on predator reproduction. The maximum predation rate of A. orientalis adults on C. lactis adults was 2.21 per day at the lowest density of five prey adults, and on C. lactis eggs it was 45.07 at the highest density of 60 prey eggs. The preference index Ci of A. orientalis on C. lactis eggs and adults was 0.4312 and - 0.9249, respectively, suggesting that A. orientalis preferred eggs to adults. Amblyseius orientalis could reproduce when it preyed on either eggs or deutonymphs of C. lactis. However, the fecundity of the predatory mites is not always proportional to the provided prey number. Higher density of prey deutonymphs resulted in lower fecundity, whereas more prey eggs resulted in higher fecundity of A. orientalis. Therefore, our study indicated that the choice of suitable density and developmental stage of prey can significantly improve A. orientalis production on a large scale.

The metabolism and detoxification effects of lead exposure on Aleurolyphus ovatus (Acari: Acaridae) via transcriptome analysis.

Aleurolyphus ovatus Troupeau is one of the most predominant species of the Acaridae family worldwide. Recent reports have demonstrated that the accumulation of lead in stored grains and dietary items exceeds the required standards. However, the molecular mechanism of heavy metal stress on mites has not been reported. To understand the mechanism underlying the heavy metal response of A. ovatus, comparative transcriptome analysis was performed in this study using an Illumina high throughput mRNA sequencing (RNA-seq) platform. A. ovatus was fed on artificial diets containing two different concentrations of lead, namely, a low concentration of 12.5 mg/kg (LAO) and a high concentration of 100 mg/kg (HAO), while the mites in the control (NAO) group were not exposed to lead. A total of 44,362 unigenes, with an average length of 1547 bp, were identified. Of these, 996 unigenes were successfully annotated in seven functional databases. The number of differentially expressed genes (DEGs) in A. ovatus under different lead concentrations was compared. In NAO versus LAO group, including 310 up-regulated and 1580 down-regulated DEGs. In NAO versus HAO group, including 3928 up-regulated and 1761 down-regulated DEGs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment indicated that detoxification enzyme genes were significantly expressed in pathways, such as cytochrome P450 foreign body metabolism, glutathione metabolism and drug metabolism-cytochrome pathway. The results of gene annotation and quantitative real-time PCR showed that high concentration of lead significantly stimulated the expression of metabolic detoxification enzyme genes such as glutathione S transferase (GST) and superoxide dismutase (SOD), while low concentration inhibited their expression. This study will provide a basis for the molecular mechanism of A. ovatus in response to heavy metal lead stimulation in stored grain.

Hormetic effects of neonicotinoid insecticides on Rhizoglyphus robini (Acari: Acaridae).

The stimulation of biological processes by sublethal doses of insecticides or other stressors is known as hormesis. Here, we have evaluated whether exposure to field-relevant or low concentrations of neonicotinoids induce changes in the reproductive capacity of the bulb mite Rhizoglyphus robini (Acari: Acaridae). Among the tested neonicotinoids imidacloprid, thiamethoxam, and dinotefuran, the highest hormetic effect on the reproduction of R. robini occurred 24 h after the 48 h exposure period to imidacloprid at concentrations of 70 and 140 mg a.i./L. Despite the stimulating effects of imidacloprid on mite reproduction, no significant differences were observed in the offspring (F1) for biological aspects including egg hatch rate, embryonic period and sex ratio, while an increase was found in the duration of development time from egg to adult. Evaluation of the detoxification enzyme activities of treated adults showed that the highest activity of carboxyl/cholinesterases, cytochrome P450s, and glutathione S-transferases was obtained when exposed to 70, 140 and 70 mg a.i./L imidacloprid, immediately after the exposure period, respectively. Also, an increase in the activity of the antioxidant enzyme catalase was observed compared to that of the control. After imidacloprid pretreatment (140 mg a.i./L), the tolerance of adult mites to diazinon was increased about two-fold. This study shows that exposure to imidacloprid can induce hormetic effects on R. robini and could severely complicate its control due to a higher reproduction, enhanced detoxification enzyme activities, and increased tolerance against other pesticides.

