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Allergens in Hymenoptera venoms. IV. Comparison of venom and venom sac extracts.

Honeybee venom sac extract is compared with pure venom. All five known allergens of venom are present in venom sac extract. Enzyme analyses indicate that the sac extracts contain 11% to 16% venom. At least 10 additional components, several of which are proteins, are present in venom sac extract. Radioallergosorbent test (RAST) studies of yellow jacket venom and venom sac extract yielded a correlation of r = 0.94, with only some weakly reactive sera positive to only one preparation. A few sera were substantially more reactive with venom sac extract. Venom sac extracts appear to be suitable for in vitro diagnostic use, but the extraneous proteins and peptides may make them less suitable than pure venoms for use in immunotherapy.

Acid Phosphatase

IgE antibodies to bee venom, phospholipase A, melittin and wasp venom.

Specific IgE antibodies against bee venom, phospholipase A, melittin and wasp venom have been examined in fifty patients with an unusually severe reaction after bee or wasp sting. Two thirds of the bee venom-sensitive patients also have detectable IgE antibodies to wasp venom. More than 50% of the wasp venom-sensitive patients are also allergic to bee venom. Phospholipase A and melittin IgE antibodies were found, respectively, in two thirds and one third of the bee venom-sensitive cases. Specific IgE antibody determinations by the Radioallergosorbent test play an essential role in the diagnostic work. After a reaction to hymenoptera stings both bee and wasp venom tests are necessary due to the high incidence of a false or incomplete identification of the stinging insect. Melittin, known for its potent pharmacological activity and possibly responsible for most of the side effects in bee venom immunotherapy, can probably not be excluded from therapeutic venom preparations since IgE antibodies to the melittin preparation were detected in one third of the cases.

Bee Venoms

Antigenic relationship between the venom of the night adder Causus maculatus and venoms of other viperids.

Monovalent antivenoms were raised in mice against the venoms of Causus maculatus, Vipera ammodytes, Echis carinatus, Cerastes cerastes, Bitis arietans, Agkistrodon rhodostoma and Bothrops atrox. These antivenoms as well as four commercially available antivenoms were tested against the venoms of 15 viperid species by means of immunoelectrophoresis and/or ELISA. Cross-reactive protein bands were determined by immunoblot. ELISA cross-reactions of C. maculatus antivenom were low with all heterologous venoms. When investigating the other viperine antivenoms in ELISA stronger cross-reactions were observed with several heterologous venoms. In immunoblot, two heterologous antivenoms cross-reacted with one or two protein bands of C. maculatus venom whereas there were at least four heterologous antivenoms cross-reacting with each of the other venoms. The findings indicate that there is little antigenic affinity between C. maculatus venom and the other venoms investigated. Broad in vitro cross-reactions between viperine antivenoms and Causus venom which were reported in literature seem to be attributable to the use of antivenoms of commercial grade. Specificity of commercially produced, mono- or polyvalent antivenoms may not be strictly limited to those venoms, against which potency is claimed on the label of the product.

Animals

Venom immunotherapy: 10 years of experience with administration of single venoms and 50 micrograms maintenance doses.

For the past 10 years, we have administered venom immunotherapy with single venoms, whenever it is possible, and maintenance doses of 50 micrograms. The choice of venoms was based on clinical history, skin test reactions, and a knowledge of venom cross-reactivity. There have been 258 re-stings in 108 patients with only three systemic reactions (2.7% per patient; 1.2% per sting). Two of these re-stings reactions were very mild, hives and facial edema, in patients who had had initial severe anaphylaxis. Five other patients had transient ill-defined symptoms, not considered allergic after re-stings. The patients covered a wide age range. Twenty-seven patients, nine under age 16 years, had initial dermal reactions only, and 44 patients had severe anaphylaxis. Most patients had multiple positive skin tests. Seventy-five patients received single venoms (yellow jacket, 58; honeybee, 15; hornet, 2), and 30 patients received two venoms. Re-stings occurred from 1 month to 8 years, (mean, 2 years) after starting treatment. Results indicate that this approach with 50 micrograms top doses and single venom immunotherapy may be sufficient in most patients with an associated decrease in the cost as well as possible increased morbidity associated with the use of multiple venom antigens.

