Agglutinating Antibodies Research Articles

Proportion of Rh phenotypes in voluntary blood donors

BackgroundThe Rh system is the major blood group system besides ABO system. Even after proper blood grouping and cross matching there is a possibility of alloimmunization and antibody production in the recipients against the Rh or minor blood group antigens like Kell, MNSs, Duffy etc. Keeping in view the heavy financial burden of complete phenotyping of blood; the determination of only Rh phenotypes can play a major role in preventing alloimmunization and adverse events in multitransfusion cases. To determine the proportion of Rh phenotypes in voluntary blood donors with a view to generate blood bank data for constitution of panel of blood donors for multipurpose utilities. MethodIdentification of Rhesus factors (Rh) was done by the antigen antibody agglutination test by the test tube method on 10,133 healthy voluntary donors. ResultsThe phenotypic frequencies of Rh blood groups in the studied population were D-92.25%, C-87.55%, E-26.55%, c-51.06% and e-98.42%. Thus ‘e’ was the most common and E was the least common of all the Rh types. Phenotypically DCCee group was the most common phenotype and dccee was least common type. ConclusionDetermination of Rh phenotypes can play a major role in preventing alloimmunization and avoiding adverse events in multitransfusion cases.

The efficacy of three mycotoxin adsorbents to alleviate aflatoxin B1-induced toxicity in Oreochromis niloticus

Aflatoxicosis, toxicity of aflatoxin, is of great concern in aquaculture. This study was conducted to assess the efficacies of three adsorbents, a hydrated sodium calcium aluminosilicates (HSCAS), Saccharomyces cerevisiae (S.C.) and an esterified glucomannan (EGM), against feed contaminated with contained 200 μg/kg (ppb) aflatoxin B1 (AFB1). A total of 240 Nile tilapia fingerlings, Oreochromis niloticus (15 ± 2 g), were randomly divided into eight experimental groups (30 fish per group) with three replicates. Group T1 represented the negative control fed on a basal diet, and T2 was the positive control group fed on a basal diet supplemented with 200 ppb AFB1. Groups T3, T4 and T5 were fed the AFB1-contaminated diet (200 ppb) supplemented with 0.5 % HSCAS, 0.25 % S.C or 0.25 % EGM, respectively. Groups T6, T7 and T8 were fed a basal diet supplemented with 0.5 % HSCAS, 0.25 % S.C or 0.25 % EGM, respectively. The reduction in AFB1-bioavailability was judged by toxin residues in fish musculature throughout the study beginning at the second week of exposure. AFB1 reduced the survivability, total weight gain, average daily gain and specific growth rate, evident as early as the second week of exposure. The total erythrocyte count, hemoglobin content and total leukocyte count were significantly decreased after AFB1 exposure for 6, 8 and 10 weeks, respectively. Prolonged administration of AFB1 led to significant increases in serum alanine transaminase, aspartate transaminase and creatinine activity, and produced significant decreases in plasma proteins, including serum globulin. The specific immune response was assessed by an agglutinating antibody titer after immunization of the fish with an Aeromonas hydrophila vaccine. The antibody titer and relative level of protection of fish challenged with Aeromonas hydrophila were reduced throughout the period of examination in AFB1-exposed fish. Supplementation with HSCAS, S.C. or EGM significantly improved growth performance, blood parameters and immune status; in addition, these groups showed decreased AFB1 residues in fish musculature when compared with AFB1-treated fish. HSCAS effectively reduced AFB1 toxicity, whereas S.C. and EGM were less efficacious.

Effects of dietary isoleucine on the immune response, antioxidant status and gene expression in the head kidney of juvenile Jian carp (Cyprinus carpio var. Jian)

