Mechanism of Metarhizium rileyi evading cellular immune responses in Helicoverpa armigera.

Upon entry into the hemocoel of host insects, entomopathogenic fungi switch to yeast-like hyphal bodies that are not recognized by host hemocytes and replicate extensively in the hemolymph. The mechanism by which hyphal bodies evade host cellular immunity is not well understood. This study compares Metarhizium rileyi conidia and hyphal bodies with respect to elicitation of the immune response of Helicoverpa armigera and recognition by host pattern recognition receptors (PRRs). We found that the ability of host hemocytes to phagocytize and nodulate hyphal bodies was weaker than those responses against conidia, suggesting that hyphal bodies are more able to evade host cellular immunity. Additionally, we found that the binding affinity of H. armigera ß-1,3-glucan recognition proteins was much lower for hyphal bodies than for conidia. We observed no agglutination response of H. armigera C-type lectin 3 (HaCTL3) against hyphal bodies, and HaCTL3 bound significantly less to hyphal bodies than to conidia, indicating that host PRRs have a lower affinity for hyphal bodies than for conidia. This study provides direct evidence that the mechanism whereby entomopathogenic fungi escape host cellular immunity involves the inability of host PRRs to sufficiently recognize hyphal bodies to elicit the cellular immune response.

Morphological and functional characterization of circulating hemocytes using microscopy techniques.

In the present study, Microscopy studies were performed to characterize the blood cells of the mangrove crab Episesarma tetragonum. Three types of hemocytes were observed: granulocytes, semi-granulocytes, and hyalinocytes or agranulocytes. Hyalinocytes have a distinguished nucleus surrounded by the cytoplasm, and a peculiar cell type was present throughout the cytosol, lysosomes with hemocyte types (granules) stained red (pink). Giemsa staining was used to differentiate between the large and small hemocytes. Ehrlich's staining was used to differentiate granule-containing cells in acidophils (55%), basophils (44%), and neutrophils (<1%). Periodic acid-Schiff staining was used to identify the sugar molecules in the cytoplasm. Cell-mediated immune reactions including phagocytosis, encapsulation, agglutination, and peroxidase-mediated cell adhesion are the functions of hemocytes. Agglutination reaction involves both kind of cells involved in yeast and heme-agglutination responses in invertebrates. The beta glucan outer layer of yeast cells was recognized by hemocyte receptors. Human RBC cells were agglutinated via granulocytes. E. tetragonum hemocytes are an important animal model for studying both ultrastructural and functional activity of circulating cells. In addition, E. tetragonum hemocytes exhibited excellent antibacterial and antibiofilm activities were studied through plating and microplate assays. Biofilm inhibition was also visualized through changes in biochemical assays and morphological variations were visualized through levels in in situ microscopy analysis.

Multivalent Affidendrons with High Affinity and Specificity toward Staphylococcus aureus as Versatile Tools for Modulating Multicellular Behaviors.

Multivalency is a widely occurring natural phenomenon often exploited in nanotechnology to enhance biorecognition. We report the preparation and characterization of versatile, multivalent Affitin-dendrimer conjugates (Affidendrons) showcased by a set targeting Staphylococcus aureus ( S. aureus), an opportunistic pathogen causing numerous hospital- and community-acquired infections. Affitins are small affinity proteins characterized by higher stability and lower cost-effective production than antibodies. The strategy presented provides a platform for the rational design of multivalent nanodevices that, retaining the ability of Affitins to recognize their target with high specificity, achieve a largely enhanced affinity. Affidendrons with precisely designed size and valency have been exploited to modulate complex multicellular behaviors of S. aureus, such as agglutination and biofilm formation. Agglutination assays showed that Affidendrons rapidly cross-link S. aureus strains with high bacterial cell selectivity. Moreover, remarkably low concentrations of Affidendrons were able to effectively prevent biofilm formation. Overall, Affidendrons represent a promising platform for the rapid and selective pathogen identification, infection imaging, and theranostic applications.

Antimicrobial properties and phenoloxidase activation of the lectin isolated from kadal shrimp (Metapenaeus dobsoni).

