A Rare Case of Hemolytic Disease of the Fetus and Newborn Caused by Anti-s Antibody in a Chinese Patient.

BACKGROUND: Anti-s is a rare alloantibody, and the reported cases of hemolytic disease of the fetus and newborn (HDFN) caused by anti-s are limited to non-Asian populations. METHODS: Here, we report the case of a Chinese woman with a history of multiple pregnancies who developed an alloantibody with anti-s specificity. RESULTS: Her newborn developed HDFN caused by anti-s but the clinical symptoms were not serious. After supportive treatment and bilirubin light phototherapy, the baby was discharged with a good prognosis. CONCLUSIONS: This is the first reported case of anti-s-induced HDFN in a Chinese patient, highlighting the need for further research in the Asian population.

A metabolomics study on the immunosuppressive effect of Tripterygium hypoglaucum (Levl.) Hutch in mice: The discovery of pathway differences in serum metabolites.

Tripterygium hypoglaucum (Levl.) Hutch (THH), a typical traditional Chinese medicine, is widely used in clinical practice for the treatment of rheumatoid arthritis, systemic lupus erythematous, and other connective tissue and autoimmune diseases. However, most related researches focused on the pharmacological effects of THH, while less attention has been paid to the immunosuppressive mechanism. The present study aims to determine the metabolic profiles, based on UPLC-Q-TOF-MS, identify differential metabolites, and find related metabolic pathways among the sensitization red blood cell (SRBC) model mice, THH treated mice, and cyclophosphamide treated group. Totally, 24 and 19 changed metabolites were found in the THH and cyclophosphamide treated groups respectively. Among them, we found that urocanate metabolic pathway change could be considered as the most relevant pathway associated with immunosuppression. This is the first study that comprehensively assessed the differences in metabolome between the model and THH treated groups. The results provide insights into the difference between the immunosuppressive mechanisms of THH and cyclophosphamide and also demonstrated that metabolomics is a valuable tool for investigating the efficacy of drugs in the treatment of diseases and the associated mechanism involved.

Design and preclinical characterization of ALXN1210: A novel anti-C5 antibody with extended duration of action.

Eculizumab, a monoclonal antibody (mAb) directed against complement protein C5, is considered to be the current standard of care for patients with paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic uremic syndrome. This study describes the generation and preclinical attributes of ALXN1210, a new long-acting anti-C5 mAb, obtained through select modifications to eculizumab to both largely abolish target-mediated drug disposition (TMDD) and increase recycling efficiency via the neonatal Fc receptor (FcRn). To attenuate the effect of TMDD on plasma terminal half-life (t1/2), histidine substitutions were engineered into the complementarity-determining regions of eculizumab to enhance the dissociation rate of the mAb:C5 complex in the acidic early endosome relative to the slightly basic pH of blood. Antibody variants with optimal pH-dependent binding to C5 exhibited little to no TMDD in mice in the presence of human C5. To further enhance the efficiency of FcRn-mediated recycling of the antibody, two additional substitutions were introduced to increase affinity for human FcRn. These substitutions yielded an additional doubling of the t½ of surrogate anti-mouse C5 antibodies with reduced TMDD in transgenic mice expressing the human FcRn. In conclusion, ALXN1210 is a promising new therapeutic candidate currently in clinical development for treatment of patients with PNH and atypical hemolytic uremic syndrome.

Anti-M induced severe haemolytic disease of foetus and newborn in a Malay woman with recurrent pregnancy loss.

Haemolytic disease of the foetus and newborn (HDFN) is caused by maternal red blood cells (RBC) alloimmunisation resulted from incompatibility of maternal and foetal RBCs. However, only a few HDFN attributed to anti-M were reported, varying from asymptomatic to severe anaemia with hydrops foetalis and even intrauterine death. A case of severe HDFN due to anti-M alloantibody from an alloimmunized grandmultiparous Malay woman with recurrent pregnancy loss is reported here. The newborn was delivered with severe and prolonged anaemia which required frequent RBC transfusions, intensive phototherapy and intravenous immunoglobulin administration. Although anti-M is rarely known to cause severe HDFN, a careful serological work-up and close assessment of foetal well-being is important, similar to the management of RhD HDFN. Alloimmunisation with anti-M type can lead to severe HDFN and even foetal loss.

Anti-Complementary Components of Helicteres angustifolia.