This study was conducted to evaluate the effects of dietary isoleucine (Ile) on the immune response, antioxidant status and gene expression in the head kidney of juvenile Jian carp (Cyprinus carpio var. Jian). Six semi-purified isonitrogenous diets (4.2, 7.0, 9.5, 11.9, 13.9 and 16.9 g Ile kg−1 diet) were fed to Jian carp (6.9 ± 0.03 g) for 60 days. The results showed that Ile supplementation improved the head kidney index, red and white blood cell counts, anti-hydroxyl radical capacity and the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione-S-transferase (P < 0.05), and decreased the malondialdehyde, protein carbonyl and glutathione contents in the head kidney (P < 0.05). After a 60 day feeding trial, an Aeromonas hydrophila challenge study was conducted for 17 days. Differences in survival rate, leucocyte phagocytic activity, serum lysozyme activity, acid phosphatase activity, haemagglutination titre, complement components 3 and 4, immunoglobulin M level and A. hydrophila agglutination antibody titre followed the same trend as that of the head kidney index (P < 0.05). Furthermore, real time polymerase chain reaction revealed that relative mRNA expression of transforming growth factor β2 and target of rapamycin (TOR) in the head kidney significantly increased with increasing Ile levels (P < 0.05). Conversely, the relative mRNA expression of tumour necrosis factor α, interleukin 10 and eIF4E-binding protein (4E-BP) in the head kidney showed a downward trend (P < 0.05). Collectively, this study indicates that dietary Ile improves the fish immune response, regulates the antioxidant status and cytokine, TOR and 4E-BP gene expression in the head kidney.

Effect of a monovalent vaccine against Leptospira borgpetersenii serovar Hardjo strain hardjobovis on fertility in Holstein dairy cattle

To determine whether vaccination with a monovalent vaccine against Leptospira borgpetersenii serovar Hardjo strain hardjobovis would improve reproductive efficiency in Holstein cattle in a commercial dairy setting. Randomized controlled trial. 1,894 Holstein cows and heifers from a Central California dairy. Cattle were assigned to undergo SC administration of a monovalent vaccine against Leptospira borgpetersenii serovar Hardjo strain hardjobovis (n = 986) or a placebo (lactated Ringer's solution; 908). At the end of their lactation period, cows received 2 doses of the vaccine or placebo, 28 to 35 days apart, with the initial dose administered in conjunction with oxytetracycline. Heifers received the same treatments, with the second dose administered at least 2 weeks before their entrance into the heifer breeding pen. Urine and blood samples were collected from randomly selected cattle immediately before and 1 year after the trial began and submitted for fluorescent antibody and microscopic agglutination testing to identify any infecting Leptospira serovar. The initial herd prevalence of active infection with strain hardjobovis was 13% (6/46 tested cattle), followed by 15% (6/40) 1 year after the trial began. The odds of heifers conceiving over the period at risk for conception, regardless of vaccination, was approximately 2.8 times as high as for primiparous and pluriparous cows. Survival analysis of days from parturition to conception revealed that the vaccine protocol had no effect on the probability of conception between the vaccinated and control groups. The vaccine protocol had no impact on pregnancy loss. The evaluated vaccination protocol against Leptospira strain hardjobovis was not effective in improving reproductive efficiency in commercial Holstein dairy cows or in decreasing urine shedding of leptospires.

Current Trends and Investigative Developments in Celiac Disease

Celiac disease has become extensively studied. What could be the cause? Increasing the accuracy of diagnostic tests for celiac disease has led to more discovered cases. Serological diagnosis of celiac disease has undergone important changes in recent years. Application of serological tests has reflected the diagnostic performance of tissue transglutaminase antibody and endomysial antibody as screening tests for celiac disease but also the progress of new serological tests as the antibodies against synthetic deamidated gliadin peptides. Serological tests are largely responsible for the recognition that celiac disease is not a rare disease. The Consensus in celiac disease from 2008 conducted under the aegis of the European Society of Pediatric Gastroenterology, Hepatology and Nutrition jointly with North American Society of Pediatric Gastroenterology, Hepatology and Nutrition which agreed that “Celiac disease is an immune-mediated enteropathy that can affect any system or organ and that can present itself with a wide range of clinical manifestations of variable severity” was confirmed. But increasing prevalence of this disease has led to the need for new methods of treatment among patients with celiac disease. Studies on quality of life of patients with celiac disease have questioned the gluten-free diet. As such new therapies, like TG2 inhibitors, the copolymer P (HEMA-co-SS) and other new experimental therapies, have emerged in celiac disease. The new therapies in celiac disease are based on new investigations in gluten toxicity screening, like K562(S)-cell agglutination, A1 and G12 monoclonal antibodies and proteomics. In this paper we want to present the investigative developments in celiac disease. We also want to find whether a new treatment in celiac disease is necessary.