The present study reveals purification and characterization of the lectin from the haemolymph of Metapenaeus dobsoni. The Md-Lec was purified by affinity chromatography with mannose coupled sepharose CL-4B column and it exhibits single band with a molecular weight of 68 kDa in SDS-PAGE. Furthermore, the molecular mass was confirmed by MALDI-TOF and functional groups present were analysed by FTIR. The surface morphology of purified Md-Lec displays the homogeneous nature of protein. The X-ray diffraction (XRD) analysis expresses three peaks at 10.7716̊, 21.6258̊ and 31.7523̊which indicate the crystalline nature of the protein and the retention time of 3.068 min evident from HPLC reveals the purity of the sample. Functional analysis of purified Md-Lec exhibits yeast agglutination activity against Saccharomyces cerevisiae and has the ability to agglutinate the human erythrocytes, which was observed by light microscopy. It also exhibited phenoloxidase activation, encapsulation and phagocytic activities. In addition, purified Md-Lec showed the broad spectrum of bacterial agglutination activity against Gram negative Vibrio parahaemolyticus and Aeromonas hydrophila, important fish pathogens. Antiviral potential and anticancer activity of purified Md-Lec against CyHV-2 virus and MDA-MB-231 breast cancer cell lines were also evaluated in this study.

Increased biofilm formation ability in Klebsiella pneumoniae after short-term exposure to a simulated microgravity environment.

Biofilm formation is closely related to the pathogenetic processes of Klebsiella pneumoniae, which frequently causes infections in immunocompromised individuals. The immune system of astronauts is compromised in spaceflight. Accordingly, K. pneumoniae, which used to be isolated from orbiting spacecraft and astronauts, poses potential threats to the health of astronauts and mission security. Microgravity is a key environmental cue during spaceflight. Therefore, determining its effects on bacterial biofilm formation is necessary. In this study, K. pneumoniae ATCC BAA-1705 was exposed to a simulated microgravity (SMG) environment. K. pneumoniae grown under SMG formed thicker biofilms compared with those under normal gravity (NG) control after 2 weeks of subculture. Two indicative dyes (i.e., Congo red and calcofluor) specifically binding to cellulose fibers and/or fimbriae were utilized to reconfirm the enhanced biofilm formation ability of K. pneumoniae grown under SMG. Further analysis showed that the biofilms formed by SMG-treated K. pneumoniae were susceptible to cellulase digestion. Yeast cells mannose-resistant agglutination by K. pneumoniae type 3 fimbriae was more obvious in the SMG group, which suggests that cellulose production and type 3 fimbriae expression in K. pneumoniae were both enhanced under the SMG condition. Transcriptomic analysis showed that 171 genes belonging to 15 functional categories were dysregulated in this organism exposed to the SMG conditions compared with those in the NG group, where the genes responsible for the type 3 fimbriae (mrkABCDF) and its regulator (mrkH) were upregulated.

Sperm conjugation in mammal reproductive function: Different names for the same phenomenon?

In many mammalian and non-mammalian species, mature sperm interact within the female reproductive tract or inside the epididymal lumen using cohesive forces. This phenomenon, known as "sperm conjugation," is sometimes confused with sperm agglutination, which is the result of the interaction of epididymal or ejaculate spermatozoa upon release into culture medium. In addition to "agglutination," the terms "association," "rouleaux," or "rosettes" are employed interchangeably to describe the conjugation phenomenon, which inevitably causes confusion due to the non-unifying nomenclature. This variety of descriptions is likely due to a poor understanding of the molecular mechanisms involved in such conspicuous cell-cell interaction as well as the different morphologies that result from such interactions among species. Here, we summarize the published data regarding mammalian sperm conjugation, considering the organisms in which sperm interaction was observed; the particular terminology employed; findings regarding the components that enable sperm to adhere; sperm behavior when deposited in the female reproductive tract; and hypotheses formulated to clarify the biological function and, when known, the mechanisms for sperm interaction. We also propose a new classification system for this phenomenon that might clearly unify the criteria used to describe this behavior. Mol. Reprod. Dev. 83: 884-896, 2016 © 2016 Wiley Periodicals, Inc.

