Complement Fixation Research Articles

Isolation, serological and molecular methods in screening of Burkholderia mallei in East Azerbaijan province, Iran.

Glanders caused by Burkholderia mallei is one of the most dangerous zoonotic diseases in solipeds. Clinical diagnosis of this disease in its early stages in horses, is difficult. This study investigated serological and molecular identification of B. mallei in East Azerbaijan province. In the third and fourth quarters of 2020, throughout 2021, and in the first and second quarters of 2022, the complement fixation test (CFT) was performed on 350 horses. The malleination was used to confirm the positive CFT cases. Blood samples were taken for culture and for preparing serums to perform the enzyme-linked immunosorbent assay (ELISA). Deep eye discharge, nostril, cutaneous ulcers and lymph fluid swabs were cultured, and polymerase chain reaction (PCR) was carried out. Eleven horses were CFT-positive. Based on the malleination on the 11 horses, six were affected by glanders, five were not affected (false positive), and one horse was CFT-negative despite exhibiting clinical signs. It was positive by malleination, ELISA and PCR. A total number of seven positive cases of glanders were diagnosed. The B. mallei could not be isolated, but the Burkholderia cepacia complex was isolated in one case. Except for three cases, the results of the CFT, mallein and ELISA tests were consistent. The amount of confidence interval was 95.00%. It is suggested that ELISA could be used as a complement to CFT in screening and, if positive results are observed in one of the tests, the entire herd must be examined more accurately using the mallein and western blot confirmatory tests.

Four Cases of Laboratory Acquired Q Fever: Lessons from the Past and a Brief Review of Literature

The aim of this communication is to highlight the dangers of Q fever outbreaks in laboratories attempting isolation of Coxiella burnetii (C. burnetii) and other rickettsiae without Bio Safety Level (BSL)-3 facilities. This series is reported for the benefit of Microbiologists who evince interest in Rickettsial research. Four cases of Laboratory-acquired Q fever is presented among the laboratory personnel in a tertiary care teaching Hospital in Karnataka in 1977, which has not been reported yet. Four persons (one Lecturer, one animal technician and two M.Sc. students) who assisted in blood collection from slaughtered domestic livestock from butcheries and/or participated in the isolation of C. burnetii by guinea pig inoculation became seropositive for Q fever. The presence of antibodies to C. burnetii was demonstrated by two specific serological tests, Micro Agglutination Test (MAT) and Complement Fixation Test (CFT) for Q fever. They responded well to treatment with oxytetracycline, the drug of choice. It should be known that even microscopic demonstration of C. burnetii and other rickettsiae in the ectoparasites is hazardous, due to liberation of infective aerosol in the process. A safe commercial Q fever vaccine for laboratory and farm workers is presently available in Australia alone. Therefore, preventive measures like use of BSL-3 facility in the laboratory as well as animal house, wearing N95 face masks and protective clothing (PPE) are some of the essential precautions to follow so as to prevent laboratory acquired Q fever infection, which is an important occupational hazard.

Avaliação do desempenho analítico de um teste imunocromatográfico rápido para o diagnóstico da brucelose bovina baseado em uma proteína recombinante BP26

ABSTRACT Brucellosis is an important bacterial disease of global distribution with zoonotic potencial. Serological tests used in Brazil for diagnosis of bovine brucellosis, including the Rose Bengal test (RBT), 2-mercaptoethanol (2-ME), fluorescent polarization (FPA), and complement fixation (FC), are based on the smooth lipopolysaccharide antigen (S-LPS) of Brucella abortus. The aim of this study was to evaluate a recombinant BP26 protein used as antigen in a rapid lateral flow immunochromatographic assay (rBP26-LFIA) for serological diagnosis of bovine brucellosis. Analytical performance of rBP26-LFIA was evaluated in positive and negative bovine serum samples previously characterized by RBT and 2-ME. Estimates of analytical sensitivity and specificity were 73.91% and 97.14%, respectively. Bovine sera reactive to Neospora, Trypanosoma vivax or Leptospira were used to assess specificity because these diseases are commonly associated with abortion in cattle. In addition to a possible cross-reaction induced by commercial vaccines against Leptospira in serological tests for bovine brucellosis using S-LPS as an antigen. In conclusion, rBP26-LFIA, with its current standardization, had good analytical performance. However, a future evaluation of diagnostic performance by rBP26-LFIA with samples from regions with known prevalence is necessary for its recommendation for use in the Brazilian program for the control and eradication of bovine brucellosis.