A sexually selected male weapon characterized by strong additive genetic variance and no evidence for sexually antagonistic polyphenic maintenance.

Sexual selection and sexual antagonism are important drivers of eco-evolutionary processes. The evolution of traits shaped by these processes depends on their genetic architecture, which remains poorly studied. Here, implementing a quantitative genetics approach using diallel crosses of the bulb mite, Rhizoglyphus robini, we investigated the genetic variance that underlies a sexually selected weapon that is dimorphic among males and female fecundity. Previous studies indicated that a negative genetic correlation between these two traits likely exists. We found male morph showed considerable additive genetic variance, which is unlikely to be explained solely by mutation-selection balance, indicating the likely presence of large-effect loci. However, a significant magnitude of inbreeding depression also indicates that morph expression is likely to be condition-dependent to some degree and that deleterious recessives can simultaneously contribute to morph expression. Female fecundity also showed a high degree of inbreeding depression, but the variance in female fecundity was mostly explained by epistatic effects, with very little contribution from additive effects. We found no significant genetic correlation, nor any evidence for dominance reversal, between male morph and female fecundity. The complex genetic architecture underlying male morph and female fecundity in this system has important implications for our understanding of the evolutionary interplay between purifying selection and sexually antagonistic selection.

Diet modulation of the microbiome of the pest storage mite Tyrophagus putrescentiae.

Storage mites colonize a wide spectrum of food commodities and adaptations to diets have been suggested as mechanisms enabling successful colonization. We characterized the response of seven unique Tyrophagus putrescentiae cultures (5K, 5L, 5N, 5P, 5Pi, 5S, and 5Tk) with different baseline microbiomes to different diets. The offered diets included a rearing diet, protein-enriched diet, oat flakes, and sunflower seeds. Microbiome characterization was performed using 16S ribosomal RNA (rRNA) gene amplicon sequencing and 16S rRNA gene quantitative PCR. The mite culture microbiomes were classified into four groups: (i) Sodalis-dominated (5Pi), (ii) Wolbachia-dominated (5N and 5P), (iii) Cardinium-dominated (5L and 5S), and (iv) asymbiontic (5K and 5Tk) mites dominated by Bacillus and Bartonella. Mite growth rates were most strongly affected by nutrients in the diet, while respiration and microbial community profiles were largely influenced by mite culture. While growth rate was not directly explained by microbiome composition, microbiomes strongly influenced mite fitness as measured by respiration. While diet significantly influenced microbial profiles in all cultures, the effect of diet differed in impact between cultures (5Pi > 5S > 5N > 5K > 5Tk > 5L > 5P). Furthermore, no new bacterial taxa were acquired by mites after dietary changes. Bacteria from the taxa Bacillus, Bartonella-like, Solitalea-like, Kocuria, and Sodalis-like contributed most strongly to differentiating mite-associated microbiomes.

Comparison of sensitization patterns to dust mite allergens between atopic dermatitis patients and dogs, and non-specific reactivity of canine IgE to the storage mite Tyrophagus putrescentiae.

House dust mite is a common cause of atopic dermatitis (AD) both in humans and dogs. Detection of serum IgE to allergens is commonly used to diagnose allergic diseases. However, false-positive reactions due to cross-reactivity and non-specific reactivity may lead to misdiagnosis. We compared human and canine IgE reactivities to mite component allergens. Canine IgE-reactive components of Dermatophagoides farinae and Tyrophagus putrescentiae were identified by tandem mass spectrometry. Recombinant proteins were produced and IgE reactivities to component allergens were assessed by ELISA and inhibition assays using sera from AD patients and dogs. Canine IgE-reactive proteins (Der f 1, Der f 11, Tyr p 4, Tyr p 8, Tyr p 11, Tyr p 28) were identified by proteome analysis. Most patients were sensitized to Der f 1 (93.3%) and Der f 2 (86.7%). Dogs showed high sensitization to Der f 2 (94.1%) and Der f 18 (84.6%). Both patients and dogs showed low IgE binding frequency to Tyr p 8, 43.3% and 4%, respectively. The ELISA inhibition study indicated that canine IgE reactivity to T. putrescentiae is mostly due to non-specific reaction and cross-reaction with D. farinae. Different IgE sensitization patterns were shown between allergic humans and dogs with AD, especially to Der f 18, for the first time in Korea. Furthermore, non-specific canine IgE reactivity to storage mite indicates the possibility of misdiagnoses. Standardizations focused on the major canine allergen content of extracts should be developed. This will allow precision diagnosis and individuated treatments for each patient and atopic dog.

