Host immunoglobulin G titre and antibody activity in haemolymph of the tick, Ornithodoros moubata

Immunoglobulin G (IgG) in tick haemolymph was analysed immunochemically and biochemically for its antigenicity, antibody activity and relative concentration in a soft tick, Ornithodoros moubata (Murray) sensu Walton 1962 (Acari: Argasidae). Ouchterlony immunodiffusion tests showed that haemolymph from a tick engorged on rabbit IgG (or human IgG) through an artificial membrane, reacted with anti-rabbit IgG (anti-human IgG) but not with anti-human IgG (anti-rabbit IgG). This indicates that haemolymph of the fed tick contains IgG with a similar antigen specificity to host blood IgG. IgG from tick haemolymph was demonstrated by enzyme immunoassay to have the same antibody activity as ingested IgG. The IgG concentration in tick haemolymph was measured by a quantitative single immunodiffusion test. Changes of IgG titre after a bloodmeal were correlated with IgG activity, which was low for 5 days after a bloodmeal and then suddenly increased. The IgG titre reached a maximum 7 days post-engorgement, and remained high for over 4 months during and after oviposition. 125I-labelled IgG was injected into the tick haemocoel to determine the persistence of IgG in the haemolymph. Recovery of labelled IgG was low at 1 and 3 days, and high at 5, 8 and 16 days after engorgement. The data suggest that IgG in haemolymph disappears quickly soon after engorgement possibly by degradation and/or absorption (adhesion to tissues).     

Changes in haemolymph ion concentrations of Astacus astacus L. and Pacifastacus leniusculus (Dana) after exposure to low pH and aluminium

During exposure to soft water, acidified to pH 4.0, the haemolymph concentrations of Na⁺, K⁺, and Cl^– decreased whereas the Ca²⁺ concentration fluctuated in Astacus astacus. The haemocyte content of K⁺ decreased from 9% to 2% of the total haemolymph K⁺ content after exposure to pH 3.7 for 3 days. Within 14 days, 250 µg Al³⁺ l^–1, as Al₂(SO₄)₃ at pH 5.0, reduced the haemolymph Na⁺ content in Astacus astacus and Pacifastacus leniusculus, however, the effects were less pronounced than earlier reported for fish. Disturbed ion regulation, mainly depending on low pH, is thought to contribute to the absence of these species in acid waters.     

非洲钝缘蜱感染Q热立克次体敏感度的测定

Q热立克次体以10^-1—10^-12不同稀释度,用血腔注射法感染非洲钝缘蜱,感染35天,取蜱血淋巴液,分别用Gimenez染色法及免疫荧光技术检查,在10^-1—10^-5的稀释度,两种方法检出率基本相似。10^-6以下各组,免疫荧光尚可检出少数阳性标本,而Gimcnez法则无阳性,前者总阳性率为48.28%,后者为40.68%。感染的蜱悬液接种豚鼠,12组动物血清做Q热补体结合试验全部阳性。动物发病情况如潜伏期长短、发烧天数等似与蜱内立克次体的含量有关。     

Ovarian and haemolymph titres of ecdysteroid during the gonadotrophic cycle in Diploptera punctata

The free (non-conjugated) ecdysteroid in the ovaries during the first gonadotrophic cycle of Diploptera punctata was identified as 20-hydroxyecdysone. The hormone, quantified by radioimmunoassay and by ultraviolet absorbance, was detectable in the ovary toward the end of vitellogenesis; the quantity increased rapidly during chorion formation. Ovaries with chorionated eggs contained 67 μg of 20-hydroxyecdysone per g fresh weight. The haemolymph free-ecdysteroid, not identified physicochemically, was quantified by radioimmunoassays. The highest concentration was observed at adult emergence; the titre declined between days 1–3 and then remained at a relatively constant level through oviposition (which occurs between day 7 and 8); titres in pregnant females were higher. Ovariectomized females exhibited the same pattern of ecdysteroid titres in the haemolymph as the sham operated controls throughout the period corresponding to the first gonadotrophic cycle. Thus the ovary may not be the only source of haemolymph ecdysteroid related to reproduction in adult females.     

Haemagglutinin activity in the haemolymph of individual Acrididae (grasshopper) specimens

Twenty-four individual grasshopper specimens representing four Melanoplus spp. contained similar broad-spectrum haemolymphatic haemagglutinin. The agglutinin activity showed highest titre toward human ABO and rabbit cells among nine types of erythrocytes tested. Titre values differed between individual insects but agglutination specificity toward different erythrocytes was similar. Agglutination of type-O red cells by individual grasshopper haemolymph was inhibited by 34 of 41 tested carbohydrates, carbohydrate derivatives, alcohols and chelating agents. Individual insects showed similar patterns of haemagglutination inhibition. Non-inhibitory compounds were mannose and mannose derivatives (excepting N-acetylneuraminate), several glucose derivatives, amino sugars and ethanol. The observations indicated that haemolymph from an individual grasshopper contained complex heteroagglutinin activity similar to that found in haemolymph pooled from several insects. Determination of minimal effective inhibitor concentrations confirmed the presence of heteroagglutinin activity primarily directed toward galactose and glucose and related α-linked glycosidic derivatives.     

