Dolichovespula Maculata Research Articles

Structure of recombinant Ves v 2 at 2.0 Å resolution: structural analysis of an allergenic hyaluronidase from wasp venom

Wasp venom from Vespula vulgaris contains three major allergens: Ves v 1, Ves v 2 and Ves v 5. Here, the cloning, expression, biochemical characterization and crystal structure determination of the hyaluronidase Ves v 2 from family 56 of the glycoside hydrolases are reported. The allergen was expressed in Escherichia coli as an insoluble protein and refolded and purified to obtain full enzymatic activity. Three N-glycosylation sites at Asn79, Asn99 and Asn127 were identified in Ves v 2 from a natural source by enzymatic digestions combined with MALDI-TOF mass spectrometry. The crystal structure of recombinant Ves v 2 was determined at 2.0 A resolution and reveals a central (beta/alpha)(7) core that is further stabilized by two disulfide bonds (Cys19-Cys308 and Cys185-Cys197). Based on sequence alignments and structural comparison with the honeybee allergen Api m 2, it is proposed that a conserved cavity near the active site is involved in binding of the substrate. Surface epitopes and putative glycosylation sites have been compared with those of two other major group 2 allergens from Apis mellifera (honeybee) and Dolichovespula maculata (white-faced hornet). The analysis suggests that the harboured allergic IgE-mediated cross-reactivity between Ves v 2 and the allergen from D. maculata is much higher than that between Ves v 2 and the allergen from A. mellifera.

The N‐glycans of yellow jacket venom hyaluronidases and the protein sequence of its major isoform in Vespula vulgaris

Hyaluronidase (E.C. 3.2.1.35), one of the three major allergens of yellow jacket venom, is a glycoprotein of 45 kDa that is largely responsible for the cross-reactivity of wasp and bee venoms with sera of allergic patients. The asparagine-linked carbohydrate often appears to constitute the common IgE-binding determinant. Using a combination of MALDI MS and HPLC of 2-aminopyridine-labelled glycans, we found core-difucosylated paucimannosidic glycans to be the major species in the 43-45 kDa band of Vespula vulgaris and also in the corresponding bands of venoms from five other wasp species (V. germanica, V. maculifrons, V. pensylvanica, V. flavopilosa and V. squamosa). Concomitant peptide mapping of the V. vulgaris 43 kDa band identified the known hyaluronidase, Ves v 2 (SwissProt P49370), but only as a minor component. De novo sequencing by tandem MS revealed the predominating peptides to resemble a different, yet homologous, sequence. cDNA cloning retrieved a sequence with 58 and 59% homology to the previously known isoform and to the Dolichovespula maculata and Polistes annularis hyaluronidases. Close homologues of this new, putative hyaluronidase b (Ves v 2b) were also the major isoform in the other wasp venoms.

Insect Stings

Insect Stings

Comparison of Three Liquid Lures for Trapping Social Wasps (Hymenoptera: Vespidae)

Two citrus-based sodas and a known wasp attractant were compared in a field trial to assess their attractiveness to local nuisance wasp species. The wasps captured included Vespula germanica (F.), Vespula maculifrons (Buysson), Vespula vulgaris (L.), Vespula flavopilosa Jacobson, Vespula squamosa (Drury), Dolichovespula maculata (L.), Polistes fuscatus (L.), Polistes metricus Say, and Polistes dominulus (Christ). Wasps in the genus Vespula were present in significantly higher numbers in traps than Dolichovespula and Polistes. Both citrus soda products were superior to the isobutanol-acetic acid mixture as attractants for almost all of the wasp species.

A case of leukocytoclastic vasculitis following insect immunotherapy

Rationale To describe a case of leukocytoclastic vasculitis resulting from mixed vespid and wasp immunotherapy. Methods A 68-year-old man with no prior allergies to vespid or wasp stings was stung multiple times and immediately developed a severe anaphylactic reaction manifesting as rapid loss of consciousness that required multiple injections of epinephrine. Prick skin testing was performed using standard procedures and he was treated with a mixed vespid and wasp rush desensitization protocol. Two days after receiving injection of his first maintenance dose (100 μg) he developed a palpable purpuric rash. The patient was otherwise asymptomatic and was not taking medication. A biopsy of his rash was performed. Immunotherapy was discontinued, he was treated with antihistamine and his rash resolved without sequelae. Results Prick skin testing revealed a 10 mm wheal with extracts of yellow jacket, yellow hornet and white-faced hornet. Histamine and saline measured 5 mm and 0 mm respectively. Punch skin biopsy revealed a perivascular lymphocytic infiltrate within the superficial dermis consistent with leukocytoclastic vasculitis. Connective tissue disease work-up and hepatitis screen was normal. Conclusions The chronology of this patient's leukocytoclastic vasculitis was probably due to venom immunotherapy. There is one previous case report describing a similar reaction following rush desensitization following venom immunotherapy. Although immunotherapy in patients with known vasculitis is a relative contra-indication, it may be prudent to warn patients that leukocytoclastic vasculitis is a potential risk of immunotherapy. Immunotherapy should be discontinued in patients with this type of reaction.

