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Xenotransplantation 2024Recent clinical xenotransplantation and human decedent studies demonstrate that clinical hyperacute rejection of genetically engineered porcine organs can be reliably...
Recent clinical xenotransplantation and human decedent studies demonstrate that clinical hyperacute rejection of genetically engineered porcine organs can be reliably avoided but that antibody mediated rejection (AMR) continues to limit graft survival. We previously identified porcine glycans and proteins which are immunogenic after cardiac xenotransplantation in non-human primates, but the clinical immune response to antigens present in glycan depleted triple knockout (TKO) donor pigs is poorly understood. In this study we use fluorescence barcoded human embryonic kidney cells (HEK) and HEK cell lines expressing porcine glycans (Gal and SDa) or proteins (tetraspanin-29 [CD9], membrane cofactor protein [CD46], protectin, membrane attack complex inhibition factor [CD59], endothelial cell protein C receptor, and Annexin A2) to screen antibody reactivity in human serum from 160 swine veterinarians, a serum source with potential occupational immune challenge from porcine tissues and pathogens. High levels of anti-Gal IgM were present in all samples and lower levels of anti-SDa IgM were present in 41% of samples. IgM binding to porcine proteins, primarily CD9 and CD46, previously identified as immunogenic in pig to non-human primate cardiac xenograft recipients, was detected in 28 of the 160 swine veterinarian samples. These results suggest that barcoded HEK cell lines expressing porcine protein antigens can be useful for screening human patient serum. A comprehensive analysis of sera from clinical xenotransplant recipients to define a panel of commonly immunogenic porcine antigens will likely be necessary to establish an array of porcine non-Gal antigens for effective monitoring of patient immune responses and allow earlier therapies to reverse AMR.
Topics: Animals; Transplantation, Heterologous; Humans; Swine; Graft Rejection; HEK293 Cells; Veterinarians; Polysaccharides; Animals, Genetically Modified; Antibodies, Heterophile; Heterografts; Immunoglobulin M
PubMed: 38853364
DOI: 10.1111/xen.12865 -
Journal of Immunological Methods Jun 2024Flagellum-mediated motility is essential to Pseudomonas aeruginosa (P. aeruginosa) virulence. Antibody against flagellin reduces motility and inhibits the spread of the...
Flagellum-mediated motility is essential to Pseudomonas aeruginosa (P. aeruginosa) virulence. Antibody against flagellin reduces motility and inhibits the spread of the bacteria from the infection site. The standard soft-agar assay to demonstrate anti-flagella motility inhibition requires long incubation times, is difficult to interpret, and requires large amounts of antibody. We have developed a time-lapse video microscopy method to analyze anti-flagellin P. aeruginosa motility inhibition that has several advantages over the soft agar assay. Antisera from mice immunized with flagellin type A or B were incubated with Green Fluorescent Protein (GFP)-expressing P. aeruginosa strain PAO1 (FlaB+) and GFP-expressing P. aeruginosa strain PAK (FlaA+). We analyzed the motion of the bacteria in video taken in ten second time intervals. An easily measurable decrease in bacterial locomotion was observed microscopically within minutes after the addition of small volumes of flagellin antiserum. From data analysis, we were able to quantify the efficacy of anti-flagellin antibodies in the test serum that decreased P. aeruginosa motility. This new video microscopy method to assess functional activity of anti-flagellin antibodies required less serum, less time, and had more robust and reproducible endpoints than the standard soft agar motility inhibition assay.
PubMed: 38852836
DOI: 10.1016/j.jim.2024.113701 -
Virology Jun 2024Highly pathogenic avian influenza (HPAI) viruses remain a major threat to both the poultry industry and human public health, and these viruses continue to spread...
Highly pathogenic avian influenza (HPAI) viruses remain a major threat to both the poultry industry and human public health, and these viruses continue to spread worldwide. In this study, mice were vaccinated with COBRA H2, H5, and H7 hemagglutinin (HA) and two neuraminidase (NA) proteins, N1 and N2. Vaccinated mice were fully protected against lethal challenge with H5N6 influenza virus. Sera collected after vaccination showed cross-reactive IgG antibodies against a panel of wild-type H2, H5, and H7 HA proteins, and N1 and N2 NA proteins. Mice with pre-existing immunity to H1N1 and H3N2 influenza viruses that were subsequently vaccinated with COBRA HA/NA vaccines had enhanced anti-HA stem antibodies compared to vaccinated mice without pre-existing immunity. In addition, sera collected after vaccination had hemagglutinin inhibitory activity against a panel of H2Nx, H5Nx, and H7Nx influenza viruses. These protective antibodies were maintained up for up to 4 months after vaccination.