Adolescent

Venomous Lepidoptera: defensive toxin systems, venom composition, and clinical significance.

Venomous Lepidoptera constitute an underrecognized yet medically significant group of toxin-producing arthropods that employ contact-mediated defensive envenomation through specialized integumentary structures such as setae, spines, and scoli. Unlike actively stinging arthropods, these insects deliver venom passively upon contact, eliciting a diverse spectrum of clinical manifestations collectively termed lepidopterism. Clinical outcomes range from localized pain and dermatitis to severe systemic effects, including hemorrhagic syndromes, complement activation, and chronic inflammatory disorders. Recent advances in proteomic and transcriptomic technologies have transformed our understanding of lepidopteran venoms, revealing unexpectedly complex toxin repertoires comprising serine proteases, phospholipases, pore-forming proteins, disulfide-rich peptides, neuroactive RF-amide peptides, and immune-modulating components. These findings have provided new insights into the molecular basis of toxicity, host-pathogen interactions, and the evolutionary diversification of venom systems within Lepidoptera. This review synthesizes current knowledge on the morphology of venom-delivery structures, venom composition, mechanisms of action, and associated clinical manifestations, while highlighting medically important taxa, particularly species of the genus Lonomia. The successful development of antivenom against Lonomia envenomation underscores the translational relevance of lepidopteran toxin research and its potential for therapeutic innovation. By integrating molecular, clinical, and evolutionary perspectives, this review repositions venomous Lepidoptera as a legitimate and important component of arthropod toxinology. Furthermore, it identifies critical methodological limitations and key knowledge gaps, providing a framework for future investigations aimed at advancing our understanding of toxin biology, immunopathology, and the development of novel biomedical applications.

Animals

Immunotherapy with honeybee venom and yellow jacket venom is different regarding efficacy and safety.

Venom immunotherapy (VIT) for Hymenoptera allergy is accepted as safe and effective. However, widely varying success rates and frequencies of side effects are reported. Differences between various Hymenoptera species could account for these diverging results. We therefore analyzed 205 patients with a history of systemic allergic reactions to either honeybee (148 patients) or yellow jacket stings (57 patients) during VIT. All patients had a positive skin test to the respective venom before VIT, were monitored for side effects of VIT, and submitted to a sting challenge while they were receiving VIT. Patients with honeybee-venom allergy had a higher sensitivity in both skin tests (p less than 0.05) and RAST (p less than 0.001) than patients with yellow jacket-venom allergy. They developed systemic side effects to VIT injections significantly more often (41% versus 25%; p less than 0.01) and also reacted more frequently to the sting challenge (23% versus 9%; p less than 0.01) than patients with yellow jacket-venom allergy. We conclude that results obtained from studies on the allergy to one Hymenoptera venom cannot be extrapolated to allergies to other Hymenoptera venoms.

Acute Disease

Clinical correlation of the venom-specific IgG antibody level during maintenance venom immunotherapy.

Allergen immunotherapy is associated with a significant increase of specific IgG antibodies that have been suggested as a mechanism of action and as a marker of efficacy for immunotherapy. The value of venom-specific IgG antibody determinations as a measure of clinical protection against sting anaphylaxis has been difficult to prove in individual patients. We performed 211 insect sting challenges in 109 patients over a 4-year period to determine the significance of venom IgG levels 3 micrograms/ml or lower. Systemic symptoms occurred in only 1.6% of those with venom IgG more than 3 micrograms/ml, but in 16% of those with less than 3 micrograms/ml IgG, and notably in 26% of patients with low venom IgG who had received less than 4 years of treatment. The venom IgG level had no predictive value in patients who had received more than 4 years of therapy. Honeybee sting data were inconclusive because of the small number of subjects. We conclude that low venom-specific IgG levels are associated with an elevated risk of treatment failure during the first 4 years of immunotherapy with yellow jacket or mixed vespid venoms.

Adult

The use of enzyme-linked immunosorbent assay for the quantitation of Calloselasma rhodostoma (Malayan pit viper) venom and venom antibodies.