Food Volatiles as Attractants for Yellowjackets (Hymenoptera: Vespidae)

Abstract Assays with a captive Vespula germanica (F.) colony indicated that foragers were more strongly attracted to pear aged 24 h than to 0- or 48-h-aged pear. Sixteen chemicals found in 24-h pear and other foods were tested for their attractiveness to social wasps in a series of four trapping trials in rural and urban settings in Wisconsin. Workers of V. germanica, V. maculifrons, Dolichovespula maculata (L.), and Polistes fuscatus (F.) were most strongly attracted to isobutanol with 0.5% acetic acid added to the drowning solution, confirming previous work. We report for the first time that males of V. maculifrons were trapped in significant numbers by the isobutanol + acetic acid combination. None of the tested compounds found in ripe pear was shown to be especially attractive to V. germanica or V. maculifrons workers or males. However, 2-methyl butanol, a compound similar in structure to isobutanol, was found to attract V. germanica and V. maculifrons workers as well as V. maculifrons males. Furtherm...

STINGING INSECT VACCINES

Immunotherapy for prevention of allergic reactions to insect stings has a long history checkered by the use of whole body extracts for over 50 years, 24 the eventual development (25 years ago) of the first standardized extracts with specific Hymenoptera venom protein allergens, 38 and the refinement of arguably the most effective form of treatment available to allergists and their patients. 28 The appropriate clinical application of this remarkable treatment requires an understanding of the clinical patterns of reaction, the natural history of the disease, and the human immune response to insect venoms. The simple fact that whole body extracts were certified as being effective, even though they are no more effective than placebo, illustrates the importance of recognizing the distinction between natural history and therapeutic effect. Although the research of the past 20 years has revealed many of the markers and patterns of reactions that enable the statistical prediction of risk, there remains a fundamental deficiency in understanding that limits the ability to predict with precision which individuals will have a severe reaction to a sting. The current standard of practice in North America rests primarily on statistical observations that provide the framework for patient selection and for the methods of administration of venom immunotherapy. The risk of anaphylaxis occurs primarily with stinging insects of the order Hymenoptera. Insect bites by numerous species can cause local inflammation, swelling (including IgE-mediated reactions), and toxic systemic reactions to envenomation, but the occurrence of anaphylaxis from biting insects is rare. There are three families of Hymenoptera with clinical importance: bees (e.g., honeybees, bumblebees), vespids (e.g., yellow jackets, hornets, wasps), and fire ants (e.g., genus Soienopsis ). Exposure to these insects is affected by environmental and ecological changes. The predominant species of fire ants was imported inadvertently through Mobile, Alabama in the early part of the twentieth century and has rapidly become an increasing public health hazard in the southeast and southern United States. 4 The Africanized honeybee (killer bee) is an aggressive hybrid resulting from an ill-advised experiment to enhance honey production. The danger from the Africanized honeybee stems from the numbers of stings because of swarm-and-attack behavior rather than any greater allergenicity or toxicity of their venom, which is in fact similar to that of other honeybees. The allergens in honeybee venom are immunochemically distinct from those of the vespid venoms (see article by Weber elsewhere in this issue). 41 The vespid venoms cross-react and contain essentially the same allergens. 36 The yellow jacket and hornet venoms are related so closely that 95% of vespid-allergic patients have positive skin tests to all three of the common vespid skin test preparations: yellow jacket, yellow hornet, and white-faced hornet. Polistes wasps are more distantly related to the other vespids, and only 50% of yellow-jacket–allergic patients have cross-reactive positive tests to wasp venom. Fire ant venoms are unique in that they contain minimal protein in a suspension of alkaloid toxins. The alkaloid component is the cause of the painful, sterile, and pustule characteristic of fire ant stings but does not cause allergic reactions. The allergenic proteins of fire ants are unique except for one that cross-reacts slightly with a vespid allergen. 37