Complete mitochondrial genomes of Thyreophagus entomophagus and Acarus siro (Sarcoptiformes: Astigmatina) provide insight into mitogenome features, evolution, and phylogeny among Acaroidea mites.

Mites from the Acaroidea (Sarcoptiformes: Astigmatina) are important pests of various stored products, posing potential threats to preserved foods. In addition, mites can cause allergic diseases. Complete mitochondrial genomes (mitogenomes) are valuable resources for different research fields, including comparative genomics, molecular evolutionary analysis, and phylogenetic inference. We sequenced and annotated the complete mitogenomes of Thyreophagus entomophagus and Acarus siro. A comparative analysis was made between mitogenomic sequences from 10 species representing nine genera within Acaroidea. The mitogenomes of T. entomophagus and A. siro contained 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), two ribosomal RNAs (rRNAs), and one control region. In Acaroidea species, mitogenomes have highly conserved gene size and order, and codon usage. Among Acaroidea mites, most PCGs were found to be under purifying selection, implying that most PCGs might have evolved slowly. Our findings showed that nad4 evolved most rapidly, whereas cox1 and cox3 evolved most slowly. The evolutionary rates of Acaroidea vary considerably across families. In addition, selection analyses were also performed in 23 astigmatid mite species, and the evolutionary rate of the same genes in different superfamilies exhibited large differences. Phylogenetic results are mostly consistent with those identified by previous phylogenetic studies on astigmatid mites. The monophyly of Acaroidea was rejected, and the Suidasiidae and Lardoglyphidae appeared to deviate from the Acaroidea branch. Our research proposed a review of the current Acaroidea classification system.

Pesticide residue exposure provides different responses of the microbiomes of distinct cultures of the stored product pest mite Acarus siro.

BACKGROUND: The contribution of the microbiome to pesticide breakdown in agricultural pests remains unclear. We analyzed the effect of pirimiphos-methyl (PM) on four geographically different cultures of the stored product pest mite Acarus siro (6 L, 6Tu, 6Tk and 6Z) under laboratory experiments. The effect of PM on mite mortality in the impregnated filter paper test was compared. RESULTS: The mite sensitivity to PM decreased in the order of 6 L, 6Tu, 6Tk, and 6Z. Then, the mites were cultured on PM residues (0.0125 and 1.25 µg·g-1), and population growth was compared to the control after 21 days of exposure. The comparison showed two situations: (i) increasing population growth for the most sensitive cultures (6 L and 6Tu), and (ii) no effect on mite population growth for tolerant cultures (6Z and 6Tk). The microbiome of mites was analyzed by quantification of 16S DNA copies based on quantitative polymerase chain reaction (qPCR) and by barcode sequencing of the V4 fragment of 16S DNA on samples of 30 individuals from the control and PM residues. The microbiome comprised primarily Solitalea-like organisms in all cultures, except for 6Z, followed by Bacillus, Staphylococcus, and Lactobacillus. The microbiomes of mite cultures did not change with increasing population density. The microbiome of cultures without any differences in population density showed differences in the microbiome composition. A Sodalis-like symbiont replaced Solitalea in the 1.25 µg·g-1 PM in the 6Tk culture. Sodalis and Bacillus prevailed in the microbiomes of PM-treated mites of 6Z culture, while Solitalea was almost absent. CONCLUSION: The results showed that the microbiome of A. siro differs in composition and in response to PM residues in the diet. The results indicate that Sodalis-like symbionts can help recover mites from pesticide-induced stress.