A first phenalenon derivative with an acetyl side chain at C-8, 8-acetyl-9-hydroxy-3-methoxy-7-methyl-1-phenalenon (compound 1), and a pair of new sesquilignan epimers at C-7″ of hedyotol C and hedyotol D analogs, hedyotol C 7″-O-ß-d-glucopyranoside (compound 2) and hedyotol D 7″-O-ß-d-glucopyranoside (compound 3) were isolated from the aerial parts of Helicteres angustifolia together with nine known compounds (4-12). Their structures were elucidated on the basis of spectroscopic methods, including mass spectroscopy, and 1D and 2D nuclear magnetic resonance. Eleven isolates exhibited anti-complementary activity. In particular, compounds 4 and 5 exhibited potent anti-complementary activities against the classical and alternative pathways with CH50 values of 0.040 ± 0.009 and 0.009 ± 0.002 mM, and AP50 values of 0.105 ± 0.015 and 0.021 ± 0.003 mM, respectively. The targets of compounds 4 and 5 in the complement activation cascade were also identified. In conclusion, the anti-complementary components of H. angustifolia possessed chemical diversity and consisted mostly of flavonoids and lignans in this study.

Methods for quantitative detection of antibody-induced complement activation on red blood cells.

Antibodies against red blood cells (RBCs) can lead to complement activation resulting in an accelerated clearance via complement receptors in the liver (extravascular hemolysis) or leading to intravascular lysis of RBCs. Alloantibodies (e.g. ABO) or autoantibodies to RBC antigens (as seen in autoimmune hemolytic anemia, AIHA) leading to complement activation are potentially harmful and can be - especially when leading to intravascular lysis - fatal(1). Currently, complement activation due to (auto)-antibodies on RBCs is assessed in vitro by using the Coombs test reflecting complement deposition on RBC or by a nonquantitative hemolytic assay reflecting RBC lysis(1-4). However, to assess the efficacy of complement inhibitors, it is mandatory to have quantitative techniques. Here we describe two such techniques. First, an assay to detect C3 and C4 deposition on red blood cells that is induced by antibodies in patient serum is presented. For this, FACS analysis is used with fluorescently labeled anti-C3 or anti-C4 antibodies. Next, a quantitative hemolytic assay is described. In this assay, complement-mediated hemolysis induced by patient serum is measured making use of spectrophotometric detection of the released hemoglobin. Both of these assays are very reproducible and quantitative, facilitating studies of antibody-induced complement activation.

Effects of Prunella vulgaris on the mice immune function.

The present study was designed to evaluate the effects of Prunella Vulgaris (P. vulgaris) on the immune function in mice. The mice were randomly divided into one control group and three treatment groups of 10 mice each. The control group received pure water and the treatment groups received P. vulgaris extract at concentrations of 0.15, 0.30 and 0.90 g/kg BW orally for 30 days, respectively. Changes in cell immune function, non-specific immunity and humoral immunity function were evaluated. Active lymphocytes and T lymphocyte subsets were determined by fluorescence-activated cell sorting (FACS). Certain Serum concentrations of cytokines were measured by enzyme-linked immunosorbent assay (ELISA). The results showed that, for cell immune function, compared with the control group, foot pad thickness in high dose group increased significantly (p<0.01), whereas no significant difference in the proliferative ability of splenic lymphocytes was observed among all groups (p>0.05). For non-specific immunity, NK cell activity increased significantly in a dose-dependent manner in P. vulgaris treated mice (p<0.01), mononuclear-macrophage function in medium and high dose P. vulgaris treated mice were significantly higher than that of the control group (p<0.05). For humoral immunity, no significant differences were observed in terms of the half value of hemolysis (HC50), number of hemolytic plaques and serum IgG level (p>0.05). The percentage of active T and Th lymphocytes of mice peripheral blood in high dose group were significantly higher than that of the control group (p<0.01). There was no significant difference in serum levels of IL-1ß, IL-4, IL-10 and IFN-γ among all of the four groups (p>0.05). The data indicated that 0.90 g/kg BW P. vulgaris extract (equivalent to 7.5 g/kg BW crude drug) had some effect on cellular immune function and non-specific immune function in mice.

Hemolytic disease of the newborn- anti c antibody induced hemolysis.