Development and plasticity of innate immune function in altricial house sparrow nestlings

Ontogeny of immune function in altricial birds has been understudied. We examined development of the innate immune system in free‐living house sparrows and the flexibility of innate immune response to food restriction (FR) and refeeding in captive house sparrows. Ecological immunology techniques were used to examine components of the innate immune system. Natural antibody agglutination and complement‐mediated lysis increased with age, yet levels in near‐fledgling birds were about 50% lower than in hatch‐year birds and adults. Lysozyme levels declined with age, reflecting catabolism of maternal lysozyme transferred via the egg. In captive house sparrows, FR did not significantly impact lysis, a constitutive component of innate immunity, yet levels of the acute‐phase protein haptoglobin, an inducible component of innate immunity, were reduced in FR birds. Birds refed after early FR showed no reduction in haptoglobin response. These findings indicate that significant maturation of the immune system occurs post‐fledging in altricial house sparrows, and may challenge the notion that juveniles depend primarily on innate immune defenses during the growth period. Also, innate immune function appears to be flexible to resource supply during the nestling period, with no evidence of long‐term effects of early FR on development of the innate immune system. Support: NSF‐GRF, AOU, USDA‐Hatch, Birge Fund, GWIS.

HNA‐1d: a new human neutrophil antigen located on Fcγ receptor IIIb associated with neonatal immune neutropenia

Neonatal immune neutropenia (NIN) is a rare, but potentially life-threatening, disorder caused by maternal alloantibodies recognizing paternal neutrophil antigens on fetal cells. Alloantibodies directed against the human neutrophil alloantigen system (HNA)-1 located on Fcγ receptor IIIb (FcγRIIIb) are most frequently implicated in NIN. In this report, we describe two cases of NIN with alloantibodies against FcγRIIIb, which did not match one of the known HNA-1a, -1b, or -1c specificities, but define a new antigen, HNA-1d. Neutrophil-reactive antibodies were detected by agglutination, microscopic immunofluorescence, and monoclonal antibody (MoAb)-specific immobilization of neutrophil antigens (MAIGA) assay. For epitope mapping of FcγRIIIb-reactive antibodies, recombinant chimeric variants of FcγRIIIb were used in the MAIGA assay. Genotyping of FCGR3B was performed by allele-specific polymerase chain reaction. Both mothers were typed FCGR3B*01+, *02-, *03+. Antibody screening revealed the presence of alloantibodies reactive with FcγRIIIb encoded by FCGR3B*02, but not with FcγRIIIb encoded by FCGR3B*03. MAIGA with recombinant, partly chimeric FcγRIIIb variants demonstrated that the antigen recognized by maternal antibodies is characterized by two amino acids, Ala78 and Asp82. Among the FCGR3B alleles, the sequence Ala78---Asn82 is exclusively encoded by FCGR3B *02. A previously unrecognized second antigen, HNA-1d, is present on FcγRIIIb encoded by FCGR3B*02. This antigen is characterized by the sequence Ala78---Asn82. It appears that only individuals carrying the HNA-1c phenotype can form anti-HNA-1d alloantibodies. The HNA-1 system now consists of four antigens encoded by three alleles.

Assessment of the Loop-Mediated Isothermal Amplification Assay for Rapid Diagnosis of &lt;i&gt;Mycoplasma pneumoniae&lt;/i&gt; in Pediatric Community-Acquired Pneumonia

Rapid diagnosis of Mycoplasma pneumoniae pneumonia is required for timely treatment with effective antibiotics; however, PCR-based methods are often too expensive and technologically intensive for general use in clinical practice. In this study, the efficacy of the loop-mediated isothermal amplification (LAMP) assay for diagnosis of M. pneumoniae pneumonia in clinical practice was prospectively evaluated. From July 2011 to March 2012, 531 children hospitalized for community-acquired pneumonia were enrolled. In all patients, throat swabs were obtained on admission for the detection of M. pneumoniae DNA, and paired serum samples were obtained to assay M. pneumoniae particle agglutination (PA) antibody titers. M. pneumoniae pneumonia was diagnosed by either a positive LAMP assay or an increase of 4-fold or greater in the PA titer. Overall, 271 children (51.0% of the patients with pneumonia) were diagnosed with M. pneumoniae pneumonia. Among these, 258 (95.2%) and 248 (91.5%) were identified by the LAMP assay and serological tests, respectively. When the results of serological tests were considered as standard, the sensitivity, specificity, and positive and negative predictive values of the LAMP assay were 94.8%, 91.9%, and 91.1% and 95.2%, respectively. The median duration of pharyngeal carriage, as measured by the LAMP assay, was 9.5 days. Thus, the LAMP assay is useful in the rapid diagnosis of M. pneumoniae pneumonia.