Detectable immunological response in Brucella abortus s 19 vaccinated herds of cattle in vilachchiya veterinary range, north central province, Sri Lanka

Brucellosis a zoonotic disease caused by Gram-negative, intracellular, coccobacillus. Brucellosis, an economically important disease in livestock with zoonotic implications has been reported worldwide. It is transmitted via contaminated animals and their products. Clinical signs of animal brucellosis are abortions, reduced fertility, retention of fetal membranes, endometritis, and substantial decline in milk production over an animal’s lifespan. Orchitis, epididymitis and chronic hygroma had been reported in bulls. The current study focused on to studying the detectable immunological responses to Brucella S 19 live attenuated vaccine using serological tests in cattle of dry zone farms. A questionnaire-based survey was carried out in selected farms with and without a previous history of abortion respectively. Animals that were in 1st to 5th lactation in the 18 farms were selected for screening by Rose Bengal Plate Test (RBPT) and positives were confirmed by Complement Fixation Test (CFT). Three farms each with and without history of abortion were selected for Brucella S19 vaccination from the RBPT and CFT negative farms. Sixty non pregnant heifers over 6 months were selected, and 1ml each of S19 vaccine was given subcutaneously to 30 animals while 30 animals were kept as controls. The serum samples were collected and screened for Brucellosis by RBPT and CFT at 2, 4, 6, 8 and 10 weeks of post vaccination. The second week after the vaccination, 71.42% of the animals showed over 1:4 CFT levels while 28.57% of them did not show any antibody titres for Brucellosis in the Brucella endemic farms. In Brucella non-endemic farms, 68.75% of animals showed over 1:4 CFT titre at 2 weeks after the vaccination. However, 31.25% of animals did not show any CFT titre. No persistent and detectable antibody responses were found 10 weeks post vaccination in heifers of endemic and non-endemic herds. The titers of CFT indicate IgG or IgM humeral response, cell mediated immune response of live attenuated vaccine has not been monitored in the study. Thus, seropositivity after the 10 weeks post vaccination may indicate an infection of Brucellosis since no antibodies from vaccination were found. Further investigation with highly sensitive tests such as ELISA is recommended to have a better insight into this aspect in the future.

Clinical Diagnostic Immunology in A Clinical Microbiology Laboratory

This review unravels the novel approaches, innovations and applications of immunology in the diagnosis of infections in a clinical microbiology laboratory. Many assays or tests in immunology are used in the diagnosis of infections. The availability of monoclonal antibodies has brought rapid progress to this area and they are used , for example , to identify specific microorganisms in culture or in tissues and fluids from infected patients. Examples of common diagnostic applications of antibody- antigen reactions discussed here includes agglutination tests, complement tests, complement fixation tests, ELISA, cytotoxic tests, radioimmunoassay tests, haemagglutination inhibition tests, hypersensitivity tests, phagocytic cell activity test, migration inhibition test, lymphocyte transformation test , lymphocyte fixation test , skin tests, delayed hypersensitivity tests and many others. The development of monoclonal antibody technology and the subsequent availability of unlimited quantities of pure antibody has improved the selectivity of these assays. The development of simple and highly sensitive methods for detection of nucleic acids is being applied to diagnosis of infection using nucleic acid hybridization and this provides a valuable additional aid to immunoassays in the clinical microbiology diagnostic laboratory.