Activation of mycelial defense mechanisms in the oyster mushroom Pleurotus ostreatus induced by Tyrophagus putrescentiae.

Fungal chemicals are vital in processes recognizing damage- and microbe-associated molecules (DAMPs/MAMPs) that trigger defense responses in fungi. Pleurotus ostreatus is a widely cultivated edible fungus that is prone to attack from fungivorous insects and mites. Yet P. ostreatus has evolved an elegant defense system against fungivore attacks. In this study, we investigated how the oyster mushroom responds to the fungivory and mechanical wounding by conducting transcriptome, proteome, and secondary metabolic analyses. The profiling analysis revealed a total of 11,495 transcripts and 866 proteins, 4416 differentially expressed genes (DEGs), and 62 differentially expressed proteins (DEPs) were identified in response to the mite Tyrophagus putrescentiae feeding and mechanical wounding. In comparing the responses induced by mechanical wounding, some genes, proteins, and metabolites were uniquely induced or repressed by the mite. At the transcript level, nine pathways were activated by the mite feeding, including those of "MAPK signaling pathway-yeast", "Phenylalanine metabolism", and "Biotin metabolism", among others, while both enrichment of "Ribosome", "Ribosome biogenesis in eukaryotes", and "Regulation of Mitophagy in Yeast" demonstrated the common effects upon fungal secretory protein synthesis and processing induced by fungivory and mechanical wounding. Fungivory also stimulated the synthesis of C8-aryl compounds and sesquiterpenes (especially1-octen-3-ol and α-/ß-bisabolene), and these compounds repellent to T. putrescentiae. Both jasmonic acid (JA) and jasmonic acid methyl ester (MeJA) were specifically regulated by mite feeding and mechanical wounding. The terpene synthase gene transcription was significantly increased induced by the exogenous addition of MeJA, resulting in defensive sesquiterpene production against the mite. These findings are the first to demonstrate that the reactive oxygen species (ROS)/MAPK signaling pathway, JA regulation, specific gene expression, and protein synthesis, and anti-mite substance metabolism are all involved in coordinated inducible chemical-based defense responses in P. ostreatus, which could be especially effective the mite T. putrescentiae.

Do 'cheese factory-specific' mites (Acari: Astigmata) exist in the cheese-ripening cabinet?

To determine whether the mites used in the ripening process of traditional cheeses are genetically unique to cheese factories, we investigated mites from three types of traditional cheeses, that use mites in the ripening process: 'Würchwitzer Milbenkäse' from Germany and 'Mimolette' and 'Artisou' from France. In addition, traditional ripened cheeses were purchased from cheese specialty stores in France (Mimolette) and Japan ('Laguiole' from France) as well as stores in temporary markets in France ('Salers' and 'Cantal vieux') and the mites obtained from those cheeses were analyzed in this study. Partial sequences of the 28S rRNA gene (28S) were determined and used to reconstruct a phylogenetic tree. Tyrolichus casei, the dominant cheese mite species from the ripening cabinets of three traditional cheese producers and two cheese specialty stores in France and Japan, had identical partial 28S sequences. All specimens from Cantal vieux from a store in the temporary market in France had an identical sequence with Acarus siro and Acarus immobilis in the determined region of the 28S sequences. Mite individuals from Salers from a store in the temporary markets in France shared the same haplotype as Acotyledon paradoxa. For the T. casei individuals from five different localities (19 individuals in total), the nuclear loci were obtained using MIG-seq. More than several thousand genomic regions are amplified simultaneously by multiplex PCR, and targeting regions surrounded by inter-simple sequence repeats (ISSRs) in the genome were sequenced using the MiSeq system (Illumina). SNPs extracted from this genome-wide analysis showed that no genetic structure existed in the populations from any region. Among the five samples from the three regions, which were more than 500 km apart and from completely different environments, the mites had no geographic bias, but all mite individuals were genetically nearly identical. Thus, we found no evidence to support the existence of 'cheese factory-specific' T. casei mites, at least in terms of genetic analysis.