Indirect Particle Agglutination Antibody Testing for Early Diagnosis ofMycoplasma pneumoniaepneumonia in Children

목 적 : 이 연구의 목적은 항체 검사를 어느 시기에 검사해야 마이코플라스마 폐렴을 가장 적절하게 진단을 내릴 수 있는지를 파악하기 위함이다. 방 법 : 2011년 6월부터 2011년 10월까지의 한양대학교병원에서 진단받은 206 명의 폐렴 환아들을 대상으로 후향적으로 분석하였다. 결 과 : 마이코플라스마 폐렴으로 진단받은 160명의 평균 연령은 5.4세이었다. 마이코플라스마 간접입자 응집항체의 측정을 위한 혈청 획득 시간은 마이코플라스마 항체가가 1:640 이상인 혈청들과(8.58일) 1:640 미만인 혈청들(5.44일) 사이에서 통계학적으로 유의한 차이가 있었다(P 【Objectives: Outbreaks of pneumonia caused by Mycoplasma pneumoniae (MP) occur every 3-4 years in Korea, most recently in 2011. The aim of our study was to determine the optimal time to perform indirect particle agglutination antibody assays to improve early diagnosis of MP pneumonia in children. Methods: A database of 206 pediatric patients treated for pneumonia at the Hanyang University Hospital from June to October 2011 was analyzed retrospectively for demographic characteristics and laboratory test results. Results: Among the 206 patients treated for pneumonia during the study period, there were 160 children (mean age, 5.44 years) diagnosed with MP pneumonia, who were studied further. The mean age of these MP pneumonia patients was 5.44 years. Antibody titers increased with increasing time between symptom onset and the collection of serum collection: MP titers were ${\geq}1:640$ for those collected after 8.58 days; P ${\geq}1:640$ . In 42 MP pneumonia patients in whom there was a four-fold or greater increase in titer between successive serum samples, the optimal cut-off time-point for distinguishing between the initial and second titer groups was 7.5 days after the onset of symptoms (sensitivity, 90.5%; specificity, 92.9%). Conclusions: Negative MP antibody titers earlier than 8 days after the onset of symptoms in children with pneumonia may require repeating to confirm the diagnosis. This finding could optimize diagnosis and result in better therapeutic outcomes of MP pneumonia in children.】

Comparison of ABO and Rh-D Blood Group Systems between the Garo Tribal People of Mymensingh and General People of Dhaka City

Background: The distribution pattern of ABO and Rh-D blood group in our country including the tribal people is not fully established as elaborated and large scale studies have not been carried out on it. Therefore this study was designed to observe the distribution pattern of ABO and Rh-D blood groups among the Garo tribes of Mymensingh and general people of Dhaka city. Objectives: To determine and to compare the distribution pattern of ABO and Rh-D blood groups among the Garo tribal people of Mymensingh and general people of Dhaka city and to compare this distribution between this two groups. Materials and Methods: This observational study was conducted in the Department of Physiology, Dhaka Medical College, Dhaka from July 2008 to June 2009. After proper ethical consideration total 900 Garo people of Mymensingh and 784 general people of Dhaka city were included in this study. The Garo localities and the general people of Dhaka city were selected by systematic random sampling. ABO and Rh-D blood groups were determined by the antigen antibody agglutination test of slide method. Chi square statistical analyses were done to compare the results of ABO blood group systems between the Garo people and general people of Dhaka city. Results: This study revealed that there are significant variations in the distribution of ABO and Rh-D blood groups between the Garo tribal people of Mymensingh and the general people of Dhaka city. In this study it was observed that blood group ‘A’ was apparently predominant in Garo population, while blood group ‘B’ was predominant in general population (p&lt;0.001), blood group ‘AB’ and ‘O’ were almost similar in both groups. Rh typing of the participants reveals that majorities of both groups were Rh positive. Rh negative persons are rare in both populations, but it is extremely rare in the Garo population (0.9%). Conclusion: From the findings of the present study it can be concluded that distribution of ABO and Rh-D blood groups varies between the Garo tribal people and the general people of Dhaka city. DOI: http://dx.doi.org/10.3329/jemc.v1i1.11137J Enam Med Col 2011; 1(1): 31-35