A Comprehensive Review of Brucella canis: Zoonotic Risks and Preventive Strategies

Brucella canis, a zoonotic agent, primarily infects dogs and wild Canidae. Infection is notably suspected in dogs exhibiting epididymitis, infertility, or diskospondylitis. Recent reports indicate a growing incidence of Brucella canis infections in dogs, particularly among those imported into the UK from Eastern Europe. Although human infections by B. canis are relatively uncommon, clinical manifestations are typically mild, yet severe cases can potentially lead to septicemia. The disease in humans is incurable and spreads through contact with fluids from infected animals. Various diagnostic protocols, including Real-time PCR, Rapid slide agglutination test (RSAT), and Complement fixation test (CFT), are employed for the diagnosis of canine brucellosis. These serological tests play a crucial role in diagnosing canine brucellosis. Given the potential zoonotic risks, it is imperative to consistently include B. canis in diagnostic algorithms for canine diseases.

Seroprevalence of brucellosis in communal and smallholder cattle farming in North West Province, South Africa.

Brucellosis is an important bacterial zoonosis responsible for considerable economic losses in livestock and health-related burden worldwide. The objective of this study was to determine the seroprevalence of brucellosis in communal and smallholder cattle farming in four districts of the North West province of South Africa (Dr Ruth Segomotsi Mompati, Ngaka Modiri Molema, Bojanala platinum and Dr Kenneth Kaunda districts). Seven hundred and seventy blood samples from farmed animals (n= 378) and abattoir-slaughtered animals (n= 392) were collected. In addition, milk samples (n= 22) were collected from lactating farmed cows. Rose Bengal test (RBT), complement fixation test (CFT) and milk ring test (MRT) were used to detect antibodies againstBrucellaspecies. The RBT showed a seroprevalence of 2% at 95% confidence interval (CI: 1.35-3.35), CFT confirmed an overall seroprevalence of 1.95% (95% CI: 1.14-3.12) for all four districts sampled. Although the seroprevalence of brucellosis was found to be low, the possibility of undetected cases of the disease could not be ruled out. Overall, the findings of this study confirmed that brucellosis is endemic in the surveyed areas of the North West province of South Africa.Contribution:The outcome of this study will contribute to the National Brucellosis Project organised by the Department of Agriculture, Land Reform and Rural Development (2016-2026) to assist in the effective implementation of the disease control measures with a view to prevent further outbreaks in the country's cattle population.

Microbiota-dependent indole production stimulates the development of collagen-induced arthritis in mice.

Altered tryptophan catabolism has been identified in inflammatory diseases like rheumatoid arthritis (RA) and spondyloarthritis (SpA), but the causal mechanisms linking tryptophan metabolites to disease are unknown. Using the collagen-induced arthritis (CIA) model, we identified alterations in tryptophan metabolism, and specifically indole, that correlated with disease. We demonstrated that both bacteria and dietary tryptophan were required for disease and that indole supplementation was sufficient to induce disease in their absence. When mice with CIA on a low-tryptophan diet were supplemented with indole, we observed significant increases in serum IL-6, TNF, and IL-1β; splenic RORγt+CD4+ T cells and ex vivo collagen-stimulated IL-17 production; and a pattern of anti-collagen antibody isotype switching and glycosylation that corresponded with increased complement fixation. IL-23 neutralization reduced disease severity in indole-induced CIA. Finally, exposure of human colonic lymphocytes to indole increased the expression of genes involved in IL-17 signaling and plasma cell activation. Altogether, we propose a mechanism by which intestinal dysbiosis during inflammatory arthritis results in altered tryptophan catabolism, leading to indole stimulation of arthritis development. Blockade of indole generation may present a unique therapeutic pathway for RA and SpA.

Comparison of coccidioidal complement fixation and quantitative immunodiffusion serology at a reference laboratory.