Modeling of Virion Collisions in Cervicovaginal Mucus Reveals Limits on Agglutination as the Protective Mechanism of Secretory Immunoglobulin A.

Secretory immunoglobulin A (sIgA), a dimeric antibody found in high quantities in the gastrointestinal mucosa, is broadly associated with mucosal immune protection. A distinguishing feature of sIgA is its ability to crosslink pathogens, thereby creating pathogen/sIgA aggregates that are too large to traverse the dense matrix of mucin fibers in mucus layers overlying epithelial cells and consequently reducing infectivity. Here, we use modeling to investigate this mechanism of "immune exclusion" based on sIgA-mediated agglutination, in particular the potential use of sIgA to agglutinate HIV in cervicovaginal mucus (CVM) and prevent HIV transmission. Utilizing reported data on HIV diffusion in CVM and semen, we simulate HIV collision kinetics in physiologically-thick mucus layers-a necessary first step for sIgA-induced aggregation. We find that even at the median HIV load in semen of acutely infected individuals possessing high viral titers, over 99% of HIV virions will penetrate CVM and reach the vaginal epithelium without colliding with another virion. These findings imply that agglutination is unlikely to be the dominant mechanism of sIgA-mediated protection against HIV or other sexually transmitted pathogens. Rather, we surmise that agglutination is most effective against pathogens either present at exceedingly high concentrations or that possess motility mechanisms other than Brownian diffusion that significantly enhance encounter rates.

[The mechanism of change in speed of agglutination of human erythrocytes under the influence of adrenaline].

In the study of red blood cells of 80 men found that adrenaline (10(-10) - 10(-6) g/mL) and phenylephrine (10-(10) - 10(-6) g/mL) dose-dependently increase the speed of agglutination of red blood cells, according to the decrease in agglutination of the start time and ginipral (10(-10) - 10(-7) g/mL), on the contrary, decreases it. The effect of adrenaline and phenylephrine is blocked by nicergoline (10(-6) g/mL), increased obzidan (10(-6) g/mL) and does not change under the action ofyohimbine (10(-6) g/mL) and atenolol (10(-6) g/mL). These data indicate that the speed of agglutination increases with activation alpha1-adrenergic receptor (AR) and decreases in the activation of beta2-AR, while the activation of alpha2- and beta1-AR does not affect it. Trifluoperazine (10(-6) g/mL) as the calmodulin antagonist, barium chloride (10(-6) g/mL) as a blocked of Ca(2+)-dependent K(+)-channels and indomethacine (10(-6) g/mL) as an inhibitor of cyclooxygenase and phospholipase A2 inhibit the ability of adrenaline to increases the speed of agglutination of red blood cells. This suggests that the effect of adrenaline caused an increase in erythrocyte entry of Ca2+, activation of calmodulin, cyclooxygenase, phospholipase A2 and the release of K+ from red blood cell through the Ca(2+)-dependent K+ channels, which is regarded as a manifestation of eryptosis. Indirectly, this means that more efficient activation of alpha1-AR and beta2-AR, respectively, increases or, conversely, decreases the rate of eryptosis.

Helicobacter pylori TlyA agglutinates liposomes and induces fusion and permeabilization of the liposome membranes.

Helicobacter pylori TlyA is a pore-forming hemolysin with potent cytotoxic activity. To explore the potential membrane-damaging activity of H. pylori TlyA, we have studied its interaction with the synthetic liposome vesicles. In our study, H. pylori TlyA shows a prominent ability to associate with the liposome vesicles without displaying an obligatory requirement for any protein receptor on the liposome membranes. Interaction of TlyA triggers agglutination of the liposome vesicles. Such agglutinating activity of TlyA could also be observed with erythrocytes before the induction of its pore-forming hemolytic activity. In addition to its agglutinating activity against liposomes, TlyA also induces fusion and disruption of the liposome membranes. Altogether, our study highlights novel membrane-damaging properties of H. pylori TlyA that have not been documented previously with any other TlyA family protein.

A critical role for the regulation of Syk from agglutination to aggregation in human platelets.