Posttransfusion red blood cell (RBC) survival determined using biotin‐labeled RBCs has distinct advantages over labeling with 51Cr

Posttransfusion red blood cell (RBC) survival determined using biotin‐labeled RBCs has distinct advantages over labeling with ⁵¹Cr

Integrated separation of blood plasma from whole blood for microfluidic paper-based analytical devices

Many diagnostic tests in a conventional clinical laboratory are performed on blood plasma because changes in its composition often reflect the current status of pathological processes throughout the body. Recently, a significant research effort has been invested into the development of microfluidic paper-based analytical devices (μPADs) implementing these conventional laboratory tests for point-of-care diagnostics in resource-limited settings. This paper describes the use of red blood cell (RBC) agglutination for separating plasma from finger-prick volumes of whole blood directly in paper, and demonstrates the utility of this approach by integrating plasma separation and a colorimetric assay in a single μPAD. The μPAD was fabricated by printing its pattern onto chromatography paper with a solid ink (wax) printer and melting the ink to create hydrophobic barriers spanning through the entire thickness of the paper substrate. The μPAD was functionalized by spotting agglutinating antibodies onto the plasma separation zone in the center and the reagents of the colorimetric assay onto the test readout zones on the periphery of the device. To operate the μPAD, a drop of whole blood was placed directly onto the plasma separation zone of the device. RBCs in the whole blood sample agglutinated and remained in the central zone, while separated plasma wicked through the paper substrate into the test readout zones where analyte in plasma reacted with the reagents of the colorimetric assay to produce a visible color change. The color change was digitized with a portable scanner and converted to concentration values using a calibration curve. The purity and yield of separated plasma was sufficient for successful operation of the μPAD. This approach to plasma separation based on RBC agglutination will be particularly useful for designing fully integrated μPADs operating directly on small samples of whole blood.

The use of warmed water treatment to induce protective immunity against the bacterial cold-water disease pathogen Flavobacterium psychrophilum in ayu ( Plecoglossus altivelis)

We investigated the induction of protective immunity against bacterial cold-water disease (BCWD) caused by Flavobacterium psychrophilum by warmed water treatment in ayu ( Plecoglossus altivelis). Fish were immersed in a live bacterial suspension (10 7 CFU mL −1) for 30 min and placed in 700 L concrete tanks. The 28 °C warmed water treatment lasted 3 days and began 1, 6, and 24 h after immersion in the live bacterial suspension. A naïve control fish group was immersed in a sterilized modified Cytophaga (MCY) broth instead of the bacterial suspension. Fourteen days after the immersion, agglutination antibody titers against F. psychrophilum were measured by using micro-titer methods. Fish were then exposed to a bacterial bath to infect them with live F. psychrophilum, and cumulative mortality was monitored. Fish treated with warmed water at 1, 6, and 24 h after immersion in the live bacterial suspension had cumulative mortalities of 36%, 30%, and 18%, respectively, all of which were significantly lower than the cumulative mortality of the naïve control fish (90%). Treated fish also showed high antibody titers against F. psychrophilum in agglutination tests. These results demonstrate that warmed water treatment could not only cure BCWD but also immunize the fish against the causative agent F. psychrophilum.

Evaluation of serological tests for diagnosis of Bordetella pertussis infection in adolescents and adults

Bacterial agglutination antibodies against Bordetella pertussis, Yamaguchi and Tohama strains, are frequently measured for serodiagnosis of pertussis infection in Japan. To determine the serological criteria, the comparative titres of bacterial agglutination antibody and anti-pertussis toxin (PT) antibody were evaluated. Antibody titres were analysed in 36 definitive (fourfold increase in agglutination antibody) and 137 presumptive (high titre of single-antibody) cases of B. pertussis infection among adolescents and adults, and in a control group of 318 healthy volunteers. When a single Yamaguchi agglutinin titre of ≥ 1:1280 (> three SD above the geometric mean for the control group) was taken as diagnostic, the sensitivity and specificity at 4-5 weeks after onset of cough were 58% and 98%, respectively. Using this criterion, the clinical findings in presumptive cases were almost identical to those in definitive cases. When the two tests were compared using 318 control sera, there was no association between the Tohama agglutinin titre and the anti-PT antibody titre, whereas a weak association between the Yamaguchi agglutinin titre and the anti-PT antibody titre was observed. When the numbers of pertussis cases with high antibody titres in the two tests were compared, 60% of cases with a Yamaguchi agglutinin titre of ≥1:1280 showed an anti-PT antibody titre of ≥100 EU/mL. These results indicate that the bacterial agglutination test is a method with low sensitivity and specificity for the diagnosis of B. pertussis infection. Therefore, to yield an accurate diagnosis, anti-PT antibody levels should be measured instead of bacterial agglutination antibody.