The incidence of coccidioidomycosis continues to increase. The diagnosis frequently relies on non-invasive diagnostic testing with immunodiffusion and complement fixation (CF) testing the current gold standard. A direct comparison of quantitative immunodiffusion and CF for IgG antibodies has not been previously reported. In a comparison of 368 samples, there was close concordance observed (360/368=97.8%) (P-value<.001). These tests can be considerably interchangeable in the reference laboratory setting.

Diagnosis and Vaccination of Animals that are Affected by Foot and Mouth Disease

A virus that is both highly contagious and economically detrimental, foot and mouth disease primarily impacts animals possessing cloven hooves, including cattle, pigs, sheep, and goats. The FMD virus, responsible for causing foot and mouth disease, exists in seven distinct serotypes, complicating the challenges associated with prevention and control. The main ways that the virus spreads are through direct contact between susceptible and infected animals, contaminated food, and aerosolized viral particles. Owing to its ease of propagation, epidemics can quickly spread throughout cattle populations, resulting in significant financial losses. Fast and accurate diagnosis is crucial to halt the spread of FMD and safeguard the livestock industry. Clinical examination, serological testing, and virus isolation are examples of conventional diagnostic techniques. Several methods like Real-Time Quantitative PCR (RT-qPCR), RT-LAMP, Sandwich ELISA, Complement Fixation test (CFT) and PCR have become essential tools for FMD diagnosis in recent years. These techniques make it possible to identify the virus quickly and precisely, which facilitates the adoption of containment strategies and quick decision-making. Restrictions on migration, immunization, and the culling of diseased animals are all effective control measures. Nonetheless, the management of FMD continues to be based on prevention. Overcoming FMD in the future involves vaccination, strict bio-security protocols on farms, monitoring, and outbreak readiness planning. Sustained investigation and attentiveness are essential to effectively address this persistent problem.

Risk Factor Identification and Incidence Rate Measurement on One High-Risk Farm as Brucellosis Precautions in Metro City Lampung

Since 2011, Lampung is one of the Brucella-free areas, but April 2021 reported abortion case in a cow farm at Metro city Lampung Province. The purpose of this study was to identify risk factors and measure incidence levels as vigilance re-emerging Brucellosis. Sample of cow serum, taken in a census from whole cattle cow in a farm at risk, as much as 2 times with a distance about 1 month. In the first census, 703 serum samples were taken from the stables and 25 samples from the adjacent. Whole sample tested to Brucella spp with rose bengal test (RBT) and positive result confirmed with complement fixation test (CFT). The second census was conducted on samples without positive CFT results in the first census. The positive RBT at second sensus were followed by CFT and c-Elisa tests. Incidence rate of brucellosis in high-risk housing in Banjarsari Village, North Metro District, Metro City 1,67% or 2 brucellosis per 100 cows a month. Brucella spp. seropositivity was significantly related to the type of species and sex of the animal; animals with Ongole breed 4.2 times and female animals 4.5 times have a higher level of exposure compared to non-Ongole breed animals and males.

Acquisition of complement fixing antibodies targeting Plasmodium falciparum merozoites in infants and their mothers in Uganda.

Antibody-mediated complement fixation has previously been associated with protection against malaria in naturally acquired immunity. However, the process of early-life development of complement-fixing antibodies in infants, both in comparison to their respective mothers and to other immune parameters, remains less clear. We measured complement-fixing antibodies in newborns and their mothers in a malaria endemic area over 5 years follow-up and found that infants' complement-fixing antibody levels were highest at birth, decreased until six months, then increased progressively until they were similar to birth at five years. Infants with high levels at birth experienced a faster decay of complement-fixing antibodies but showed similar levels to the low response group of newborns thereafter. No difference was observed in antibody levels between infant cord blood and mothers at delivery. The same result was found when categorized into high and low response groups, indicating placental transfer of antibodies. Complement-fixing antibodies were positively correlated with total schizont-specific IgG and IgM levels in mothers and infants at several time points. At nine months, complement-fixing antibodies were negatively correlated with total B cell frequency and osteopontin concentrations in the infants, while positively correlated with atypical memory B cells and P. falciparum-positive atypical memory B cells. This study indicates that complement-fixing antibodies against P. falciparum merozoites are produced in the mothers and placentally-transferred, and they are acquired in infants over time during the first years of life. Understanding early life immune responses is crucial for developing a functional, long lasting malaria vaccine.