Immunocytochemical and electrophoretic studies on the localization of the major haemolymph proteins (ceratitins) inCeratitis capitata during development

Summary The developmental profile of the major haemolymph proteins (ceratitins) inCeratitis capitata was studied. Ceratitin concentration in the haemolymph decreases dramatically during the last days of pupal life, while the amounts of ceratitins in whole organism extracts remain unchanged. By electrophoretic, immunological and immunofluorescence techniques it was revealed that ceratitins are reabsorbed by the fat body and a fraction of them is deposited in the cuticle. The possible role of ceratitins is discussed.     

Hormonal control of uric acid storage in the fat body during last-larval instar of Manduca sexta

In the last-larval instar of the tobacco hornworm, Manduca sexta, a switch from excretion of uric acid to storage in the fat body occurs during transition from the feeding to the wandering stage. Neuroendocrine control of this change from excretion to storage was demonstrated by neck-ligation experiments with synchronously reared larvae. Results indicate that a neurohormone is released from the head 24–30 hr before the initiation of wandering and coincident with the first release of ecdysone that initiates metamorphosis. Direct involvement of the moulting hormone was shown by the effects of multiple injections of 20-hydroxyecdysone into the abdomen of larvae that had been ligated before the release of hormone. Urate levels in the fat body were 20- to 100-fold higher from hormone-injected larvae as from saline inject controls. Topically applied juvenile hormone or methoprene reversed the 20-hydroxyecdysone-induced storage of urate. Increased levels of uric acid in the haemolymph during pupal development result from the presence of juvenile hormone, and the abrupt decrease in uric acid concentration in the haemolymph just prior to pupal ecdysis results from a decreased titre of juvenile hormone. Applications of methoprene prevented the decrease in uric acid levels in the haemolymph.     

Water balance in Collembola and its relation to habitat selection: Water content,haemolymph osmotic pressure and transpiration during an instar

In the two collembolan species Orchesella cincta and Tomocerus minor the water content, haemolymph osmotic pressure and transpiration rate fluctuate with the feeding rhythm during each instar. The changes in water content, however, are due to changes in dry weight, because the absolute water weight stays constant during the instar.The intake of food is probably the cause of the increase in haemolymph osmotic pressure. Increase of osmotically active substances in the blood and/or blood volume reduction may be responsible for the rise in osmotic pressure. This change in osmotic pressure in turn may affect the responsiveness of the animals to water as well as their feeding behaviour.Changes in the epicuticle and in epidermal cell membranes may cause changes in the rate of transpiration. The high rate observed during ecdysis and during the mid-instar may explain the behaviour of the animals in varied water conditions.Dehydration during the instar causes an equivalent rise in osmotic pressure for both Tomocerus minor and Orchesella cincta. The water loss appears to involve the haemolymph. The physiological state of the animal does not influence the rise in osmotic pressure. There are no signs of any osmoregulation in the two species.     

Ultrastructure of retrocerebral complex of the earwig, Euborellia annulipes, and rôle of aorta as a neurohaemal organ

The ultrastructure of the retrocerebral endocrine-aortal complex of the earwig, Euborellia annulipes has been studied. The space between the inner and outer stromal layers of the aorta is occupied by numerous axon terminals and pre-terminals containing large electron dense granules (NS-I) of approximately 100 to 220 nm and a few axon terminals having small granules (NS-II) of approximately 40 to 90 nm; the former appear to belong to medial neurosecretory A-cells, and the latter to the B-cells of the brain. The corpora cardiaca consist of intrinsic cells with mitochondria and multivesicular bodies. Granules of type NS-II and NS-III are observed in the axon terminals and pre-terminals in the corpora cardiaca. The NS-II are identical to those found in the aorta and are probably the secretions of the lateral B-cells. Granules of type NS-III are 40 to 120 nm and electron dense, and are intrinsic in origin. Similar granules occur in the intrinsic cells of the corpora cardiaca. E M studies have confirmed the rôle of the aorta as a neurohaemal organ for the medial neurosecretory cells, and the corpora cardiaca for the lateral neurosecretory cells of the brain. The corpora cardiaca also act as a reservoir for the intrinsic secretion. The corpus allatum is a solid body consisting of parenchymal cells with prominent nuclei, mitochondria, and endoplasmic reticulum. In between its cells are occasional glial cells and also neurosecretory as well as non-neurosecretory axons. The gland is devoid of A-cell NSM.     

Changes in weight of the pharyngeal gland and haemolymph titres of juvenile hormone,protein and vitellogenin in worker honey bees

Four physiological parameters (haemolymph-juvenile hormone titre, protein concentration, vitellogenin concentration, and pharyngeal gland dry weight) were examined in the following categories of queenright adult worker bees: summer bees 1–40 days old, winter bees 80–130 days old, 12–100-day old bees at the beginning of winter, 100–195-day old bees at the end of winter, and 1–100-day old bees experimentally induced to live longer in summer.In contrast to the continuously increasing titre of juvenile hormone in ageing summer bees, winter bees kept a constant low level. In bees at the beginning of winter, the hormone titre never reached high values. However, at the end of winter it rose from a low to a high level, comparable with the high titre of 24–40-day old summer bees. In experimentally induced longlived bees in summer, the juvenile hormone titre did not increase as in normal summer bees but remained low as in bees at the beginning of winter. Among the known natural juvenile hormones, only juvenile hormone III was present in the haemolymph of winter bees.The results support the hypothesis of polyphenism being regulated by the titre of juvenile hormone in the haemolymph.