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At least 379 records · Page 21Linked to original sources
PubMed2006

Metabolic, respiratory and cardiovascular responses to acute and chronic hypoxic exposure in tadpole shrimp Triops longicaudatus.

Hypoxic exposure experienced during sensitive developmental periods can shape adult physiological capabilities and define regulatory limits. Tadpole shrimp were reared under normoxic (19-21 kPa O(2)), moderate (10-13 kPa O(2)) or severe (1-3 kPa O(2)) hypoxic conditions to investigate the influence of developmental oxygen partial pressure (P(O(2))) on adult metabolic, respiratory and cardiovascular physiology. Developmental P(O(2)) had no effect on metabolic rate or metabolic response to hypoxic exposure in adults. All rearing groups decreased O(2) consumption as water P(O(2)) decreased. Heart rate, stroke volume and cardiac output were independent of P(O(2)) down to 5 kPa O(2) in all rearing groups. Below this, cardiac output was maintained only in tadpole shrimp reared under severe hypoxic conditions. The enhanced ability to maintain cardiac output was attributed to an increase in hemoglobin concentration and O(2)-binding affinity in those animals. Oxygen-delivery potential was also significantly higher in the group reared under severe hypoxic conditions (1,336 microl O(2) min(-1)) when compared with the group reared under normoxic conditions (274 microl O(2) min(-1)). Differences among the rearing groups that were dependent on hemoglobin were not considered developmental effects because hemoglobin concentration could be increased within seven days of hypoxic exposure independent of developmental P(O(2)). Hypoxia-induced hemoglobin synthesis may be a compensatory mechanism that allows tadpole shrimp to regulate O(2) uptake and transport in euryoxic (O(2) variable) environments. The results of this study indicate that increased hemoglobin concentration, increased O(2)-binding affinity and transient decreases in metabolic demand may account for tadpole shrimp hypoxic tolerance.

Animals↗
PubMed1998

Burrow ventilation in the tube-dwelling shrimp Callianassa subterranea (Decapoda: thalassinidea). I. Morphology and motion of the pleopods, uropods and telson.

The morphology of the pleopods, uropods and telson of the tube-dwelling shrimp Callianassa subterranea have been studied using dissection microscopy and scanning electron microscopy. The kinematics of these appendages were examined by motion analysis of macro-video recordings of ventilating shrimps in transparent artificial burrows. The pleopods show the usual crustacean biramous anatomy, but all segments are rostro-caudally flattened. The protopodite bears a triangular medially oriented endopodite and a scoop-shaped exopodite. The contralateral endopodites are linked by the appendix interna, ensuring a perfect phase relationship between contralateral pleopods. The outer rims of the exopodites are fringed with long fern-leaf-like plumose setae bearing flattened setules. These setae have very mobile joints and can be turned caudally. The slits between contralateral endopodites have rims of leaf-like setae as well. Setae of the same leaf-like type fringe the uropods, but these are non-motile. The telson has a narrow fringe of leaf-like setae, locally interrupted by long mechanoreceptory setae. A shrimp, wandering through the burrow or resting, holds its pleopods against the abdomen with the exopodites and their setal fringes retracted medially. The uropods are folded medially as well, probably to reduce the shrimp's drag. During ventilation, the uropods are extended against the tube wall, leaving only a small opening for flow ventral from the telson, and the pleopods beat at a frequency of approximately 1 Hz (0.9+/-0.2 Hz). Fourier analysis of pleopod kinematics showed that the motion pattern of the first flow-generating pleopod pair (PP1) consisted mainly of the first harmonic (75 %) and to a lesser extent of the third harmonic (20 %), resulting in almost perfect sinusoidal motion. The motion patterns of PP2 and PP3 could be modelled by assigning pure sinusoids with a 120 degrees phase shift and a rostro-caudal ranking to the three pairs of pleopods.

Animals↗
PubMed2004

Cloning and molecular characterization of heat shock cognate 70 from tiger shrimp (Penaeus monodon).