Agglucetin, a tetrameric glycoprotein (GP) Ibα agonist from Formosan Agkistrodon acutus venom, has been characterized as an agglutination inducer in human washed platelets (WPs). In platelet-rich plasma (PRP), agglucetin dramatically elicits a biphasic response of agglutination and subsequent aggregation. For clarifying the intracellular signaling events from agglutination to aggregation in human platelets, we examined the essential signaling molecules involved through the detection of protein tyrosine phosphorylation (PTP). In WPs, an anti-GPIbα monoclonal antibody (mAb) AP1, but not a Src kinase inhibitor PP1, completely inhibited agglucetin-induced agglutination. However, PP1 but not AP1 had a potent suppression on platelet aggregation by a GPVI activator convulxin. The PTP analyses showed agglucetin alone can cause a weak pattern involving sequential phosphorylation of Lyn/Fyn, Syk, SLP-76 and phospholipase Cγ2 (PLCγ2). Furthermore, a Syk-selective kinase inhibitor, piceatannol, significantly suppressed the aggregating response in agglucetin-activated PRP. Analyzed by flow cytometry, the binding capacity of fluorophore-conjugated PAC-1, a mAb recognizing activated integrin αIIbß3, was shown to increase in agglucetin-stimulated platelets. Again, piceatannol but not PP1 had a concentration-dependent suppression on agglucetin-induced αIIbß3 exposure. Moreover, the formation of signalosome, including Syk, SLP-76, VAV, adhesion and degranulation promoting adapter protein (ADAP) and PLCγ2, are required for platelet aggregation in agglucetin/fibrinogen-activated platelets. In addition, GPIbα-ligation via agglucetin can substantially promote the interactions between αIIbß3 and fibrinogen. Therefore, the signal pathway of Lyn/Fyn/Syk/SLP-76/ADAP/VAV/PLCγ2/PKC is sufficient to trigger platelet aggregation in agglucetin/fibrinogen-pretreated platelets. Importantly, Syk may function as a major regulator for the response from GPIbα-initiated agglutination to integrin αIIbß3-dependent aggregation in human platelets.

Measurement of RBC agglutination with microscopic cell image analysis in a microchannel chip.

Since Landsteiner's discovery of ABO blood groups, RBC agglutination has been one of the most important immunohematologic techniques for ABO and RhD blood groupings. The conventional RBC agglutination grading system for RhD blood typings relies on macroscopic reading, followed by the assignment of a grade ranging from (-) to (4+) to the degree of red blood cells clumping. However, with the new scoring method introduced in this report, microscopically captured cell images of agglutinated RBCs, placed in a microchannel chip, are used for analysis. Indeed, the cell images' pixel number first allows the differentiation of agglutinated and non-agglutinated red blood cells. Finally, the ratio of agglutinated RBCs per total RBC counts (CRAT) from 90 captured images is then calculated. During the trial, it was observed that the agglutinated group's CRAT was significantly higher (3.77-0.003) than that of the normal control (0). Based on these facts, it was established that the microchannel method was more suitable for the discrimination between agglutinated RBCs and non-agglutinated RhD negative, and thus more reliable for the grading of RBCs agglutination than the conventional method.

Can salivary activity predict periodontal breakdown in A. actinomycetemcomitans infected adolescents?

OBJECTIVE: While Aggregatibacter actinomycetemcomitans (Aa) is highly associated with localised aggressive periodontitis (LAP) many Aa-carriers do not develop LAP. This study was designed to determine whether specific salivary factors could distinguish between subjects who have Aa initially and remain healthy (H/AA) as compared to those who develop LAP (LAP/AA). DESIGN: H/AA subjects and healthy controls with no Aa (H) were enrolled in a longitudinal cohort study to investigate initiation of bone loss (LAP) over 3 years. After detection of LAP, stored saliva from 10 H, 10 H/AA, and 10 LAP/AA subjects was thawed, processed, and tested for (1) lactoferrin (Lf) concentration and iron levels; (2) agglutination of Aa; (3) killing of Gram-positive bacteria. RESULTS: LAP/AA saliva levels of Lf iron were low prior to and after bone loss (3.6+1.7ngFe/µg) (LAP/AA vs. H and H/AA p≤0.01). Saliva from H/AA subjects caused Aa to agglutinate significantly more than H or LAP/AA saliva (p≤0.01). LAP/AA saliva killed Streptococcus mutans, Streptococcus sanguis and Lactobacillus in vitro by >83%. Saliva from H individuals killed these bacteria by <3.3% (LAP/AA vs. H; p≤0.01). H/AA killing was intermediate. CONCLUSION: LAP/AA saliva showed: low levels of Lf iron, minimal Aa agglutinating activity, and high killing activity against Gram-positive bacteria. Aa-positive healthy saliva (H/AA) showed: higher levels of Lf iron, maximal Aa agglutinating activity, and moderate killing of Gram-positive bacteria. A salivary activity profile can distinguish between subjects who are Aa-positive and remain healthy from those who develop LAP.