Hemolytic disease in the newborn, as a cause of early jaundice, is not uncommon. This is mostly due to Rh (D), ABO incompatibility and rarely due to other minor blood group incompatibility. The authors report two cases of Rh anti c isoimmunization presenting as significant early neonatal jaundice within the 20 h of life. Both the babies were treated with intensive phototherapy. One baby underwent exchange transfusion and the other required packed cell transfusion for anemia.

Anticomplement activity of organic solvent extracts from Korea local Amarantaceae spp.

The study evaluated the anticomplement activity from various solvent extracts of nine Amarantaceae plants (Achyranthes japonica (Miq.) Nakai, Amaranthus mangostanus L., Amaranthus retroflexus L., Amaranthus spinosus L., Celosia argentea var. spicata., Amaranthus lividus L., Celosia cristata L., Amaranthus viridis L., Gomphrena globosa L.) from South Korea on the classical pathway. We have evaluated various organic solvent extract from nine Amarantaceae plants with regard to its anticomplement activity on the classical pathway. Achyranthes japonica chloroform extracts showed inhibitory activity against complement system with 50% inhibitory concentrations (IC(50)) value of 73.1µg/ml. This is the first report of anticomplement activity from Amarantaceae plants.

Inhibitory effects of three oleanolic acid glycosides from Achyranthes japonica on the complement classical pathway.

The present study evaluated the anticomplement effects of isolated compounds from Achyranthes japonica in the classical pathway of the complement system. Using column chromatography, three compounds: achyranthoside C dimethyl ester, achyranthoside C butyl dimethyl ester, and achyranthoside E dimethyl ester were isolated and evaluated for in vitro anticomplement activity. Achyranthoside C dimethyl ester showed the most potent inhibitory activity against the complement system, with 50% inhibitory concentrations (IC(50)) values of 26.2 µg/mL. This is the first report of anticomplement activity of isolated compounds from A. japonica.

Inhibition effects of isolated compounds from Artemisia rubripes Nakai of the classical pathway on the complement system.

The study evaluated the anticomplement activity from isolated compounds from Artemisia rubripes Nakai from South Korea on the classical pathway. In the previous works, Artemisia rubripes chloroform extracts showed inhibitory activity against complement system. The chromatographic separation of a chloroform chloride extract of Artemisia rubripes led to the isolation of three compounds. Their structures were characterized to be scopoletin (1), 11,(13)-triene-6,12-olide (2), and 1ß,6α-dihydroxy-4(15)-eudesmene (3) by spectroscopic data. This is the first report of anticomplement activity of isolated compounds from Artemisia rubripes.

Isolated compounds from Sorghum bicolor L. inhibit the classical pathway of the complement.

The present study evaluated the anticomplement effects from isolated compounds of Sorghum bicolor in classical pathway complement system. Using column chromatograph, three compounds; Sorgoleone-362 (1), Sorgoleone-360 (2) and Sorgoleone-386 (3) were isolated and evaluated for in vitro anticomplement activity. Sorgoleone-386 showed inhibitory activity against complement system with 50% inhibitory concentrations (IC(50)) values of 148.3µg/ml. This is the first report of anticomplement activity of isolated compounds from Sorghum bicolor.

Anti-T haemolysins: the effects of sialic acid removal and 2-aminoethylisothiouronium bromide treatment of erythrocytes on immune lysis.

BACKGROUND AND OBJECTIVES: Intravascular haemolytic reactions are reported in red-cell T-activated patients after blood transfusion. The relationship between T antigen antibodies present in normal plasma and these reactions remains unclear. In this study, we assessed the haemolytic activity of T antibodies in vitro in comparison with anti-A/B antibodies. MATERIALS AND METHODS: We established a haemolysis assay based on treating target red-blood-cells (RBCs) with 2-aminoethylisothiouronium bromide (AET). Two hundred and seven blood donor sera were analysed for anti-T, anti-A/B haemolysins and anti-T agglutinins. RESULTS: Anti-T haemolysins were found in 4 (1·9%) blood donor sera using a standard haemolysis method and in 174 (84%) samples using AET-treated RBCs. Haemolysis correlated with agglutination titres (P<10(-7) ). With both methods, anti-T haemolysins were much weaker than anti-A and anti-B haemolysins. Gradual desialylation of RBCs showed a correlation between sialic acid level as indicated by agglutination with Sambucus nigra lectin and anti-T mediated haemolysis that was significantly increased (fold 2·4) independently of T antigen expression. CONCLUSION: These data indicate that, in vitro, anti-T-mediated haemolysis depends primarily on the degree of desialylation of target RBCs. They suggest that the haemolytic activity of T antibodies-containing human sera is usually weak and may only become significant in the very rare setting of a profound desialylation of RBCs.