We cloned the complementary deoxyribonucleic acid (cDNA) of the heat shock cognate 70 (hsc70) gene of tiger shrimp (Penaeus monodon). It was 2207 bp long and included a 1959-bp coding region, a 40-bp flanking region at the 5' end, and a 208-bp flanking region at the 3' end. The deduced, 652-amino acid sequence had a molecular mass of 71 481 Da and an estimated isoelectric point (pI) of 5.2. Based on phylogenetic analysis, the gene is clustered with the hsc70 proteins of invertebrates and vertebrates. In native gel electrophoresis, recombinant P. monodon hsc70 expressed in an Escherichia coli system is tightly associated with carboxymethylated alpha-lactalbumin (CMLA), which indicates that hsc70 probably functions as a chaperone. In an in vitro adenosine triphosphatase assay, recombinant hsc70 hydrolyzed adenosine triphosphate to adenosine-5'-diphosphate and increased hydrolysis activity by binding to unfolded peptide, CMLA. In situ hybridization using an antisense riboprobe revealed that the hsc70 gene was active in most tissues of unstressed shrimp. The expression of hsc70 messenger ribonucleic acid (mRNA) in hemocytes increased 2- to 3-fold at the first hour after shrimp experienced heat shock and 0.5-hour recovery. Hsc70 mRNA decreased gradually to the background level. Cloning and characterizing the P. monodon hsc70 gene is the first, crucial step in studying the relationship of heat shock proteins with the stress or immune responses of shrimp.

Adenosine Triphosphatases↗
PubMed2001

Studies on digestive proteases from midgut glands of a shrimp, Penaeus indicus, and a lobster, Nephrops norvegicus: Part 1. Proteolytic activity.

Digestive gland protease pH optima and specific activities determined in Penaeus indicus with casein, azocasein, Azocoll, and Congo red fibrin as substrates were pH 7.7-9.2, 210-371 micromol of tyrosine/mg of homogenate protein/min; pH 7.8, 36; pH 6.0-7.0, 7; and pH 8.9-9.2, 7A delta0.001 U/mg of homogenate protein/min, respectively. Activity in the shrimp was stable during frozen storage but relatively labile and very low (1.043 azocasein units) in the Norwegian lobster, Nephrops norvegicus. The high activity in shrimp is significant in aquaculture and may be a source of proteolytic enzymes for industrial use. The rapid deterioration after landing may be a consequence of the high and stable activity. The low activity in the lobster may present a problem in culture and requires a more critical choice of feed as well as further investigation. 4-(2-Aminoethyl)-benzenesulfonyl fluoride hydrochloride was a very convenient, fast-acting, and effective inhibitor of shrimp trypsin and chymotrypsin but did not completely inhibit general protease activity in shrimp and had a negligible effect on the lobster. A significant component of that activity may be from nonserine proteases (such as the exoproteases carboxypeptidase A and B and the leucine aminopeptidases), whose proportion relative to the serine proteases may be greater in the lobster.

Animal Feed↗
PubMed2003

Influence of salinity on the bioaccumulation and photoinduced toxicity of fluoranthene to an estuarine shrimp and oligochaete.

The effect of salinity on the photoinduced toxicity of waterborne fluoranthene to larvae of the grass shrimp (Palaemonetes pugio) and tubificid oligochaete worms (Monopylephorus rubroniveus) was studied in a laboratory system under simulated sunlight. In the grass shrimp toxicity tests, five concentrations of fluoranthene (0, 3.6, 7.3, 13.8, and 29.0 microg/L) and four salinities (6.9, 14.5, 21.2, and 28.6 per thousand) were achieved. In the oligochaete toxicity tests, five concentrations of fluoranthene (0, 0.8, 1.4, 3.3, and 7.7 microg/L) and four salinities (7.1, 13.3, 20.5, and 27.6 per thousand) were achieved. Salinity had no effect on either the photoinduced toxicity or the bioaccumulation of fluoranthene in the grass shrimp. However, the highest level of salinity decreased the median lethal time for the oligochaete. Bioaccumulation of fluoranthene was inversely related to salinity for the oligochaete. Additional experiments demonstrated an inverse relationship between salinity and short-term osmotic weight change in the oligochaete. Weight of the grass shrimp larvae was not affected by salinity. These findings show that salinity can influence the toxicity and bioaccumulation of fluoranthene in some estuarine organisms. The influence of salinity on these populations may be related to physiological responses associated with internal osmotic volume changes. Thus, salinity needs to be taken into account when assessing the risk of photoactivated polycyclic aromatic hydrocarbon (PAH) to at least some estuarine species.

Animals↗
PubMed2006

Acute toxicity of pyrithione antifouling biocides and joint toxicity with copper to red sea bream (Pagrus major) and toy shrimp (Heptacarpus futilirostris).