PubMed: 38850895
DOI: 10.1016/j.virol.2024.110119 -
Indian Dermatology Online Journal 2024Thymic stromal lymphopoietin (TSLP) is a cytokine initially implicated to be associated with allergic disorders inducing Th2 response. Emerging studies have shown that...
BACKGROUND
Thymic stromal lymphopoietin (TSLP) is a cytokine initially implicated to be associated with allergic disorders inducing Th2 response. Emerging studies have shown that TSLP is also involved in autoimmune diseases. In psoriasis, TSLP acts in synergy with T cell-derived CD40L to promote the release of IL-23 from dendritic cells. IL-23 is responsible for the inappropriate immune reaction and keratinocyte proliferation in psoriasis. Targeting TSLP could be a novel therapeutic approach in the treatment of psoriasis.
OBJECTIVE
To compare the serum levels of TSLP between patients with psoriasis and healthy individuals.
MATERIALS AND METHODS
A prospective hospital-based case-control study was carried out on 38 patients with psoriasis. The severity of psoriasis was graded into mild, moderate, and severe according to PASI. A total of 30 healthy individuals with matched age and sex were taken as controls. 5 ml of venous blood was collected, centrifuged, and the collected serum was stored at -80°C until quantitative assessment by sandwich enzyme-linked immunosorbent assay (ELISA) technique.
RESULTS
TSLP has been found to be significantly elevated in the sera of cases (0.1380178 pg/ml) than in controls (0.1125974 pg/ml). There was also a significant proportionate increase in the mean TSLP with the mean PASI score.
LIMITATIONS
The sample size was small and we could not follow-up the cases to study the changes in TSLP levels with remission of the lesions.
CONCLUSION
We found that serum TSLP was elevated in psoriasis patients and correlated with disease severity, indicating a possible pathogenetic role.
PubMed: 38845675
DOI: 10.4103/idoj.idoj_742_23 -
Scientific Reports Jun 2024Subcutaneous dirofilariasis, caused by the parasitic nematode Dirofilaria repens, is a growing concern in Europe, affecting both dogs and humans. This study focused on...
Subcutaneous dirofilariasis, caused by the parasitic nematode Dirofilaria repens, is a growing concern in Europe, affecting both dogs and humans. This study focused on D. repens Dr20/22, a protein encoded by an alt (abundant larval transcript) gene family. While well-documented in L3 larvae of other filariae species, this gene family had not been explored in dirofilariasis. The research involved cloning Dr20/22 cDNA, molecular characterization, and evaluating its potential application in the diagnosis of dirofilariasis. Although Real-Time analysis revealed mRNA expression in both adult worms and microfilariae, the native protein remained undetected in lysates from both developmental stages. This suggests the protein's specificity for L3 larvae and may be related to a process called SLTS (spliced leader trans-splicing), contributing to stage-specific gene expression. The specificity of the antigen for invasive larvae positions it as a promising early marker for dirofilariasis. However, ELISA tests using sera from infected and uninfected dogs indicated limited diagnostic utility. While further research is required, our findings contribute to a deeper understanding of the molecular and immunological aspects of host-parasite interactions and could offer insights into the parasite's strategies for evading the immune system.
Topics: Animals; Dogs; Dirofilariasis; Dirofilaria repens; Dog Diseases; Antibodies, Helminth; Helminth Proteins; Antigens, Helminth; Larva; Antibody Formation
PubMed: 38839868
DOI: 10.1038/s41598-024-63523-9 -
Vaccine Jun 2024The design of prophylactic and diagnostic tools specific to animal papillomaviruses is hampered by the difficulties of viral in vitro manipulation and by the scarce...