Evaluation of the entomopathogenic fungus Metarhizium brunneum and the predatory mite Stratiolaelaps scimitus against Rhizoglyphus robini under laboratory conditions.

Rhizoglyphus robini Claparède (Acari: Acaridae) is a pest of bulbs, corms and tubers of several economically important crops. The biological control of R. robini has yet to be fully explored as an alternative to chemical pesticides. Entomopathogenic fungi in the genera Metarhizium (Hypocreales: Clavicipitaceae) are used for the biological control of several agricultural pests. The soil-dwelling predatory mite, Stratiolaelaps scimitus (Womersley) (Acari: Acaridae) is also frequently used alone or in combination with other biological control agents. There are few reports on the use of M. brunneum or S. scimutus against R. robini. The objectives of this research were to investigate the in vitro effect of different predatory mite ratios of S. scimitus on R. robini mortality and the combined use of a M. brunneum-based granule with S. scimitus as potential strategies to manage this pest. Mortality of R. robini in Petri dishes containing predators was significantly higher than without predators. When soil-filled containers containing R. robini were treated with both M. brunneum granules and S. scimitus, the lower densities of the bulb mite were obtained with the highest ratio of predator/prey mites. The number of bulb mites in the containers treated with only M. brunneum was significantly lower than the untreated control. These results demonstrate the potential for releasing of S. scimitus alone and in combination with M. brunneum granules to manage R. robini.

Effects of temperature on the adults and progeny of the predaceous mite Lasioseius japonicus (Acari: Blattisociidae) fed on the cereal mite Tyrophagus putrescentiae (Acari: Acaridae).

The predatory mite Lasioseius japonicus Ehara is a newly recorded species in China that has been shown to have great potential as a biological control agent. The species is a soil-dwelling mite that is known to prey on various pests including economically important mites, fungus gnats and other terricolous arthropods. Considering that temperature is one of the most important factors affecting the population dynamics of arthropods, the development, survival and reproduction of L. japonicus were evaluated under indoor conditions at seven temperatures: 19, 22, 25, 28, 31, 34 and 37 °C, at 75% relative humidity and L0:D24 h photoperiod. The mites were fed on the cereal mite Tyrophagus putrescentiae (Schrank) and the data were analyzed using the two-sex life table. The results demonstrated that L. japonicus could complete their development and reproduce at temperatures between 19 and 34 °C, but were unsuccessful at 37 °C. Increasing temperature shortened the development time of the pre-adult stage and the average generation time (T). The life table parameters indicated that at temperatures from 22 to 31 °C the development rate and reproduction of L. japonicus were highest: at 22, 25, 28 and 31 °C the net reproduction rate (R0) was 55.5, 61.6, 61.2 and 59.0, respectively, and the average fecundity rate (F) was 81.7, 88.0, 102.0 and 86.8, respectively. The maximum values of intrinsic population growth rate (r) (0.341) and finite rate of increase (λ) (1.407) occurred at 31 °C.

Storage Mite Precision Allergy Molecular Diagnosis in the Moderate-to-Severe T2-High Asthma Phenotype.

Storage mites (SM) may induce allergic respiratory symptoms in sensitized individuals, in both rural and urban settings. The relationship among specific IgE reactions to determined groups of SM allergens in the coincident asthma pheno-endotypes has not yet been investigated. We aimed to study a Precision Allergy Molecular Diagnosis (PAMD@) model to depict the SM molecular profile in individuals presenting with Type-2 inflammation, in two different (moderate and severe) asthma phenotypes. A customized PAMD@ panel, including SM allergens and their concurrent protein allergenic characterization was investigated. Mite group 2 allergens were most frequently recognized, including Lep d 2 (83.45%), followed by Gly d 2 (69.17%) and Tyr p 2 (47,37%), in 133/164 asthmatic subjects. Blo t 5 and Blo t 21 exhibited significant higher titres in both asthma groups. Although relevant mite group 2 allergens cross-reactivity is suggested, individualized sensitization patterns were relevantly identified. The present PAMD@ panel confirmed the dominance of mite group 2 allergens in moderate-to-severe T2 asthmatics. A broadly heterogeneous molecular repertoire of SM allergens was found in all subjects, regardless of their asthma severity. Blomia tropicalis deserves special attention in certain territories, as diagnostic and/or therapeutic approaches merely based on Pyroglyphidae mites may be insufficient.