We evaluated the median lethal concentrations (LC50s) of the pyrithione (PT) antifoulants copper pyrithione (CuPT) and zinc pyrithione (ZnPT) to a teleost, red sea bream (Pagrus major), and a crustacean, toy shrimp (Heptacarpusfutilirostris). The 96-h LC50 values of CuPT and ZnPT, on the basis of actual concentrations, were 9.3 and 98.2 R.g/L, respectively, for red sea bream and 2.5 and 120 microg/L, respectively, for toy shrimp. Histological observations revealed that the secondary lamellae of the gill filaments of the experimental fish were heavily damaged after exposure to the PTs, suggesting that fatal hypoxemia was one cause of death. Because CuPT and ZnPT are usually used in combination with Cu, we also estimated the joint toxicities of the PTs with Cu using the LC50 values of the PTs and those of Cu (84.4 and 113 microg/L for red sea bream and toy shrimp, respectively). The results suggested that the joint toxicity of the ZnPT and Cu mixture is more than the additive toxicities of CuPT and Cu, especially in toy shrimp. The enhancement of toxicity in the mixture was inferred to be caused by conversion of ZnPT to the more toxic CuPT in the presence of Cu.

Animals↗
PubMed2000

Shrimp culture in Thailand: environmental impacts and social responses.

Black tiger shrimp (Penaeus monodon) is a major aquaculture commodity among Southeast Asian producers and remains a popular food export world-wide. Food brokers in Japan and the United States purchase huge quantities of these farmed shrimp and return significant foreign exchange earnings to developing nations like Thailand, a major producer and exporter since the early 1990s. However, coastal areas cannot sustain intensive shrimp farm production and local growers often end up in debt. Can the needs of farm communities around the world be suitably met when they join into a corporate-managed and export-oriented food system? What are the sustainable benefits and eventual costs to susceptible localities? The shrimp industry in Thailand reveals the difficult terrain to cross and powerful obstacles to overcome if authentic sustainable development is to be realized.

Journal Article↗
PubMed1996

Retinal anatomy of a new species of bresiliid shrimp from a hydrothermal vent field on the Mid-Atlantic Ridge.

A new species of shrimp (Rimicaris sp.) was recently collected from the Snake Pit hydrothermal vent field on the Mid-Atlantic Ridge. Until the discovery in 1989 that the deep-sea, hydrothermal vent species, Rimicaris exoculata, possessed a hypertrophied dorsal eye, everyone believed that animals recovered from vent environments were blind. Like R. exoculata, Rimicaris sp., a small orange bresiliid shrimp, has an enlarged dorsal eye specialized for detecting light in a very dim environment instead of the expected compound eye. The individual lenses characteristic of a compound eye adapted for imaging have been replaced in Rimicaris sp. by a smooth cornea underlain by a massive array of photosensitive membrane. The number of ommatidia in this species is about the same as in shrimp species that live at the surface; however, the photoreceptors are larger in the deep-sea species and the shape of the photoreceptors is markedly different. The light-sensitive region of the photoreceptor is much larger than those of other shrimp and the rest of the receptor is much smaller than normal. All screening pigment has moved out of the path of incident light to a position below the retina, and the reflecting pigment cells have adapted to form a bright white diffusing screen between and behind the photoreceptors. The ultrastructure of the microvillar array comprising the rhabdom is typical for decapod crustaceans; however, there is a much greater volume density of rhabdom (80% to 85%) than normal. There is no ultrastructural evidence for cyclic rhabdom shedding or renewal. Rimicaris sp. has apparently adapted its visual system to detect the very dim light emitted from the throats of the black smoker chimneys around which it lives.

Animals↗
PubMed2004

Chemical and visual communication during mate searching in rock shrimp.

Mate searching in crustaceans depends on different communicational cues, of which chemical and visual cues are most important. Herein we examined the role of chemical and visual communication during mate searching and assessment in the rock shrimp Rhynchocinetes typus. Adult male rock shrimp experience major ontogenetic changes. The terminal molt stages (named "robustus") are dominant and capable of monopolizing females during the mating process. Previous studies had shown that most females preferably mate with robustus males, but how these dominant males and receptive females find each other is uncertain, and is the question we examined herein. In a Y-maze designed to test for the importance of waterborne chemical cues, we observed that females approached the robustus male significantly more often than the typus male. Robustus males, however, were unable to locate receptive females via chemical signals. Using an experimental set-up that allowed testing for the importance of visual cues, we demonstrated that receptive females do not use visual cues to select robustus males, but robustus males use visual cues to find receptive females. Visual cues used by the robustus males were the tumults created by agitated aggregations of subordinate typus males around the receptive females. These results indicate a strong link between sexual communication and the mating system of rock shrimp in which dominant males monopolize receptive females. We found that females and males use different (sex-specific) communicational cues during mate searching and assessment, and that the sexual communication of rock shrimp is similar to that of the American lobster, where females are first attracted to the dominant males by chemical cues emitted by these males. A brief comparison between these two species shows that female behaviors during sexual communication contribute strongly to the outcome of mate searching and assessment.