Evidence for a novel biological role for the multifunctional ß-1,3-glucan binding protein in shrimp.

ß-1,3-Glucan binding proteins (ßGBPs) are soluble pattern recognition proteins/receptors that bind to ß-1,3-glucans from fungi cell walls. In crustaceans, ßGBPs are abundant plasmatic proteins produced by the hepatopancreas, and have been proved to play multiple biological functions. Here, we purified and characterized novel members of the ßGBP family from the hemolymph of two Brazilian shrimps, Farfantepenaeus paulensis (FpßGBP) and Litopenaeus schmitti (LsßGBP). As observed for other crustacean species, FpßGBP and LsßGBP are monomeric proteins (∼100kDa) able to enhance the activation of the prophenoloxidase system, a potent antimicrobial defense conserved in arthropods. More interestingly, we provided here evidence for a novel biological activity for shrimp ßGBPs: the agglutination of fungal cells. Finally, we investigated the modulation of the ßGBP gene in F. paulensis shrimps experimentally infected with a cognate fungal pathogen, Fusarium solani. From our expression data, ßGBP gene is constitutively expressed in hepatopancreas and not modulated upon a non-lethal fungal infection. Herein, we have improved our knowledge about the ßGBP family by the characterization of a novel biological role for this multifunctional protein in shrimp.

Mapping key interactions in the dimerization process of HBHA from Mycobacterium tuberculosis, insights into bacterial agglutination.

HBHA is a cell-surface protein implicated in the dissemination of Mycobacterium tuberculosis (Mtb) from the site of primary infection. Its N-terminal coiled-coil region is also involved in bacterial agglutination. However, despite the importance of HBHA dimerization in agglutination, protein regions involved in dimerization are hitherto not known. Here, we mapped these regions by coupling peptide synthesis, biochemical and computational analyses, and identified structural determinants for HBHA monomer-monomer recognition. Importantly, we obtained the first molecule able to induce HBHA dimer disaggregation at 37°C, the typical growth temperature of Mtb. This result provides new opportunities towards the development of Mtb anti-aggregation molecules with therapeutic interest.

Role of zebrafish thrombocyte and non-thrombocyte microparticles in hemostasis.

Hemostasis is a defense mechanism that protects an organism from bleeding in the event of injury. We have previously demonstrated the utility of the zebrafish as a model to study human hemostasis. However, there are no studies on the role of microparticles in hemostasis in early vertebrates. Studying microparticles in zebrafish may provide insight into the evolution of microparticle function in hemostasis and may lead to direct observation of these microparticles in zebrafish larvae due to transparency of the vessels. In this investigation we demonstrate the presence of cellular microparticles in fish blood by both immunostaining as well as by using zebrafish whose thrombocytes are labeled with green fluorescent protein. Further investigation showed that microparticles were also labeled by fluorescein isothiocyanate annexin V, suggesting that these particles are derived via apoptosis. A portion of the fluorescein isothiocyanate annexin V labeled microparticles was also labeled by DiI-C18. Labeling by DiI-C18 suggests that some microparticles are derived from young thrombocytes. Additionally, GpIIb antibody labels almost all thrombocyte-derived microparticles and a greater percentage of microparticles are labeled by GpIIb antibody than by DiI-C18. This suggests that thrombocyte microparticles are derived from both young and mature thrombocytes. Furthermore, the increase of microparticles by adding excessive microparticles into blood in vitro and through intravenous injections led to an increased hemostatic response. In addition, treatment with tumor necrosis factor alpha resulted in an increased number of thrombocyte microparticles and enhanced hemostasis; in contrast, treatment with zVAD-FMK, a caspase inhibitor, resulted in a decrease in thrombocyte microparticles and decreased hemostasis. We also found that thrombocyte microparticles agglutinate, along with other cells and cellular microparticles, in the presence of an excess of either ristocetin or ultra-large von Willebrand factor. Also, stimulation of von Willebrand factor release in vivo resulted in clusters of thrombocyte microparticles in the veins. Moreover, thrombocyte microparticles were the first to appear at the site of arterial injury. We found that thrombocyte microparticles are functionally equivalent to platelet microparticles. The microparticles initiate arterial thrombus formation in a von Willebrand factor-dependent manner and further enhance thrombus formation by forming clusters of microparticles in venous thrombosis. This finding may have applications for understanding the role of platelet microparticles in humans and may have diagnostic applications.