The specificity and sensitivity of an indirect and two (an 'ordinary' and a 'rapid') double sandwich enzyme-linked immunosorbent assay (ELISA) procedures for the quantitation of Calloselasma rhodostoma (Malayan pit viper) venom were examined. The three assays were equally sensitive and the accuracy of the assays was not substantially affected by individual variation in the venom composition. The specificity of the assays was examined against 26 venoms from snakes of the families Viperidae and Elapidae. While the double sandwich ELISA procedures were sufficiently specific to be used in the clinical immunodiagnosis of C. rhodostoma bite in Malaysia, the indirect ELISA procedure exhibited extensive cross-reactivity with other Malaysian pit viper venoms. Attempts were made to improve the specificity of the indirect ELISA procedure for the quantitation of C. rhodostoma venom. A 'low ELISA cross-reactivity' venom fraction (termed VF52) was isolated from C. rhodostoma venom by repeated Sephadex G-100 gel filtration chromatography. The indirect ELISA procedure using antibodies to VF52 as immunoreagent showed an improvement in specificity. The use of the indirect ELISA procedure for the detection of C. rhodostoma antibodies was also examined and the results show that the assay was sufficiently specific to be used for retrospective diagnosis of C. rhodostoma bite in Malaysia, in particular when VF52 was used as the coating antigen.

Antibody Specificity

Snake venom proteinase inhibitors. III. Isolation of five polypeptide inhibitors from the venoms of Hemachatus haemachatus (Ringhal's corbra) and Naja nivea (Cape cobra) and the complete amino acid sequences of two of them.

Five proteinase inhibitors which all inhibit the activity of bovine trypsin [EC 3.4.21.4] were isolated from African Elapid venoms of Hemachatus haemachatus (HHV, Ringhal's cobra) and Naja nivea (NNV, Cape cobra). All the inhibitors were essentially homogeneous by polyacrylamide gel electrophoresis in the presence or absence of sodium dodecylsulfate. Amino acid analysis and terminal analysis also supported their chemical homogeneities, except for one of the two inhibitors from Hemachatus haemachatus venom. The isolated inhibitors had a molecular weight of about 6,500, consisting of 52 to 57 amino acid residues, and they were all devoid of tryptophan. However, their amino acid compositions differed from each other. One of the three inhibitors isolated from Naja nivea venom, designated NNV inhibitor Ia, was unique, in that 4 half-cystinyl residues per mole fof the polypeptide were present, whereas all the others contained six residues. Of the isolated proteinase inhibitors, the complete amino acid sequences of two major inhibitors were established by manual and automatic Edman degradations and standard enzymatic techniques. Each of the inhibitors, designated HHV inhibitor II and NNV inhibitor II, consisted of 57 amino acid with arginine and glycine at the NH2- and COOH-termini, respectively. Both contained six half-cystines in disulfide linkages, and their overall amino acid sequences were similar, showing 91% homology. The two inhibitors differed in sequence by only five amino acid replacements, Asp-3 to Arg; Tyr-17 to Arg; Leu-25 to Arg; Gln-32 to Glu; and Arg-52 to His, in the 57 residue peptide chain. Comparing the amino acid sequences of these two cobra venom inhibitors with those of Russell's viper venom inhibitor II and bovine pancreatic trypsin inhibitor (BPTI), about 50% homology was found in their sequences. The 6 half-cystinyl residues of these inhibitors were in the same linear positions. Moreover, the regions which are structurally and functionally important in the well-known BPTI molecule were found with extremely high sequence homology in the cobra venom inhibitors. These findings strongly suggest that the cobra venom inhibitors as well as Russell's viper inhibitor II have very similar conformations to that established for BPTI.

Amino Acid Sequence

Immunity against the venom of Mexican scorpion Centruroides lumpidus limpidus induced by some proteins from this venom.