Analysis of Variance↗
PubMed1999

Results from black tiger shrimp penaeus monodon culture ponds stocked with postlarvae PCR-positive or -negative for white-spot syndrome virus (WSSV).

Commercial, intensive, earthen shrimp ponds (188) in southern Thailand were stocked with postlarvae (PL) of Penaeus monodon that had tested positive or negative for white-spot syndrome virus (WSSV) infection by polymerase chain reaction (PCR) assay. All the PL were grossly healthy. At 2 wk intervals after stocking, shrimp from each pond were examined for gross WSSV lesions and tested for WSSV by PCR. Shrimp from all the ponds stocked with WSSV-PCR-positive PL (Group 0, n = 43) eventually showed gross signs of white-spot disease (WSD) at an average of 40 d after stocking. Of the remaining ponds stocked with WSSV-PCR-negative PL (n = 145), some remained WSSV-PCR-negative throughout the study (Group 5, n = 52), while others (93) became WSSV-PCR-positive after stocking, during the first month (Group 1, n = 23), second month (Group 2, n = 40), third month (Group 3, n = 24), or fourth month (Group 4, n = 6). Crop failure was defined as a pond drain or forced harvest before 14 wk or 98 d of cultivation. For Group 0 the proportion of ponds failing was 0.953, while it was only 0.019 for Group 5. Thus, the relative risk of failure for Group 0 was approximately 50 times that of Group 5. The relative risk of failure for Group 0 was also 3 times that for ponds stocked with WSSV-PCR-negative PL. Obviously, not all WSSV outbreaks resulted in crop failure. Of the 93 ponds stocked with PCR-negative PL that later yielded WSSV-PCR-positive shrimp, 53% reached successful harvest. The study showed that PCR screening of PL and rejection of WSSV-positive batches before stocking could greatly improve the chances of a successful harvest.

Animals↗
PubMed2000

A new bacterial white spot syndrome (BWSS) in cultured tiger shrimp Penaeus monodon and its comparison with white spot syndrome (WSS) caused by virus.

This paper describes a new bacterial white spot syndrome (BWSS) in cultured tiger shrimp Penaeus monodon. The affected shrimp showed white spots similar to those caused by white spot syndrome virus (WSSV), but the shrimp remained active and grew normally without significant mortalities. The study revealed no evidence of WSSV infection using electron microscopy, histopathology and nested polymerase chain reaction. Electron microscopy indicated bacteria associated with white spot formation, and with degeneration and discoloration of the cuticle as a result of erosion of the epicuticle and underlying cuticular layers. Grossly the white spots in BWSS and WSS look similar but showed different profiles under wet mount microscopy. The bacterial white spots were lichen-like, having perforated centers unlike the melanized dots in WSSV-induced white spots. Bacteriological examination showed that the dominant isolate in the lesions was Bacillus subtilis. The occurrence of BWSS may be associated with the regular use of probiotics containing B. subtilis in shrimp ponds. The externally induced white spot lesions were localized at the integumental tissues, i.e., cuticle and epidermis, and connective tissues. Damage to the deeper tissues was limited. The BWS lesions are non-fatal in the absence of other complications and are usually shed through molting.

Animals↗
PubMed2000

A logistic regression of risk factors for disease occurrence on Asian shrimp farms.

Serious shrimp-disease outbreaks have reduced shrimp production and slowed industry growth since 1991. This paper tests factors such as farm sitting and design, and farm-management practices for relationships with disease occurrence. Logistic regression is used to analyze farm-level data from 3951 shrimp farms in 13 Asian countries. Disease occurrence is modeled as a 0-1 variable where 1 = disease loss of > or = 20% to any 1 crop, and 0 = losses of < 20%. Logistic regression is performed for each of 3 levels of shrimp culture intensity, i.e. extensive, semi-intensive, and intensive. Attempts to apply logistic regression models to each country were not successful due to insufficient data for most countries. Factors affecting disease occurrences were quite different for different farming intensities. Farms that had larger pond production areas, with larger number of farms discharging effluent into their water supply canals, and removed silt had greater disease occurrence. On the other hand, farms that practiced polyculture and took water from the sea through a canal had lower disease occurrence.