Social Wasps (Hymenoptera: Vespidae) Trapped with Acetic Acid and Isobutanol

The combination of acetic acid and isobutanol is attractive to different species of Vespidae in different areas of the United States. In Washington, the blend was attractive to workers and queens of Vespula pensylvanica (Saussure), Vespula germanica (F.), and workers of Dolichovespula maculata (L.). In Maryland, these chemicals were attractive to worker Vespula maculifrons (Buysson), worker V. germanica, worker Vespula squamosa (Drury), worker D. maculata, worker Vespa crabro L., and female Polistes dominulus F. In Oklahoma, the blend was attractive to worker V. maculifrons, worker V. squamosa, female Polistes fuscatus (F.), and Polistes annularis (L.). Several species were weakly attracted to acetic acid alone; V. maculifrons and D. maculata in Maryland, and V. squamosa, V. maculifrons, P. fuscatus, P. perplexus, and P. annularis in Oklahoma. Queens of V. germanica in Washington, workers of V. maculifrons in Maryland, as well as workers of V. squamosa and V. maculifrons in Oklahoma were weakly attracted to isobutanol alone.

Vespid Venom Analysis with Phylogenetic Inferences

Abstract The protein pattern analysis of the venoms of different Vespoidea species ( Dolichovespula, Vespa , and Polistes ) reveal strong similarities between both social wasp species of the genus Dolichovespula (arenaria and maculata ) and between the other social wasp species of Vespa ( mandarinia and tropica ). Species of Polistinae ( Polistes arizonensis, aurifer, canadensis and rothneyi grahami ) appear to have evolved early, but there are not enough characters to establish monophyly of subfamily Polistinae.

Hornet venom allergen antigen 5, Dol m 5: Its T-cell epitopes in mice and its antigenic cross-reactivity with a mammalian testis protein

Background: A major venom allergen of white-faced hornet (Dolichovespula maculata) is antigen 5, Dol m 5. It is a 204-residue protein having 23% to 35% sequence identity with several proteins from diverse sources. The biologic function of antigen 5 and its sequence-related proteins is not known. Objective:This study was done to delineate the T-cell epitopes of Dol m 5 and to test their cross-reactivity with a sequence-related mouse testis protein, tpx. Methods:T-cell epitope mapping and cross-reactivity were studied with 15- or 20-residue peptides by their stimulation of spleen cells from mice immunized with recombinant Dol m 5 or tpx fragments. Results:Three of 20 peptides studied were found to represent major T-cell epitopes of Dol m 5, being recognized by five or all of six mouse strains tested. One major epitope peptide, residue 176-195, showed cross-reactivity in BALB/c mice with the homologous antigen 5s from yellow jackets and wasps, as well as with mouse tpx. The cross-reactivity of Dol m 5 and mouse tpx is not reciprocal because spleen cells from tpx-immunized mice were stimulated by the hornet peptide, but cells from Dol m 5-immunized mice were not stimulated by the corresponding tpx peptides. Conclusion:Cross-reactivity of vespid antigen 5 and mouse tpx may be of importance in insect allergy because human and mouse testis proteins are highly homologous. (J Allergy Clin Immunol 1997;99:630-9.)

Sperm Use Dynamics of the Baldfaced Hornet (Hymenoptera: Vespidae)

The sperm content of the spermatheca of Dolichovespula maculata (L.) queens was examined before nest initiation and during colony development in 1987 and 1989. Several nonlinear regression models were tested in an effort to characterize sperm use as a function of colony size. Based on counts of cells per nest, spermatheca sperm counts were fit well by an exponentially decreasing mean and overdispersed negative binomial variance that depend on initial spermatheca sperm count and colony size at time of collection. The probability of successful nest founding appears to be dependent on initial sperm count, which varies with insemination success, either through mating frequency or the number of sperm transferred per mating. Results suggest that mean sperm count of queens in natural populations is influenced by the differential success in nest founding, as well as by physiological mechanisms governing sperm release during egg laying. The potential effects of mating success and sperm use on colony development are discussed.

Yellow jacket venom allergens, hyaluronidase and phospholipase: Sequence similarity and antigenic cross-reactivity with their hornet and wasp homologs and possible implications for clinical allergy