The design of prophylactic and diagnostic tools specific to animal papillomaviruses is hampered by the difficulties of viral in vitro manipulation and by the scarce availability of dedicated biotechnological tools. This paper reports the production of Ovine Papillomavirus 3 (OaPV3)-based virus-like particles (OaPV3-VLPs) in the baculovirus system and their use to investigate host humoral immune response through the establishment of an indirect ELISA test., Polyclonal sera and monoclonal antibodies were generated against OaPV3-VLPs, and their isotype and reactivity were determined. Additionally, antibodies allowed OaPV3 detection in ovine squamous cell carcinoma (SCC) samples by immunohistochemistry. Results encourage the standardization of OaPV3-specific prophylactic and serological diagnostic tools, and open new perspectives for the study of host-viral interaction and SCC development.
PubMed: 38839520
DOI: 10.1016/j.vaccine.2024.06.001 -
Vaccine Jun 2024The level of neutralizing antibodies required to confer protection against COVID-19 breakthrough infections (BIs) is unclear, and the ability to know the immune status...
The level of neutralizing antibodies required to confer protection against COVID-19 breakthrough infections (BIs) is unclear, and the ability to know the immune status of individuals against the rapidly changing endemic variants is limited. We assessed longitudinal serum anti-RBD antibody levels and neutralizing activities (NTs) against Omicron BA.5 and XBB.1.5 in healthcare workers following the fourth monovalent and fifth bivalent BA.4-5 vaccines. The occurrence of BIs was also followed, and pre-infection antibody levels were compared between patients who developed BI and those who did not. In addition, we collected whole blood samples on the same day as the sera and stored them on filter papers (nos. 545, 590, and 424) for up to two months, then measured their NTs using dried blood spots (DBS) eluates, and compared them with the NTs in paired sera. Pre-infection levels of NTs were lower in patients who developed BI than those who did not, but the anti-RBD antibody levels were not different between them. The NTs below 50 % using 200-fold diluted sera might be one of the indicators of high risk for COVID-19 BI. However, the NTs against XBB.1.5 at 6 months after the fifth dose of bivalent BA.4-5 vaccine were lower than this threshold in almost half of infection-naïve participants. NTs measured using DBS eluates were strongly correlated with those measured using paired sera, but the time and temperature stability varied with the type of filter paper; no. 545 filter paper was found to most suitable for NT evaluation.
PubMed: 38839519
DOI: 10.1016/j.vaccine.2024.05.077 -
Toxicon : Official Journal of the... Jul 2024African cobras (Naja species) represent one of the most encountered medically important snakes in Africa. They are classified as African spitting (Afronaja subgenus) and... (Review)
Review Comparative Study
African cobras (Naja species) represent one of the most encountered medically important snakes in Africa. They are classified as African spitting (Afronaja subgenus) and non-spitting cobras (Uraeus and Boulengerina subgenera) with similar and different characteristics. Snake venom toxins including three-finger toxin (3FTx), phospholipase A2 (PLA), and snake venom metalloproteinase (SVMP) cause snakebite envenomation leading to morbidity and mortality. The profile of the proteome of African cobra venoms will help to develop safer and more effective antivenoms. The approval of Captopril by the US Food and Drug Administration (FDA) for the treatment of cardiovascular diseases, has led to intensified research towards possible use of venom toxins as therapeutics. In this review, we compare the venom proteome profile of 3 African Naja subgenera. In both Afronaja and Boulengerina subgenera, 3FTx (Afronaja-69.79%; Boulengerina-60.56%) followed by PLA (Afronaja-21.15%; Boulengerina-20.21%) dominated the venoms compared to the Uraeus subgenus dominated by 3FTx (84.55%) with little to no PLA abundance (0.8%). The venom of subgenus Uraeus was distinct from the other two subgenera by the almost total absence of PLA, thus indicating little or no contribution of PLA in the envenomation caused by Uraeus compared to Afronaja and Boulengerina. Furthermore, we report studies on the experimental testing of African cobra venoms and toxins against diseases including anti-cancer properties.
Topics: Animals; Elapid Venoms; Proteome; Antivenins; Naja; Phospholipases A2
PubMed: 38838860
DOI: 10.1016/j.toxicon.2024.107792 -
Frontiers in Veterinary Science 2024This study aimed to determine the persistent duration of maternal immunity against lumpy skin disease virus (LSDV) in dairy calves born from vaccinated cows using a...