Cytomegalovirus-Seronegative Plus Leukoreduced Blood Products Are Still Superior to Only Leukoreduced Products in Preventing Transfusion-Transmitted Cytomegalovirus Infection

Introduction Cytomegalovirus (CMV) is one of the most important pathogens causing complications after hematopoietic stem cell transplantation (HSCT). Transfusion-transmitted CMV infection (TT-CMV) in CMV-seronegative patients is a major issue. Leukoreduced (LR) blood products were unavailable before 2004. However, they have gradually become widespread, and all blood products in Japan have been LR since 2007. This study aimed to assess the incidence of TT-CMV in CMV-seronegative HSCT recipients undergoing autologous HSCT (auto-HSCT) or allogeneic HSCT (allo-HSCT) from CMV-seronegative stem cell donors, who received transfusions with “CMV-seronegative products” from CMV-seronegative donors or “random donor products” from donors not tested for anti-CMV antibodies during the periods of availability and unavailability of LR products. Methods We retrospectively evaluated 3590 CMV-seronegative recipients registered in the TRUMP database of the Japanese Society for Transplantation and Cellular Therapy from 1999 to 2018. The recipients undergoing HSCT were categorized into three periods: Period A (when LR products were unavailable), 1999-2003 (n = 136); Period B (when there were both non-LR and LR products), 2004-2006 (n = 200); and Period C (when only LR products were available), 2007-2018 (n = 3254). TT-CMV was defined by the presence of CMV antigenemia and/or CMV diseases. This study was approved by the Ethics Committee of Kobe University Hospital and was conducted in accordance with the principles of the Declaration of Helsinki. Results The median age of the patients at HSCT was 40 years (range, 0-79 years). Among auto-HSCT patients (n = 1628) transfused with “CMV-negative products”(CN group) and “random donor products” (RD group), the incidences of TT-CMV in the CN and RD groups were 0% (0/4) and 3.1% (1/32) during Period A (P = 1.0), 22.2% (2/9) and 10.6% (7/66) during Period B (P = 0.29), and 3.8% (4/105) and 5.0% (71/1412) during Period C (P = 0.81), respectively. Among the allo-HSCT patients (n = 1962), the incidences of TT-CMV in the CN and RD groups were 10.0% (3/30) and 27.1% (19/70) during Period A (P = 0.07), 17.9% (5/28) and 29.9% (29/97) during Period B (P = 0.24), and 11.6% (41/355) and 28.0% (387/1382) during Period C (P &amp;lt; 0.001), respectively. During Period C, 99 patients in the CN group always underwent transfusion with leukocyte reduction filters, of which 11 (11.1%) were diagnosed with TT-CMV. In contrast, 202 patients in the CN group always underwent transfusion without the filters, of which 26 (12.9%) were diagnosed with TT-CMV (P = 0.78). In the RD group, 494 patients always underwent transfusion with leukocyte reduction filters, of which 124 (25.1%) were diagnosed with TT-CMV. On the other hand, 807 patients in the RD group always underwent transfusion without the filters, of which 245 (30.4%) were diagnosed with TT-CMV (P = 0.10). Multivariate analysis revealed that random donor products (hazard ratio [HR]: 3.11, 95% confidence interval [CI]: 2.13-4.52; P &amp;lt; 0.001) and age ≥16 years (HR: 2.90, 95% CI: 2.06-4.09; P &amp;lt; 0.001) were associated with an increased risk of TT-CMV in allo-HSCT. No significant difference was observed in the incidence of CMV diseases between the CN group (3.7%; 13/355) and the RD group (3.8%; 52/1382) (P = 1.00). The major CMV diseases included CMV colitis (n = 5) and pneumonia (n = 2) in the CN group, and CMV colitis (n = 30), pneumonia (n = 9), and retinitis (n = 4) in the RD group. Interestingly, among the patients with TT-CMV during Period C, 27/41 patients (65.9%) in the CN group and 333/387 patients (86.1%) in the RD group received early intervention with anti-CMV agents (P = 0.002). The limitation included that complement-fixation test for anti-CMV antibody was used in Japan Marrow Donor Program in this cohort. Conclusion This is the largest study demonstrating that CMV-seronegative plus LR products are still superior to only LR products from random donors in terms of TT-CMV prevention among allo-HSCT CMV-seronegative recipients. However, no significant difference was observed in the incidence of CMV diseases, possibly because of early intervention with anti-CMV agents.