Three known allergens of yellow jacket (Vespula vulgaris) venom are antigen 5, hyaluronidase, and phospholipase. Yellow jacket antigen 5 has been previously cloned and expressed in bacteria; it contains 204 amino acid residues, and it has 69% and 60% sequence identities with the homologous proteins of white-faced hornet (Dolichovespula maculata) and wasp (Polistes annularis), respectively. These studies are now extended to yellow jacket hyaluronidase and phospholipase; they contain 331 and 300 amino acid residues, respectively, and they show 92% and 67% sequence identity with their homologs of white-faced hornet. Tests with the natural and the recombinant vespid allergens in mice indicate partial antigenic cross-reactivity of their homologous proteins at both B- and T-cell levels. There is greater cross-reactivity among hornet and yellow jacket allergens than that among hornet or yellow jacket and wasp allergens. The order of cross-reaction of the three vespid allergens is hyaluronidase > antigen 5 > phospholipase. The continuous (linear) B-cell epitopes of vespid allergens show greater cross-reactivity than their discontinuous epitopes do. The discontinuous B-cell epitopes are immunodominant for all vespid allergens. The low degree of cross-reactivity of the immunodominant discontinuous B-cell epitopes of vespid allergens should be taken into consideration in selection of venoms for immunotherapy of patients with sensitivity to multiple vespids. (J A LLERGY C LIN I MMUNOL 1996;98:588-600.)

Sequence Identity and Antigenic Cross-reactivity of White Face Hornet Venom Allergen, Also a Hyaluronidase, with Other Proteins

White face hornet (Dolichovespula maculata) venom has three known protein allergens which induce IgE response in susceptible people. They are antigen 5, phospholipase A1, and hyaluronidase, also known as Dol m 5, 1, and 2, respectively. We have cloned Dol m 2, a protein of 331 residues. When expressed in bacteria, a mixture of recombinant Dol m 2 and its fragments was obtained. The fragments were apparently generated by proteolysis of a Met-Met bond at residue 122, as they were not observed for a Dol m 2 mutant with a Leu-Met bond. Dol m 2 has 56% sequence identity with the honey bee venom allergen hyaluronidase and 27% identity with PH-20, a human sperm protein with hyaluronidase activity. A common feature of hornet venom allergens is their sequence identity with other proteins in our environment. We showed previously the sequence identity of Dol m 5 with a plant protein and a mammalian testis protein and of Dol m 1 with mammalian lipases. In BALB/c mice, Dol m 2 and bee hyaluronidase showed cross-reactivity at both antibody and T cell levels. These findings are relevant to some patients' multiple sensitivity to hornet and bee stings.

Role of Nest‐paper Hydrocarbons in Nestmate Recognition of Dolichovespula maculata (L.) Workers (Hymenoptera: Vespidae)

AbstractThe role of nest‐paper hydrocarbons in nestmate recognition was examined in the social wasp Dolichovespula maculata. Pupae were excised from nine colonies of D. maculata and placed in separate gel capsules in the laboratory. When workers emerged, they were isolated in the absence of other wasps in one of four conditions: 1. With an untreated fragment of their natal nest; 2. With a fragment of their nest that had been extracted with hexane to remove surface hydrocarbons; 3. With a fragment of their nest that had been extracted with hexane, and had then had the extract containing the surface hydrocarbons reapplied; or 4. In the absence of any nest fragment. After 4 d, the newly emerged workers were tested for nestmate recognition with an experienced nestmate and an experienced non‐nestmate in blind triplet tests. Prior exposure to nest‐paper hydrocarbons had no significant effect upon the ability of newly emerged or experienced wasps to recognize their nestmates. Moreover, nestmate recognition did not occur in any treatment group.

Insect Life: Our Stinging Friends? The Ambivalent Yellowjackets

My earliest memories of yellowjackets are of an aerial nest of the baldfaced hornet in a dense patch of brush and small trees. A friend and I were running through the forest when the nest suddenly appeared right in front of my face. Contact was made a second later when the nest was pushed up and out of the way by my head, only to spring back on my friend who was right behind me. Punishment was swift and severe as the wasps vigorously attacked. My punishment? After disturbing the wasps, I escaped without a single sting. However, I did feci bad for my friend who was stung so severely that his eyes nearly swelled shut.

Egg Weights, Energy Reserves, and Internal Nest Temperatures in Embryo Nests of Dolichovespula maculata (Hymenoptera: Vespidae)

Eggs of the baldfaced hornet, Dolichovespula maculata (L.), were collected from embryo (spring) nests and summer nests to quantify the energetic contributions provided by the queen. Egg weights were highest in the spring and decreased with progressive nest development. Mean dry weight of eggs in embryo nests was 266.4µg; August nests had a mean dry egg weight of 179.6µg. Nutrient reserves of eggs in embryo nests, in order of importance, were lipid (22%), glucose (9.5%), and glycogen (5%). A 10-d egg incubation experiment snowed a mean loss of 83µg in egg dry weight from an initial weight of 282µg. Temperature recordings from an embryo nest indicated that D. maculata queens can increase the temperature within an embryo nest as much as 4°C above ambient. The energetic contributions that a queen provides to the eggs are discussed with respect to environmental influences on development.