A protein fraction, which consisted of at least 12 proteins, was obtained from the venom of Mexican scorpion Centruroides limpidus limpidus. The molecular weights of these proteins ranged between 9,800 and 163,000 daltons. This fraction was separated from the rest of the venom components, which were almost all neurotoxins, by chromatographying the venom obtained by electrical stimulation through a Sephadex G-50M column. This fraction was non-toxic for mice, even at dose of 200 micrograms/mouse. The most important is that it was able to induce immunity against C. l. limpidus venom, since 92.8% of the animals inoculated with three doses survived after the challenge with 39.2 micrograms of venom (2 DL50 for mice of 20 g); on the contrary, 88 min after the challenge, 100% of the control mice had already died. In another experiment, this immunogen was inoculated into mice three times at variable doses. Seven days after the last injection, each mouse was challenged with 19.6 micrograms of venom. In all controls the typical envenomation picture produced by scorpion venom was developed, and death was registered in 19% of the animals. In contrast, 87% of mice immunized with the highest dose failed to show signs of envenomation or died throughout the observation time. Only two immunized animals (13%) showed mild tachycardia and hyperpnea at 120 min post-challenge. Immunoelectrophoresis and immunodiffusion tests revealed that these proteins induced antibodies against components of the most toxic fraction.

Animals

A nontoxic derivative of Bothrops jararaca venom suitable to generate antibodies against the native venom.

Bothrops jararaca venom was toxoided by stepwise iodination with cold iodine, and doses up to 30 LD50 were non-lethal by i.p. route (BICALHO et al., 1990). Groups of mice injected chronically with the native, or the iodinated venom, have been subjected to histological examination. In the native group, in the spleen, around the white pulp, an acellular, amorphous eosinophilic substance, metachromatic to Methyl Violet, PAS positive, and dichroic to Congo Red under polarized light, was present. Strong congestion in the liver, kidneys and lungs was found. The salivary glands were replenished with an amorphous substance in the serosal acini. The groups injected with the iodinated venom only show discrete alterations, more akin to the control group. The anavenin was immunogenic. Antibody generation in mice and rabbits was detected by ELISA. In mice, active protection against challenge with native venom was presented. The iodinated venom generated a rabbit antiserum with strong lines in gel immunoprecipitation against the lethal venom. A minimum neutralization titer of 2.3 mg ml-1 against the native venom was attained in the first cycle (28 days) of immunization. After 3 cycles (100 days), the protection rose to 5.1 mg ml-1.

Animals

Viper venoms and coumarin-induced prothrombin. A comparison of several one-stage methods employing three different venoms as thromboplastins.

Three venoms obtained from three vipers, namely Echis carinatus, Notechis scutatus scutatus and Oxyuranus scutellatus, have been used as thromboplastin in a one-stage assay of coumarin-induced prothrombin. Regardless of the venom used, prothrombin resulted to be low in coumarin-treated patients. The mean values obtained were 27.2, 33.6, and 24.2%, respectively. These values were comparable to those obtained by means of the classical one-stage method (24.8%). A good correlation was observed among the different methods. However, the levels observed using the Notechis scutatus scutatus venom method were slightly higher as compared to those obtained by means of the other viper venoms and by means of the classical one-stage method. The three viper venoms used seem unable to activate coumarin-induced prothrombin. The levels obtained were in fact, in each instance, definitely lower than those observed immunologically. Methods which employ these viper venoms may be used in the evaluation of prothrombin in coumarin-treated patients.

Animals

Neutralization of myotoxic activity of Bothrops venoms by antisera to purified myotoxins and to crude venoms.

A phospholipase myotoxin (MOO-1) and a non-phospholipase myotoxin (JSU-5) were studied for their antigenic cross-reactivity and neutralization by different antisera. Antisera against JSU-5 and MOO-1 reacted equally with both myotoxins in ELISA assays. The specificity of these antisera was also similar, recognizing the same 14,000-18,000 mol. wt components in the venoms of Bothrops jararacussu, Bothrops moojeni, Bothrops neuwiedi and Bothrops pradoi. Using creatine kinase assays, JSU-5 myotoxicity was completely neutralized by B. jararacussu antivenom or anti-JSU-5 antibodies and partially neutralized by B. moojeni antivenom or anti-MOO-1 antibodies. MOO-1 myotoxicity was completely neutralized by antisera against JSU-5 and MOO-1 and B. jararacussu antivenom, and only partially neutralized by B. moojeni antivenom. B. jararacussu venom induced high titres of antibodies against purified myotoxins. This antiserum completely inhibited the myotoxicity of the homologous venom and significantly reduced the myotoxicity of the remaining myotoxin-containing venoms. It is suggested that B. jararacussu venom is a good immunogen to induce antibodies against myotoxins present in the venoms of the different species of Bothrops.