Immunoprophylactic potential of recombinant outer membrane protein of Salmonella enterica serovar Typhi against enteric fever in BALB/c mice

ObjectivesThis study was design to explore the immunogenic behavior of LamB and SpaO outer membrane protein of Salmonella serovar Typhi against enteric fever in BALB/c mice. MethodsSpaO or LamB genes of locally isolated strain of S.Typhi was amplified, cloned and expressed. Recombinant protein SpaO and LamB were purified and lyophilized to prepare aluminum hydroxide Gel precipitated vaccine. Clinical trials were performed in BALB/c mice. The Immunoprophylactic potential of recombinant SpaO or LamB alone and in combination at different concentrations were determined using Complement fixation test along with whole culture attenuated and commercial vaccine. ResultsThe immune response of rSpaO and rLamB proteins in combination at 500 µg/ml was significantly high at 48th day and maintained until 60thday. Protective immune potential of recombinant monovalent and multivalent vaccine assessed upon challenge in mice with 109 cells of S.Typhi virulent culture. Out of five, no mice could survive in control group although rSpaO and rLamB in combination at 500 µg/ml conferred 80 % protection. Whereas the monovalent rSpaO and rLamB vaccine elucidate protection 60 % or 40 % respectively. ConclusionFrom this study, it is conclude that combine vaccine rSpaO and rLamB effectively enhanced the immunological response and withstand the challenge of the causative agent more effectively as compared to the monovalent vaccines.

Correlation of toxoplasmosis with small‑for‑gestational‑age newborns.

Toxoplasma gondii infection in pregnant women could lead to significant changes during the pregnancy, affect the outcomes of pregnancy and the timing of labour. Small‑for‑gestational‑age (SGA) newborns are defined by birthweight below the 10th percentile for gestational age. We tested an association between latent toxoplasmosis in pregnant women and deliveries of SGA babies. For testing, we included 1,647 women who gave birth to a singleton baby at ≥ 37 weeks of gestation. The complement-fixation test (CFT) and enzyme-linked immunosorbent assay (ELISA) tests for IgG and IgM were used. The latent form of toxoplasmosis was defined as a CFT titre of 1:8 or higher, together with index positivity IgG ELISA > 1.1 and negative IgM. There were 406 (24.7 %) women positive, and 1,241 (75.3 %) women negative for latent toxoplasmosis. Of all deliveries. 190 were SGA‑positive and 1,457 were SGA‑negative. Our study found a statistically significant association between latent toxoplasmosis and SGA foetuses born at term. The Pearson chi-square model was statistically significant (χ2(1) = 7.365, p = .007). The odds ratio was 1.567. Pregnant women with latent toxoplasmosis giving birth at ≥ 37 weeks of gestation have a 1.567 times higher risk of delivering an SGA baby (Tab. 2, Fig. 1, Ref. 30).