Anti-complementary effect of polysaccharide B3-PS1 in Herba Scutellariae Barbatae (Scutellaria barbata).

The polysaccharide B3-PS1 was extracted and purified from Herba Scutellariae Barbatae (Scutellaria barbata D. Don), through bioactivity-guided fractionation. Average molecular weight of B3-PS1 was about 1,700,000 Da with a composition of Gal, Glc, Man and Ara in the ratio of 4.3:1.6:1.1:1.0, and trace of Rha, Fuc and Xyl. Preliminary data showed that 1) B3-PS1 inhibited complement activation of the classic pathway with CH(50) value of 0.12 +/- 0.02 mg/ml and of the alternative pathways with AP(50) value of 0.36 +/- 0.05 mg/ml; 2) B3-PS1 interacts with C1q, C1r, C1s, C2, C3, C4, C5 and C9 through a hemolytic assay. These results strongly suggested that B3-PS1 could be a potential candidate in treating those complement-associated diseases such as rheumatoid arthritis, Alzheimer's disease, and Adult Respiratory Distress Syndrome (ARDS).

Bovine colostrum contains immunoglobulin G antibodies against intimin, EspA, and EspB and inhibits hemolytic activity mediated by the type three secretion system of attaching and effacing Escherichia coli.

Enterohemorrhagic Escherichia coli (EHEC) is the main cause of hemolytic-uremic syndrome, an endemic disease in Argentina which had an incidence in 2005 of 13.9 cases per 100,000 children younger than 5 years old. Cattle appear to be a major reservoir of EHEC, and a serological response to EHEC antigens has been demonstrated in natural and experimental infections. In the current study, antibodies against proteins implicated in EHEC's ability to form attaching and effacing lesions, some of which are exported to the host cell via a type three secretion system (TTSS), were identified in bovine colostrum by Western blot analysis. Twenty-seven (77.0%) of the 35 samples examined contained immunoglobulin G (IgG) antibodies against the three proteins assayed in this study: EspA, EspB, and the carboxy-terminal 280 amino acids of gamma-intimin, an intimin subtype associated mainly with O157:H7 and O145:H- serotypes. Every colostrum sample was able to inhibit, in a range between 45.9 and 96.7%, the TTSS-mediated hemolytic activity of attaching and effacing E. coli. The inhibitory effect was partially mediated by IgG and lactoferrin. In conclusion, we found that early colostrum from cows contains antibodies, lactoferrin, and other unidentified substances that impair TTSS function in attaching and effacing E. coli strains. Bovine colostrum might act by reducing EHEC colonization in newborn calves and could be used as a prophylactic measure to protect non-breast-fed children against EHEC infection in an area of endemicity.

Complement consumption by Photobacterium damselae subsp. piscicida in seabream, red porgy and seabass normal and immune serum. Effect of the capsule on the bactericidal effect.

A virulent strain of Photobacterium damselae subsp. piscicida (Pdp) was grown without (C form) or with (C+ form) glucose supplementation, the latter to enhance capsule formation. Both forms were resistant to killing by normal serum of seabream, red porgy and seabass. However, the C form was killed by immune serum of all three fish species while the C+ form was killed only by seabream and red porgy sera and to a lesser extent than the C form. Both C and C+ forms consumed complement in normal serum and this consumption was enhanced by precoating the bacteria in specific fish antibody. Complement consumption was greatest in seabass serum, especially with antibody-coated C+ form yet in this case the bacteria were not killed. The killing of the C form in immune serum of all three fish species was completely inhibited by EGTA/Mg(2+), indicating that the mechanism of complement activation leading to killing of the bacteria was by the classical pathway. The results suggest that immune serum killing by the classical complement pathway may provide some degree of protection against pasteurellosis, but enhanced expression of the capsule by Pdp in vivo may restrict complement-mediated killing, especially in immunised seabass.

Characterization and immunostimulatory activity of an (1-->6)-a-D-glucan from the root of Ipomoea batatas.