Allergens in Hymenoptera Venom

The 2 major allergenic proteins in vespid venoms are antigen 5s and phospholipases (PLs). Vespid PLs have a molecular weight of about 34,000 and have been previously shown to have an A1B specificity, unlike the A2 specificity of bee PLs. The complete amino acid sequences of the venom PL from the yellow jacket, Vespula maculifrons, and the more acidic isoenzyme from the white faced hornet, Dolichovespula maculata, have been determined by sequencing overlapping peptides isolated from enzyme and chemical digests of the proteins. Ves m 1 is composed of 300 amino acids, with variants found at 3 positions. Dol m 1.02 is composed of 303 amino acids with variants at 2 positions. Comparison with the sequence of Dol m 1.01 determined by cDNA sequencing gave 66.7% identity with Dol m 1.01 with almost all variation in the first 131 positions. Ves m 1 showed 69% identity with Dol m 1.01 and 38.7% with Dol m 1.02. Comparison of the PL sequences with the Protein Identification Resource data base showed many similarities with the lipase family, but very little relationship to known PLs. The amount of structural similarity between Dol m 1 and Ves m 1 is similar to that found among antigen 5 molecules of different genera, and is sufficient to account for antigenic cross-reactivity. There appear to be a number of highly conserved regions of the PL molecules, especially in the C-terminal 168 residues. These regions may from common epitopes found in several species and genera of vespids. Antibodies against these common epitopes will not be able to distinguish among PLs from various vespids.(ABSTRACT TRUNCATED AT 250 WORDS)

Sequence similarity of a hornet (D. maculata) venom allergen phospholipase A 1 with mammalian lipases

We have determined the sequence of a venom allergen phospholipase A 1 from white-faced hornet (Dolichovespula maculata) by cDNA and protein sequencings. This protein of 300 amino acid residues ( Dol m I) has no sequence similarity with other known phospholipases. But it has sequence similarity with mammalian lipases; about 40% identity in overlaps of 123 residues. Tests suggest that hornet phospholipase has weak lipase activity. Hornet venom has 3 major allergens, and another hornet allergen antigen 5 ( Dot m V) was previously found to have sequence similarity with a mammalian testis protein and a plant leaf protein.

Expression of hornet genes encoding venom allergen antigen 5 in insects.

Antigen 5, also known as Dol m V, is a major allergen found in the venom of the baldfaced hornet, Dolichovespula maculata. We have inserted the f10 and f17 cDNAs, which encode hornet antigen 5 (HA5) forms 2 (Dol m; VB) and 3 (Dol m VA), respectively, into the genome of the baculovirus, AcMNPV, to produce the recombinant baculovirus gene expression vectors, vEV-HA5f10 and vEV-HA5f17. Insect cells infected with either vEV-HA5f10 or vEV-HA5f17 produce and secrete a novel protein with an electrophoretic mobility which is similar if not identical to authentic mature Dol m V. The gene products also react specifically with a polyclonal antiserum raised to Dol m VB as expected. Dol m V gene products were not acutely toxic when injected into insect larvae. However, infection of fifth instar larvae with vEV-HA5f17 resulted in premature melanization of the larvae and lower weight gain than infection with control virus. Thus, the Dol m V gene product has a subtle, possibly cytotoxic or biochemical effect on insects. The expression systems may prove useful in further structural and functional characterization of these proteins.

Seasonal Comparison of Weight, Energy Reserve, and Nitrogen Changes in Queens of the Baldfaced Hornet (Hymenoptera: Vespidae)

Queens of Dolichovespula maculata (L.) were collected before the hibernation period in the fall, before and shortly after nest initiation in the spring, and after colonies had produced more than two worker broods. Fresh and dry weights were determined for all queens, and a seasonal comparison of the energy reserves of lipids, sugar, and glycogen was performed on the thoracic and abdominal tagmata. Total nitrogen also was quantified to estimate protein changes by season. The results show that during hibernation, 70.1% (101.8 mg) of the lipid reserves, 79.4% (26.0 mg) of the sugar reserves, and 84.8% (6.9 mg) of the glycogen reserves were used. Furthermore, lipid use accounted for 35% of the dry-weight loss, sugar use 12%, and glycogen use 6%. Total thoracic nitrogen remained constant throughout the year, whereas abdominal nitrogen was the same in the fall and spring queens but increased in the summer queens. The results of this study suggest that most queens that survive the winter and successfully initiate nests have similar quantities of energy reserves. The implications of solitary foraging behavior are discussed.