Animals

In-hospital sting challenge in insect venom-allergic patients after stopping venom immunotherapy.

Immunotherapy (IT) in venom-allergic patients has been demonstrated to provide a highly efficient protection from severe reactions to a re-sting. It is not known whether this protection will persist after IT is stopped in patients with remaining venom sensitivity. In 25 adult patients with a previous severe systemic reaction to a Hymenoptera insect sting, 28 in-hospital sting challenges after stopping IT resulted in no systemic reactions. The mean duration of venom IT was 42.8 months (range, 36 to 83 months), and the mean time interval from the time IT was stopped until sting challenge was, in mean, 25.2 months (range, 12 to 36 months). The mean venom-specific IgE after stopping IT was 2.4 PRU/ml (range, 0 to 16.9 PRU/ml), at the day of sting challenge, 2.7 PRU/ml (range, 0 to 22 PRU/ml), and 2 weeks later, 2.4 PRU/ml (range, 0.02 to 27.8 PRU/ml). These changes in IgE were not significant. Venom-specific IgG concentration when IT was stopped was 64 PU/ml (range, 20 to 144 PU/ml), decreasing significantly to the day of sting challenge to 41.1 PU/ml (range, 13 to 84 PU/ml), and 2 weeks later, a significant increase to a mean of 53.5 PU/ml (range, 12 to 117 PU/ml) was found. Our results suggest that venom IT may be stopped after 3 years, regardless of the level of specific antibodies. To confirm this finding, a larger number of patients should be studied.

Adult

Use of HPLC to demonstrate variation of venom toxin composition in the Thailand cobra venoms Naja naja kaouthia and Naja naja siamensis.

The composition of the venoms of Naja naja kaouthia and Naja naja siamensis from different commercial sources has been investigated using both ion-exchange and reverse-phase high-pressure liquid chromatography (RP-HPLC) in order to investigate variation in toxin contents. The venoms contained identical major toxin components, although in different relative concentrations. The venom collected separately from the left and right glands of individual snakes were virtually the same as judged by RP-HPLC. The cytotoxin CT-II, which was previously only reported to be present in Naja naja siamensis venom, was detected in all the venoms investigated. Two long neurotoxin homologues have also been isolated.

Amino Acids

Some pharmacological properties of the venom, venom fractions and pure toxin of the yellow-bellied sea snake Pelamis platurus.

The effects of the crude venom, four partially purified venom fractions and pure toxin (Pelamis toxin alpha) from yellow-bellied sea snake, Pelamis platurus, on respiration, blood pressure, heart and skeletal muscle of rabbits have been examined. Results indicated that crude venom, a partially purified toxic fraction and Pelamis toxin alpha caused initial respiratory stimulant effects followed by respiratory paralysis. In most cases, respiratory paralysis occurred before a profound fall in arterial pressure. Depression of the twitch response to nerve stimulation was observed in the tibialis anterior muscle. No significant change in the electrocardiogram was seen. Three partially purified non-toxic fractions of the crude venom induced transient respiratory stimulant effects. It was concluded that the crude venom and Pelamis toxin alpha had an identical mode of action and that they caused respiratory paralysis in rabbits.

Animals

Effect of concanavalin A on black widow spider venom activity at the neuromuscular junction: implications for mechanisms of venom action.

Concanavalin A (Con A) inhibits black widow spider venom-induced transmitter release at both tissue-cultured and adult neuromuscular junctions and also inhibits the venom-induced destruction of cultured neurites. This inhibitory action is partially or completely prevented by prior treatment with colchicine. Neither colchicine nor Con A interacts significantly with depolarization-induced transmitter release. These results are analogous to those obtained from experiments on lymphocyte surface receptor capping. They suggest that redistribution of neuronal membrane components may be a crucial step in spider venom action. This membrane redistribution appears to be modulated in neurons, as in other cell types, by microtubule-microfilament array. How such a redistribution causes increased transmitter release cannot as yet be specified. Changes in the ionic permeability of sodium and potassium were examined as likely mechanisms. Increased sodium influx (and seondary release of calcium from intracellular stores) cannot be the basis for spider venom action. Increased potassium efflux remains a possibility, but is not consistent with all of the data. Other possible mechanisms are also suggested.

Animals