Investigation of Acute Phase Proteins in Cattle Infected with Mycobacterium bovis

Tuberculosis (TB) is a contagious and zoonotic disease that adversely affects human and animal health, caused by the formation of tubercules in a caseous character in the lungs, other tissues and organs. The causative of the disease is Mycobacterium bovis. An increase or decrease in acute phase protein (APP) levels is observed in various bacterial, viral and parasitic diseases in cattle. Therefore, in this study, it was aimed to determine the changes in the levels of AFPs in cattle infected with M. bovis. In the study, 26 tuberculosis suspected and 10 healthy cattle blood serums collected from various enterprises in Samsun were used. Rose bengal plate test and complement fixation test were applied in serum by taking blood into heparin containing tubes from vena jugularis of cattle. Whole blood samples were subjected to gamma interferon ELISA test. Haptoglobin (Hp), serum amyloid A (SAA), albumin and total protein (TP) levels, which are among the acute phase proteins, were determined in the blood serums taken from the groups. As a result of the analysis, when the AFP levels of the cattle infected with M. bovis and the cattle in the healthy group were compared, it was determined that haptoglobin (p &lt; 0.01), serum amyloid A (p &lt; 0.01) and total protein (p &lt; 0.01) levels, which are AFPs increased statistically significantly compared to the healthy group, while the albümin (p &gt; 0.05) level decreased, but there was no statistically significant difference.&#x0D; Keywords: acute phase protein (APP); cattle; mycobacterium bovis; tuberculosis (TB),

Development and characterization of a prototypic pan-amyloid clearing agent - a novel murine peptide-immunoglobulin fusion.

Systemic amyloidosis is a progressive disorder characterized by the extracellular deposition of amyloid fibrils and accessory proteins in visceral organs and tissues. Amyloid accumulation causes organ dysfunction and is not generally cleared by the immune system. Current treatment focuses on reducing amyloid precursor protein synthesis and slowing amyloid deposition. However, curative interventions will likely also require removal of preexisting amyloid deposits to restore organ function. Here we describe a prototypic pan-amyloid binding peptide-antibody fusion molecule (mIgp5) that enhances macrophage uptake of amyloid. The murine IgG1-IgG2a hybrid immunoglobulin with a pan amyloid-reactive peptide, p5, fused genetically to the N-terminal of the immunoglobulin light chain was synthesized in HEK293T/17 cells. The binding of the p5 peptide moiety was assayed using synthetic amyloid-like fibrils, human amyloid extracts and amyloid-laden tissues as substrates. Binding of radioiodinated mIgp5 with amyloid deposits in vivo was evaluated in a murine model of AA amyloidosis using small animal imaging and microautoradiography. The bioactivity of mIgp5 was assessed in complement fixation and in vitro phagocytosis assays in the presence of patient-derived amyloid extracts and synthetic amyloid fibrils as substrates and in the presence or absence of human serum. Murine Igp5 exhibited highly potent binding to AL and ATTR amyloid extracts and diverse types of amyloid in formalin-fixed tissue sections. In the murine model of systemic AA amyloidosis, 125I-mIgp5 bound rapidly and specifically to amyloid deposits in all organs, including the heart, with no evidence of non-specific uptake in healthy tissues. The bioactivity of the immunoglobulin Fc domain was uncompromised in the context of mIgp5 and served as an effective opsonin. Macrophage-mediated uptake of amyloid extract and purified amyloid fibrils was enhanced by the addition of mIgp5. This effect was exaggerated in the presence of human serum coincident with deposition of complement C5b9. Immunostimulatory, amyloid-clearing therapeutics can be developed by incorporating pan-amyloid-reactive peptides, such as p5, as a targeting moiety. The immunologic functionality of the IgG remains intact in the context of the fusion protein. These data highlight the potential use of peptide-antibody fusions as therapeutics for all types of systemic amyloidosis.