Nitric Oxide Fumigation for Control of Ham Mite, Tyrophagus putrescentiae (Sarcoptiformes: Acaridae).

The ham mite, Tyrophagus putrescentiae (Schrank) (Sarcoptiformes: Acaridae), is a common pest infesting several stored products, particularly the aged hams. In this study, we reported the efficacy of nitric oxide (NO) fumigation, a recently discovered fumigation treatment under the ultra-low oxygen environment, at various concentrations and time under the laboratory conditions at 25°C against different mite stages on both dietary media and ham meat. Our results showed that NO fumigation was effective against all mite stages and 100% control was achieved. Generally, the egg was the most tolerant stage and required 48-, 24-, 16-, and 8-h treatments to achieve 100% mortality at 0.5, 1, 1.5, and 2% NO concentration on dietary media, respectively. Tyrophagus putrescentiae mobile immatures and adult stages were less tolerant, and 100% mortality was achieved after 16-, 8-, 8-, and 4-h treatment at 0.5, 1, 1.5, and 2% NO, respectively. The median lethal concentration (LC50) of NO on egg was 0.86, 0.68, and 0.32% for 8-, 16-, and 24-h treatments. In addition, a confirmatory test was conducted on ham meat at 0.5 and 1.0% of NO and similar efficacy was found. Complete control of egg was achieved after 48- and 24-h treatment at 0.5 and 1.0% of NO, respectively, and larvae and adult mites were 100% controlled after 16 and 8 h at 0.5 and 1.0% of NO, respectively. Our results demonstrated that NO fumigation was effective against T. putrescentiae and can be a potential alternative treatment to methyl bromide for cured-ham pest control.

Effects of Local Nasal Immunotherapy with FIP-fve Peptide and Denatured Tyrophagus putrescentiae for Storage Mite-Induced Airway Inflammation.

Allergic diseases are affecting public health and have increased over the last decade. Sensitization to mite allergens is a considerable trigger for allergy development. Storage mite-Tyrophagus putrescentiae shows great significance of allergenic potential and clinical relevance. The fungal immunomodulatory peptide FIP-fve has been reported to possess immunomodulatory activity. We aimed to determine whether T. putrescentiae-induced sensitization and airway inflammation in mice could be downregulated by FIP-fve in conjunction with denatured T. putrescentiae (FIP-fve and DN-Tp). Immune responses and physiologic variations in immunoglobulins, leukocyte subpopulations, cytokine productions, pulmonary function, lung pathology, cytokines in CD4+ and Treg cells were evaluated after local nasal immunotherapy (LNIT). After the LNIT with FIP-fve and DN-Tp, levels of specific IgE, IgG1, and IgG2a in the sera and IgA in the bronchoalveolar lavage fluid (BALF) were significantly reduced. Infiltrations of inflammatory leukocytes (eosinophils, neutrophils, and lymphocytes) in the airway decreased significantly. Production of proinflammatory cytokines (IL-5, IL-13, IL-17F and IL-23) and chemokine (IL-8) were significantly reduced, and Th1-cytokine (IL-12) increased in the airway BALF after LNIT. Pulmonary functions of Penh values were significantly decreased after the methacholine challenge, which resulted in a reduction of airway hypersensitivity after LNIT. Bronchus pathology showed a reduction of inflammatory cell infiltration and epithelium damage after LNIT. The IL-4+/CD4+ T cells could be downregulated and the IFN-γ+/CD4+ T cells upregulated. The Treg-related immunity of IL-10 and Foxp3 expressions in CD4+CD25+ cells were both upregulated after LNIT. In conclusion, LNIT with FIP-fve and DN-Tp had an anti-inflammatory effect on mite-induced airway inflammations and possesses potential as an immunomodulatory therapy agent for allergic airway diseases.