Enhancement of Eriobotrya japonica extracts on non-specific immune response and disease resistance in kelp grouper Epinephelus bruneus against Vibrio carchariae

The present study investigated the effect of Eriobotrya japonica extracts at 0%, 0.1%, 1.0%, and 2.0% doses supplementation with feed on non-specific immune response, hematological and biochemical profile, and disease resistance against Vibrio carchariae in kelp grouper Epinephelus bruneus at weeks 1, 2, and 4. The white blood cell (WBC) significantly increased in fish fed with 0.1%, 1.0%, and 2.0% diets on weeks 1 and 2 when compared to the control. However, the glucose always decreased from the control except on week 2 against pathogen. The serum total protein, albumin, and globulin significantly increased at week 2 but they did not changed significantly at weeks 1 and 4. The superoxide anion, lymphokines production index, and phogocytosis did not significantly increased in any diet on the first week whereas it was significantly enhanced in 1.0% and 2.0% supplementation diets on weeks 2 and 4 against V. carchariae when compared to control. All diets significantly enhanced the serum lysozyme activity, bactericidal activity, and haemolytic complement activity from weeks 1–4 as compared to control. The serum agglutinating antibody titre did not significantly enhance on the first week whereas it was significantly enhanced on weeks 2 and 4. Fish fed with 1.0% and 2.0% doses diets was found lower mortality than 0.1% diet. Thus, this study suggested that 1.0% and 2.0% doses supplementation diets could be advocated to enhance the immune response and production disease from V. carchariae in E. bruneus.

COMPARISON OF AGGLUTINATING AND GROWTH INHIBITION ANTIBODIES LEVELS IN SOWS IMMUNIZED WITH TWO EXPERIMENTAL INACTIVATED MONOVALENT VACCINES OF CANICOLA SEROVAR: WHOLE CULTURE WITH ALUMINUM HYDROXIDE AND LIPOPOLYSACCHARIDE SUBUNIT WITH LIPID A

ABSTRACT It was compared the antibody response of sows immunized with two experimental vaccines produced with L.interrogans, serovar Canicola, strain LO-4, isolated in Brazil.One of the vaccines was the usual bacterin (whole culture inactivated with phenol and adjuvanted with aluminum hydroxide -WC-AlOH3) and the other one was a subunit vaccine produced with a lipopolysaccharide (LPS) fraction extracted from the bacteria outer envelop and with the lipid A, also extracted from the leptospira wall as adjuvant (LPS-MPLA). Experiment was as follows: group 1 (n = 11), not immunized control, group 2, (n = 11): two immunization with 30 days interval of LPS-MPLA vaccine and group 3 (n = 11): two immunization with 30 days interval of WC-AlOH3 vaccine All three groups were simultaneously immunized, independently of pregnancy stage. Both agglutinin and neutralizing post vaccination antibodies levels were measured respectively by the microscopic sera agglutination with live antigens test (MAT) and the in vitro leptospira growth inhibition test (GIT). Sera collections were performed each 30 days during four months after the first vaccination. Non vaccinated control group animals presented no agglutinating antibodies against Canicola serovar during the whole experiment. At 32 and 68 post vaccination days the agglutinating antibodies levels of group 2 (LPS-MPLA) were significantly higher than the observed in group 3 (WC AlOH3), respectively, p = 0.013 and p = 0.031. The differences observed in the growth inhibition antibodies titers of the two vaccines tested were not significant (p &gt; 0.05). Despite the peak of post-vaccination agglutinins have been registered at 68 days after first immunization, higher levels growth inhibition antibodies were detected at 30 days of first vaccination. Subunit vaccine presented the same immunogenic capacity for the production of neutralizing antibodies as the whole culture one.