Animals↗
PubMed2002

Detection of white spot syndrome virus (WSSV) of shrimp by means of monoclonal antibodies (MAbs) specific to an envelope protein (28 kDa).

The vp28 gene encoding an envelope protein (28 kDa) of white spot syndrome virus (WSSV) was amplified from WSSV-infected tiger shrimp that originated from Malaysia. Recombinant VP28 protein (r-28) was expressed in Escherichia coli and used as an antigen for preparation of monoclonal antibodies (MAbs). Three murine MAbs (6F6, 6H4 and 9C10) that were screened by r-28 antigen-based enzyme-linked immunosorbent assay (ELISA) were also able to recognize viral VP28 protein as well as r-28 on Western blot. Three non-overlapping epitopes of VP28 protein were determined using the MAbs in competitive ELISA; thus, an antigen-capture ELISA (Ac-ELISA) was developed by virtue of these MAbs. Ac-ELISA can differentiate WSSV-infected shrimp from uninfected shrimp and was further confirmed by a polymerase chain reaction (PCR) and Western blot. Approximately 400 pg of purified WSSV sample and 20 pg of r-28 could be detected by Ac-ELISA, which is comparable in sensitivity to PCR assay but more sensitive than Western blot in the detection of purified virus. Hemolymph and tissue homogenate samples collected from a shrimp farm in Malaysia during December 2000 and July 2001 were also detected by Ac-ELISA and PCR with corroborating results.

Animals↗
PubMed2003

Time-course and levels of apoptosis in various tissues of black tiger shrimp Penaeus monodon infected with white-spot syndrome virus.

This study focused on apoptosis in various tissues of the black tiger shrimp Penaeus monodon following white spot syndrome virus (WSSV) injection. The study included: (1) light microscopy (LM) and transmission electron microscopy (TEM) of various tissues; (2) fluorescent LM of nuclear DNA by staining with 4, 6-diamidine-2-phenyl indole dihydrochloride (DAPI) and TdT-mediated dUTP nick-end labelling (TUNEL) techniques; and (3) determination of caspase-3 activity. Juvenile P. monodon were injected with WSSV, and several tissues of ectodermal and mesodermal origin were studied at different intervals after injection. The total haemocyte count had decreased to one-tenth of its original level 60 h after WSSV injection. By LM, extensive destruction by WSSV was observed in the stomach epithelium, gills, hematopoietic tissue, hemocytes and the heart, but the most severely affected tissue was the subcuticular epithelium. TEM revealed that at 6 h post-injection (p.i.) the chromatin of infected nuclei was marginated, and by 24 h p.i. the nuclei were filled with enveloped and non-enveloped WSSV virions. At later stages of the infection, the nucleus extruded WSSV particles. Chromatin margination and nuclear condensation and fragmentation (i.e. signs of apoptosis) were observed as early as 6 h p.i. in all affected tissues, but occurred in cells without WSSV virions rather than in cells with virions. The occurrence of apoptosis was supported by data obtained using TUNEL and by DAPI-staining and progressed from 6 to 60 h p.i. In addition, caspase-3 activity in WSSV-infected shrimp was about 6-fold higher than that in uninfected shrimp. The data strongly suggests that apoptosis occurs following WSSV infection in P. monodon, but the extent to which it contributes to shrimp mortality requires further investigation.

Animals↗
PubMed2004

Development of monoclonal antibodies for detection of necrotizing hepatopancreatitis in penaeid shrimp.

Monoclonal antibodies (MAbs) were produced against necrotizing hepatopancreatitis bacteria (NHP-B) of penaeid shrimp. The MAbs tested in dot-immunoblot (D-IB) assays were capable of detecting the NHP-B in hepatopancreas samples collected from moribund juvenile Litopenaeus vannamei during an experimentally induced NHP-B infection. The MAbs were also screened by immunohistochemistry (IHC) using case submissions that were determined to be infected not only by histology, but also polymerase chain reaction (PCR) and in situ hybridization (ISH) assays using specific digoxigenin (DIG)-labeled probes on histological sections prepared from naturally infected shrimp. Two of the MAbs were chosen for development of detection methods for NHP. The MAbs were tested using IHC methods on Davidson's alcohol-formalin-acetic acid (AFA) fixed tissue sections and identified NHP-B infected cells and tissues in a pattern similar to that seen with DIG-labeled NHP-specific gene probes. None of the MAbs reacted with tissue from specific pathogen-free (SPF) shrimp or with shrimp tissues infected with a rickettsia-like bacteria, Vibrio sp., Campylobacter sp., and Spiroplasma sp. The MAbs were found to be negative against these other organisms, demonstrating that they are species specific and useful for rapid diagnostic detection of NHP-B.