Preventing Staphylococcus aureus sepsis through the inhibition of its agglutination in blood.

Staphylococcus aureus infection is a frequent cause of sepsis in humans, a disease associated with high mortality and without specific intervention. When suspended in human or animal plasma, staphylococci are known to agglutinate, however the bacterial factors responsible for agglutination and their possible contribution to disease pathogenesis have not yet been revealed. Using a mouse model for S. aureus sepsis, we report here that staphylococcal agglutination in blood was associated with a lethal outcome of this disease. Three secreted products of staphylococci--coagulase (Coa), von Willebrand factor binding protein (vWbp) and clumping factor (ClfA)--were required for agglutination. Coa and vWbp activate prothrombin to cleave fibrinogen, whereas ClfA allowed staphylococci to associate with the resulting fibrin cables. All three virulence genes promoted the formation of thromboembolic lesions in heart tissues. S. aureus agglutination could be disrupted and the lethal outcome of sepsis could be prevented by combining dabigatran-etexilate treatment, which blocked Coa and vWbp activity, with antibodies specific for ClfA. Together these results suggest that the combined administration of direct thrombin inhibitors and ClfA-antibodies that block S. aureus agglutination with fibrin may be useful for the prevention of staphylococcal sepsis in humans.

Identification and agglutination properties of hemocyanin from the mud crab (Scylla serrata).

Infectious diseases have significantly delayed the growth of crab aquaculture. Identification of the immune molecules and characterization of the defense mechanisms will be pivotal to the reduction of these diseases. Hemocyanin is an important non-specific immune protein present in the hemolymph of both mollusks and arthropods. However, little is known about the hemocyanin from the mud crab Scylla serrata. In this study, we identified the S. serrata hemocyanin using affinity proteomics and investigated its agglutinative properties. The results showed that S. serrata hemocyanin consists of five subunits with molecular weights of 70, 72, 75, 76 and 80 kDa, respectively. It demonstrated agglutination activities against seven bacterial species at concentrations ranging from 7.5 to 30 µg/ml. Agglutination was inhibited by 50-200 mM of N-acetylneuraminic acid, α-d-glucose, d-galactose and d-xylose. The 76 kDa subunit was identified as the protein that primarily binds bacterial cells and we speculate that it functions as the agglutinating subunit. We showed that outer membrane proteins (Omp) of bacteria could completely inhibit agglutination and that the agglutination activities of hemocyanin against Escherichia coli ▵OmpA and ▵OmpX mutants were significantly decreased, suggesting that these two Omps may be important ligands of hemocyanin. Together, the data collectively suggests that the 76 kDa subunit of S. serrata hemocyanin mediates agglutination through recognition of OmpA and OmpX proteins in bacteria.

CfLGBP, a pattern recognition receptor in Chlamys farreri involved in the immune response against various bacteria.