European Inter-Laboratory Proficiency Test for Dourine Antibody Detection Using the Complement Fixation Test.

Dourine is a sexually transmitted parasitic disease affecting equids. Its causative agent is referred to as Trypanosoma equiperdum and the prescribed serodiagnosis method is the complement fixation test (CFT). In the context of our European Reference Laboratory mandate for equine diseases (excluding African horse sickness), we organised dourine CFT inter-laboratory proficiency tests (ILPTs) in 2015, 2018 and 2022 to evaluate the performance of the European Union network of National Reference Laboratories (NRLs) for dourine. ILPT panels were composed of horse sera with or without antibodies against Trypanosoma spp. originating from non-infected, immunised or experimentally infected horses. Twenty-two NRLs participated in at least one of the three sessions. In 2015, 2018 and 2022, the percentage of laboratories obtaining 100% of the expected results was 57, 90 and 80, respectively. These dourine CFT ILPTs showed the benefits of standardising the method's detection limit and underlined the constant need to evaluate NRLs to improve the network's performance. These results also argue in favour of the need for a representative bio-bank to improve the representativeness of ILPT samples and to allow the adoption of alternative serological methods for international surveillance of dourine.

Herd and animal level seroprevalence and associated risk factors of small ruminant brucellosis in the Korahey zone, Somali regional state, eastern Ethiopia.

Brucellosis is a zoonosis of major public health and economic importance that is endemic in livestock in Ethiopia with varying levels of seroprevalence. A cross-sectional study was carried out to determine the individual and herd-level seroprevalence of brucellosis in small ruminants in the Korahey zone of the Ethiopian Somali Region. A total of 324 sera from 63 herds of small ruminants were collected randomly using a multistage sampling technique and the sera were tested using the Rose Bengal Plate Test, and seropositive reactors were confirmed by the Complement Fixation Test. The seroprevalence of brucellosis at the herds and the individual level was 6.35% (95% CI: 0.0-13%) and 1.23% (95% CI: 0.0-2%), respectively; with 1.4% in goats and 0.9% in sheep. Moreover, predicted variables like age group, parity, history of abortion, fetal membranes, herd size, ownership of other livestock species, contact with wild animals in the past year, the introduction of new animals in the past year, and lending of breeding males in the past year were not significantly associated (p > 0.05) with Brucella seropositivity at individual and herd level seroprevalence during multivariable logistic regression analysis. Pastoral community awareness regarding the public health impact of brucellosis and the promotion of an intersectoral One Health approach for the effective control of brucellosis is recommended.

Bioactive polysaccharides in different plant parts of Aconitum carmichaelii.

Aconitum carmichaelii is an industrially cultivated medicinal plant in China and its lateral and mother roots are used in Traditional Chinese Medicine due to the presence of alkaloids. However, the rootlets and aerial parts are discarded after collection of the roots, and the non-toxic polysaccharides in this plant were less concerned than the alkaloids and poisonous features. In this study, five neutral and 14 acidic polysaccharide fractions were systematically isolated from different plant parts of A. carmichaelii, and their structural features and bioactivities were studied and compared. The neutral fraction isolated from the rootlets was different from those isolated from the lateral and mother roots, consisting of less starch and more possible mannans, galactans, and/or xyloglucans, which was similar to those of the aerial parts. Pectic polysaccharides containing homogalacturonan and branched type-I rhamnogalacturonan (RG-I) were present in all plant parts of A. carmichaelii. However, more arabinogalactan (AG)-II side chains in the RG-I backbone were present in the aerial parts, while more arabinans followed by AG-I/II were found in the roots. Various immunomodulatory effects determined by complement fixation activity and anti-inflammatory effects on intestinal epithelial cells IPEC-J2 of all polysaccharide fractions were observed. This study highlighted the diversity of polysaccharides present in A. carmichaelii, especially in the unutilized plant parts, and showed their potential medicinal values. This article is protected by copyright. All rights reserved.