Animals↗
PubMed1995

[Causative agent of the so-called "light disease of shrimps" is luminescent Vibrio cholerae non-O1].

A number of luminous fresh-water shrimps were found in a fish preserve in Lake Biwa, Shiga Prefecture, in the middle of July, 1994, and most of them died within several hours after collection (the so-called "light disease of shrimp"). Four luminous organisms were isolated from a dead shrimp. Although the phenotypic properties of these strains were similar to those of V. cholerae or V. mimicus, a representative strain, 838-94, was shown to have a high level (79%) of DNA homology with V. cholerae type strain, ATCC 14035 and a low level (45%) of relatedness to V. mimicus type strain, ATCC 33653. Therefore, these isolates were identified as V. cholerae. The four strains fell into serogroup O28 of V. cholerae. On the other hand, none of the isolates had CT nor NAG-ST genes. The results obtained herein clearly demonstrate that these organisms isolated from luminous shrimps are luminescent V. cholerae serogroup O28.

Animals↗
PubMed2003

Proteomics and immunological analysis of a novel shrimp allergen, Pen m 2.

Shellfish are a common cause of adverse food reactions in hypersensitive individuals and shrimp is one of the most frequently reported causes of allergic reactions. A novel allergen from Penaeus monodon, designated Pen m 2, was identified by two-dimensional immunoblotting using sera from subjects with shrimp allergy, followed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of the peptide digest. This novel allergen was then cloned and the amino acid sequence deduced from the cDNA sequence. The cloned cDNA encoded a 356-aa protein with an acetylated N terminus at Ala2, identified by postsource decay analysis. Comparison of the Pen m 2 sequence with known protein sequences revealed extensive similarity with arginine kinase (EC 2.7.3.3) from crustaceans. Pen m 2 was purified by anion exchange chromatography and shown to have arginine kinase activity and to react with serum IgE from shrimp allergic patients and induce immediate type skin reactions in sensitized patients. Using Pen m 2-specific antisera and polyclonal sera from shrimp-sensitive subjects in a competitive ELISA inhibition assay, Pen m 2 was identified as a novel cross-reactive Crustacea allergen. This novel allergen could be useful in allergy diagnosis and in the treatment of Crustacea-derived allergic disorders.

Allergens↗
PubMed2005

Reduced allergenic potency of VR9-1, a mutant of the major shrimp allergen Pen a 1 (tropomyosin).

The major shrimp allergen, tropomyosin, is an excellent model allergen for studying the influence of mutations within the primary structure on the allergenic potency of an allergen; Pen a 1 allows systematic evaluation and comparison of Ab-binding epitopes, because amino acid sequences of both allergenic and nonallergenic tropomyosins are known. Individually recognized IgE Ab-binding epitopes, amino acid positions, and substitutions critical for IgE Ab binding were identified by combinatorial substitution analysis, and 12 positions deemed critical were mutated in the eight major epitopes. The mutant VR9-1 was characterized with regard to allergenic potency by mediator release assays using sera from shrimp-allergic subjects and sera from BALB/c, C57BL/6J, C3H/HeJ, and CBA/J mice sensitized with shrimp extract using alum, cholera toxin, and Bordetella pertussis, as adjuvants. The secondary structure of VR9-1 was not altered; however, the allergenic potency was reduced by 90-98% measuring allergen-specific mediator release from humanized rat basophilic leukemia (RBL) cells, RBL 30/25. Reduced mediator release of RBL-2H3 cells sensitized with sera from mice that were immunized with shrimp extract indicated that mice produced IgE Abs to Pen a 1 and to the same epitopes as humans did. In conclusion, data obtained by mapping sequential epitopes were used to generate a Pen a 1 mutant with significantly reduced allergenic potency. Epitopes that are relevant for human IgE Ab binding are also major binding sites for murine IgE Abs. These results indicate that the murine model might be used to optimize the Pen a 1 mutant for future therapeutic use.

Allergens↗