Lipopolysaccharide and beta-1, 3-glucan binding protein (LGBP) is a kind of pattern recognition receptor, which can recognize and bind LPS and beta-1, 3-glucan, and plays curial roles in the innate immune defense against Gram-negative bacteria and fungi. In this study, the functions of LGBP from Zhikong scallop Chlamys farreri performed in innate immunity were analyzed. Firstly, the mRNA expression of CfLGBP in hemocytes toward three typical PAMPS stimulation was examined by realtime PCR. It was up-regulated extremely (P < 0.01) post stimulation of LPS and beta-glucan, and also exhibited a moderate up-regulation (P < 0.01) after PGN injection. Further PAMPs binding assay with the polyclonal antibody specific for CfLGBP proved that the recombinant CfLGBP (designated as rCfLGBP) could bind not only LPS and beta-glucan, but also PGN in vitro. More importantly, rCfLGBP exhibited obvious agglutination activity towards Gram-negative bacteria Escherichia coli, Gram-positive bacteria Bacillus subtilis and fungi Pichia pastoris. Taking the results of immunofluorescence assay into account, which displayed CfLGBP was expressed specifically in the immune cells (hemocytes) and vulnerable organ (gill and mantle), we believed that LGBP in C. farreri, serving as a multi-functional PRR, not only involved in the immune response against Gram-negative and fungi as LGBP in other invertebrates, but also played significant role in the event of anti-Gram-positive bacteria infection. As the first functional research of LGBP in mollusks, our study provided new implication into the innate immune defense mechanisms of C. farreri and mollusks.

Estudio de anticuerpos de inmunización ABO en niños con ascariosis / Study of ABO immune antibodies in children with ascariasis

Los anticuerpos inmunes tienen una gran importancia clínica, pues pueden producir reacción hemolítica o enfermedad hemolítica del recién nacido. El objetivo de este trabajo era detectar anticuerpos de inmunización ABO en niños con ascariosis. Se trabajó con muestras de suero obtenidas de una población de niños con ascariosis y de otra población control de niños sanos. Se determinó el grupo ABO en los sueros y se registró si el niño había recibido tratamiento antiparasitario en el momento de la extracción de la muestra. El estudio de los anticuerpos anti-Ay anti-B comprendió: prueba de hemólisis cualitativa, tiempo hemolítico medio, aglutinación y titulación en medio salino y enzimático, titulación en medio enzimático antes y después del tratamiento con 2-mercaptoetanol, y estudio de amplitud térmica. Se realizó también la inhibición con agarosa para los anti-B. El estudio de los anticuerpos ABO en la población de niños parasitados demostró que el 52,63% de los anti-A y el 31,03%de los anti-B tenían características de anticuerpos inmunes. No se encontró ningún anticuerpo ABO inmune en la población control. Se comprobó la existencia de 6 anticuerpos antigalactosa de clase IgG en el grupo de niños parasitados. Todos los sueros con anticuerpos inmunes fueron obtenidos antes o durante el tratamiento específico. La ausencia de anticuerpos de inmunización en los niños que concluyeron el tratamiento y en los niños de la población control sugeriría que la ascariosis es el estímulo externo para su aparición. El seguimiento de los anticuerpos inmunes sería útil para evaluar la evolución de la infección después del tratamiento (AU)

Immune antibodies are of clinical importance because they can produce a hemolytic reaction or hemolytic disease of the newborn. The aim of this study was to detect ABO immune antibodies in children with ascariasis. Serum samples were collected from a population of children with ascariasis and from a control population of healthy children. The ABO group was determined in the sera, and it was recorded if the child had received antiparasitic treatment at the time of the sample collection. The study of anti-A and anti-B antibodies involved a qualitative hemolysis test, mean hemolysis time, agglutination and titration in a saline medium and an enzyme medium, titration before and after 2- mercaptoethanol treatment in an enzyme medium, and a thermal amplitude test. An inhibition test for anti-B antibodies was also carried out in agarose. The study of ABO antibodies in the population of children with parasitemia showed that 52.63% of the anti-A and 31.03%of the anti-B antibodies had characteristics of immune antibodies. No ABO immune antibodies were found in the control population. The presence of 6 anti-galactose antibodies was demonstrated in the group with ascariasis. All the sera with immune antibodies were collected before or during the specific treatment. The absence of immune antibodies in the children that completed the treatment and in the children of the control population would suggest that ascariasis was the external stimulus for their development. The monitoring of these antibodies would be useful for the evaluation of the course of the infection following treatment (AU)