The polysaccharide PSPP (purified sweet potato polysaccharide), isolated and purified from the roots of Ipomoea batatas, was found to be a glucan with a molecular weight of 53.2 kDa and specific rotation of +115.0 degrees (ca. 0.80, H(2)O). On the basis of methylation analysis, periodate oxidation, Smith degradation, infra-red spectroscopy, and (13)C NMR, the polysaccharide was confirmed as a (1-->6)-alpha-D-glucan. We evaluated the effects of polysaccharide PSPP on the in vivo immune function of mouse. Mice were treated with the polysaccharide PSPP (50, 150, and 250 mg/kg body weight) for 7 days. Phagocytic function, proliferation of lymphocytes, natural killer cell activity, hemolytic activity, and serum IgG concentration of the mice were studied. At the dose of 50 mg/kg, significant increments in proliferation of lymphocytes (P<0.05) and serum IgG concentration (P<0.05) were observed. At the dose of 150 and 250 mg/kg, significant increments (P<0.01 or P<0.05) were observed in all tested immunological indexes. A dose-dependent manner was demonstrated in phagocytic function, hemolytic activity, and serum IgG concentration, but not in proliferation of lymphocytes and natural killer cell activity. This suggests that PSPP improve the immune system and could be regarded as a biological response modifier.

The staphylococcal superantigen-like protein 7 binds IgA and complement C5 and inhibits IgA-Fc alpha RI binding and serum killing of bacteria.

The staphylococcal superantigen-like proteins (SSLs) are close relatives of the superantigens but are coded for by a separate gene cluster within a 19-kb region of the pathogenicity island SaPIn2. rSSL7 (formally known as SET1) bound with high affinity (K(D), 1.1 nM) to the monomeric form of human IgA1 and IgA2 plus serum IgA from primate, pig, rat, and horse. SSL7 also bound the secretory form of IgA found in milk from human, cow, and sheep, and inhibited IgA binding to cell surface FcalphaRI (CD89) and to a soluble form of the FcalphaRI protein. In addition to IgA, SSL7 bound complement factor C5 from human (K(D), 18 nM), primate, sheep, pig, and rabbit serum, and inhibited complement-mediated hemolysis and serum killing of a Gram-negative organism Escherichia coli. SSL7 is a superantigen-like protein secreted from Staphylococcus aureus that blocks IgA-FcR interactions and inhibits complement, leading to increased survival of a sensitive bacterium in blood.

Assessment of snapper (Pagrus auratus) natural IgM binding to bromelain treated sheep erythrocytes.

Normal snapper (Pagrus auratus Bloch and Schneider) serum was examined for natural IgM that binds to protease (bromelain) treated sheep erythrocytes (BrSRBC) in a model assay system that has been used to appraise natural IgM of various mammals. Normal snapper serum lysed BrSRBC while haemolysis was abrogated by heat inactivation of serum and in divalent cation-deficient conditions, indicative of classical complement mediated lysis. In addition, heat inactivated normal snapper serum agglutinated BrSRBC while phosphatidylcholine (PtC) liposomes partially inhibited both haemolysis and agglutination. Inhibition of haemolysis and agglutination may have been mediated by an interaction between immunoglobulin (Ig) and PtC as protein A purified snapper Ig bound to PtC liposomes. However it is not known if this binding was PtC specific nor if the binding was initiated by either the Fab and/or Fc domains of snapper Ig. BrSRBC plaque forming cells (PFC) were detected in the peritoneal cavity, spleen, head kidney and peripheral blood of normal snapper. The greatest proportion of BrSRBC PFC per B cell was within the peritoneal cavity followed by the spleen, peripheral blood and head kidney. Together, these data suggest that normal snapper serum may contain natural Ig that binds BrSRBC, activating the classical complement cascade.

Severe immune haemolysis after standard doses of Penicillin.

Summary Penicillin causes immune haemolytic anaemia by the 'drug-adsorption' mechanism and typically occurs after prolonged exposure to large doses of the drug. Withdrawal of the drug is associated with improved red cell survival and gradual cessation of haemolysis. Although this complication is uncommon, it can be potentially serious. An unusual case is described herein. The patient was exposed to a short course (9 days) of standard dose penicillin but suffered acute severe haemolysis about 1 week after cessation of therapy. A high titre anti-penicillin antibody (1 : 512) not cross-reacting with cephalosporins, was demonstrated. The delay in the development of immune haemolysis vis-à-vis penicillin therapy may be due to the patient being immunologically naive to the drug. Penicillin may persist for weeks in circulation, coating red cells and providing continued antigenic stimulation for the development of anti-penicillin antibody.