Passive immunization with Leptospira LPS-specific agglutinating but not non-agglutinating monoclonal antibodies protect guinea pigs from fatal pulmonary hemorrhages induced by serovar Copenhageni challenge

Leptospira interrogans serovar Copenhageni causes pulmonary hemorrhages with respiratory failure, a major cause of death in leptospirosis patients. Protective immunity to Leptospira is known to correlate with the production of leptospiral lipopolysaccharide (L-LPS)-specific agglutinating antibodies. We generated L-LPS-specific mouse monoclonal antibodies (MAbs) and investigated if these MAbs can protect guinea pigs against fatal pulmonary hemorrhages caused by serovar Copenhageni. The MAbs L8H4 and L9B11 against 22kDa L-LPS agglutinated leptospires and completely protected guinea pigs from the development of fatal pulmonary hemorrhages by serovar Copenhageni, whereas the MAb L4C1 against 8kDa L-LPS neither agglutinated the bacteria nor protected the animals against the fatal pulmonary hemorrhages.

マイクロタイター法による抗ブルセラカニス凝集抗体の検出並びに，溶血による影響の検討

マイクロタイター法による抗ブルセラカニス凝集抗体の検出並びに，溶血による影響の検討

Long lived protection against pneumonic tularemia is correlated with cellular immunity in peripheral, not pulmonary, organs

Protection against the intracellular bacterium Francisella tularensis within weeks of vaccination is thought to involve both cellular and humoral immune responses. However, the relative roles for cellular and humoral immunity in long lived protection against virulent F. tularensis are not well established. Here, we dissected the correlates of immunity to pulmonary infection with virulent F. tularensis strain SchuS4 in mice challenged 30 and 90 days after subcutaneous vaccination with LVS. Regardless of the time of challenge, LVS vaccination protected approximately 90% of SchuS4 infected animals. Surprisingly, control of bacterial replication in the lung during the first 7 days of infection was not required for survival of SchuS4 infection in vaccinated mice. Control and survival of virulent F. tularensis strain SchuS4 infection within 30 days of vaccination was associated with high titers of SchuS4 agglutinating antibodies, and IFN-γ production by multiple cell types in both the lung and spleen. In contrast, survival of SchuS4 infection 90 days after vaccination was correlated only with IFN-γ producing splenocytes and activated T cells in the spleen. Together these data demonstrate that functional agglutinating antibodies and strong mucosal immunity are correlated with early control of pulmonary infections with virulent F. tularensis. However, early mucosal immunity may not be required to survive F. tularensis infection. Instead, survival of SchuS4 infection at extended time points after immunization was only associated with production of IFN-γ and activation of T cells in peripheral organs.

Characterization of a lipopolysaccharide mutant of Leptospira derived by growth in the presence of an anti-lipopolysaccharide monoclonal antibody

A lipopolysaccharide mutant of Leptospira interrogans (LaiMut) was obtained by growth in the presence of an agglutinating monoclonal antibody (mAb) against lipopolysaccharide. Agglutination reactions with anti-lipopolysaccharide mAbs and polyclonal antibodies showed that LaiMut had lost some serogroup Icterohaemorrhagiae agglutinating epitopes. However, LaiMut displayed an increased reactivity to antisera against related serogroups, suggesting that the disruption of some lipopolysaccharide epitopes resulted in greater exposure to cross-reactive epitopes, not accessible to antibodies in the wild type (LaiWT). Comparison of the nucleotide sequences of the lipopolysaccharide loci of LaiMut and Lai wild type (LaiWT) strains showed an inframe stop mutation in the gene encoding undecaprenyl-galactosyltransferase, a protein that provides a fundamental and nonredundant function essential for lipopolysaccharide biosynthesis. Despite this, the biosynthesis of lipopolysaccharide agglutinating antigens was not abolished by the mutation. Based on the phenotype of LaiMut and analysis of the domain structure of the undecaprenyl-galactosyltransferase in relation to the mutation, we propose that the mutation results in the expression of two functional proteins in place of the undecaprenyl-galactosyltransferase. We hypothesize that the loss of coordination of the coupled function afforded by the intact dual function protein present in the parent strain results in an inefficient production of lipopolysaccharide in LaiMut.