Persistence of passive immunity in calves receiving colostrum from cows vaccinated with a live attenuated lumpy skin disease vaccine and the performance of serological tests.
This study aimed to determine the persistent duration of maternal immunity against lumpy skin disease virus (LSDV) in dairy calves born from vaccinated cows using a virus neutralization test (VNT). The performance of the VNT and an in-house-ELISA test was also determined. Thirty-seven pregnant cows from 12 LSD-free dairy farms in Lamphun province, Thailand were immunized with a homologous Neethling strain-based attenuated vaccine and calved from December 2021 to April 2022. Blood samples from dam-calve pairs were collected within the first week after calving. Subsequently, blood samples were taken from the calves at monthly intervals over a period of 4 months and tested for the humoral immune response using a VNT. The calf sera were also tested with an in-house ELISA test to estimate the accuracy of both tests using a Bayesian approach. For the results, antibodies against LSDV can persist in cows for 4-9 months post-vaccination. Moreover, neutralizing antibodies and LSDV-specific antibodies against LSDV were detected in the majority of calves (75.68%) during the first week after colostrum intake. However, the percentage of seropositive calves declined to zero by day 120, with seropositivity dropping below 50% after day 60. Only a small number of seropositive calves (approximately 13.51%) were observed on day 90. These findings indicated that passive immunity against LSDV can last up to 3 months. The median of posterior estimates for sensitivity (Se) and specificity (Sp) of the VNT were 87.3% [95% posterior probability interval (PPI) = 81.1-92.2%] and 94.5% (95% PPI = 87.7-98.3%), respectively. The estimated Se and Sp for the ELISA test were 83.1% (95% PPI = 73.6-92.6%) and 94.7% (95% PPI = 88.4-98.5%), respectively. In conclusion, this study illustrates the transfer and persistence of maternal passive immunity against LSDV to calves under field conditions. This highlights a potential three-month vaccination gap in calves born from vaccinated cows, while an in-house ELISA test can be used as an ancillary test for LSDV immune response detection. However, further research is required to assess the vaccination protocols for calves as young as 2 months old to precisely determine the duration of maternal immunity.
PubMed: 38835894
DOI: 10.3389/fvets.2024.1303424 -
Parasites, Hosts and Diseases May 2024Malaria is a global disease affecting a large portion of the world's population. Although vaccines have recently become available, their efficacies are suboptimal. We...
Malaria is a global disease affecting a large portion of the world's population. Although vaccines have recently become available, their efficacies are suboptimal. We generated virus-like particles (VLPs) that expressed either apical membrane antigen 1 (AMA1) or microneme-associated antigen (MIC) of Plasmodium berghei and compared their efficacy in BALB/c mice. We found that immune sera acquired from AMA1 VLP- or MIC VLP-immunized mice specifically interacted with the antigen of choice and the whole P. berghei lysate antigen, indicating that the antibodies were highly parasite-specific. Both VLP vaccines significantly enhanced germinal center B cell frequencies in the inguinal lymph nodes of mice compared with the control, but only the mice that received MIC VLPs showed significantly enhanced CD4+ T cell responses in the blood following P. berghei challenge infection. AMA1 and MIC VLPs significantly suppressed TNF-α and interleukin-10 production but had a negligible effect on interferon-γ. Both VLPs prevented excessive parasitemia buildup in immunized mice, although parasite burden reduction induced by MIC VLPs was slightly more effective than that induced by AMA1. Both VLPs were equally effective at preventing body weight loss. Our findings demonstrated that the MIC VLP was an effective inducer of protection against murine experimental malaria and should be the focus of further development.
Topics: Animals; Plasmodium berghei; Mice, Inbred BALB C; Vaccines, Virus-Like Particle; Malaria Vaccines; Malaria; Membrane Proteins; Mice; Protozoan Proteins; Antigens, Protozoan; Female; Antibodies, Protozoan; Parasitemia; CD4-Positive T-Lymphocytes; B-Lymphocytes
PubMed: 38835260
DOI: 10.3347/PHD.24017