Strain RB51 Research Articles

Brucella rough RB51 infection activates P53-Slc7a11-Gpx4/GSH pathway to induce ferroptosis to attenuate the intracellular survival on macrophages

B. abortus is a facultative intracellular bacterium that replicates within macrophages. Intracellular survival is one of the important indexes to evaluate the virulence of Brucella. Ferroptosis is a type of programmed cell death induced by the accumulation of free iron, reactive oxygen species (ROS), and toxic lipid peroxides, play roles on cancers, cardiovascular diseases, and inflammatory diseases. In this study, we found that Brucella rough strain RB51 induced ferroptosis on macrophages with reduced levels of host glutathione and glutathione peroxidase 4 (Gpx4), together with increased ferrous iron, lipid peroxidation, and ROS. The inhibitor ferrostatin-1 significantly reduced the ferroptosis of RB51-infected macrophages, confirming that ferroptosis occurred during infection with Brucella RB51. Furthermore, we found that RB51 infection induced ferroptosis is regulated by P53-Slc7a11-Gpx4/GSH signal pathway. Inhibiting P53 decreased the levels of ROS and lipid peroxidation, while the levels of Slc7a11, Gpx4 and GSH were rescued. More importantly, inhibiting ferroptosis by different ferroptosis inhibitors increased the intracellular survival of Brucella RB51, indicating ferroptosis functions on the attenuation of Brucella intracellular survival. Collectively, our observations demonstrate that Brucella RB51 infection induces ferroptosis on macrophages, which is regulated by P53-Slc7a11-Gpx4/GSH signal pathway and functions on the attenuation of intracellular survival of Brucella.

Characterization of the adaptive cellular and humoral immune responses to persistent colonization of Brucella abortus strain RB51 in a Jersey cow.

Brucella abortus strain RB51 is the commercial cattle vaccine used in the United States (US) and many parts of the world against bovine brucellosis. RB51 was licensed for use in 1996, and it has been shown to be safe and efficacious in cattle, eliciting humoral and cellular responses in calves and adult animals. In 2017, an epidemiological trace-back investigation performed by the Centers for Disease Control and Prevention (CDC) identified human cases of brucellosis caused by infection with RB51. These infections resulted from the consumption of unpasteurized dairy products, which were traced back to otherwise healthy animals that were shedding RB51 in their milk. At the current time, six adult Jersey cows have been identified in the U.S. that are shedding RB51 in milk. One of the RB51 shedding cattle was obtained and housed at the National Animal Disease Center (NADC) for further study. Improved understanding of host cellular and humoral immune responses to RB51 in persistently colonized cattle may be achieved by the characterization of responses in shedding animals. We hypothesized, based on the lack of RB51 clearance, that the RB51 shedder animal has a diminished adaptive cellular immune response to RB51. Our data demonstrate that in the presence of persistent RB51 infection, there is a lack of peripheral anti-RB51 CD4+ T cell responses and a concurrently high anti-RB51 IgG humoral response. By understanding the mechanisms that result in RB51 persistence, the development of improved interventions or vaccinations for brucellosis may be facilitated, which would provide public health benefits, including reducing the risks associated with the consumption of non-pasteurized milk products.

Effect of selection genotype on immune response to Brucella abortusRB51 in Holstein cattle.

Genetic selection for milk production traits in US Holsteins has affected numerous genes associated with reproduction and immunity. This study compares the transcriptomic response of peripheral blood mononuclear cells to an invitro Brucella abortus strain RB51 (RB51) bacterial challenge between contemporary Holsteins and Holsteins that have not been selected for milk production traits since the mid-1960s. Total RNA was extracted from peripheral blood mononuclear cells from four contemporary and four unselected lactating, primiparous cows following 24-h incubation with or without stimulation with RB51 bacteria. RNA was sequenced and reads analyzed using tools from galaxy.scinet.usda.gov. A total of 412 differentially expressed genes (false discovery rate p < 0.05, log fold change > |1|) were identified. The upregulated genes (genes with higher expression in contemporary than unselected cattle) were enriched for 19 terms/pathways, including alanine, aspartate, and glutamate metabolism, indicating a cellular stress response. Downregulated genes (genes with higher expression in unselected than contemporary cows) were enriched for 37 terms/pathways, representing diverse immune responses, including natural killer cell-mediated immunity, interferon-γ production, negative regulation of interleukin-10 production, and cytokine receptor activity indicating a broad immune response with an emphasis on immune defense. These results provide evidence that differences exist between the two genotypes in response to invitro bacterial challenge. This suggests that contemporary cows, genetically selected for milk production, may have reduced immune function, including limitations in response to intracellular bacteria.

Serological, cultural, and molecular analysis of Brucella from Buffalo milk in various regions of Iran.

Brucellosis is a significant infection that causes abortion, decreased milk production, and sterility in livestock, which greatly affects the industry. This study aimed to determine the prevalence of Brucella in buffalo milk samples across various regions of Iran, utilizing serological, molecular, and cultural analyses. A total of 1860 buffalo milk samples were collected from industrial, semi-industrial, and traditional buffalo farms in four major buffalo breeding provinces. The milk ring test agglutination test (MRT) was initially conducted on all milk samples, followed by culture and molecular testing for positive and negative samples in MRT. The study revealed positive results for the presence of Brucella DNA in various provinces of Iran. The MRT had a relatively low sensitivity, with results ranging from 0 to 0.7% in different provinces. However, the AMOS PCR method showed a significantly higher presence of Brucella DNA, ranging from 13 to 46% in these provinces. The highest abundance of Brucella bacterial DNA was found in Ardabil province, while the lowest was in West Azerbaijan province. Brucella abortus was the most commonly detected bacteria, followed by Brucella melitensis. Interestingly, the B. abortus vaccine strain RB51 was detected in 26.3% of positive samples of B. abortus. The culture assay of milk samples further confirmed the presence of B. melitensis biovar 1 in one sample from Khuzestan province. Overall, the study emphasizes that the AMOS PCR method is the most sensitive in detecting Brucella-exposed milk, while the sensitivity of milk sample culture and MRT is relatively lower.

Comparison of diagnostic tests for detecting bovine brucellosis in animals vaccinated with S19 and RB51 strain vaccines.

The diagnosis of bovine brucellosis in animals vaccinated with strain-19 (S19) and Rose Bengal (RB)-51 strain vaccines can be misinterpreted due to false positives. This study aimed to compare diagnostic tests for detecting bovine brucellosis in animals vaccinated with S19 and RB51 vaccine strains. Two groups of 12 crossbred Holstein calves between 6 and 8 months of age were used. On day 0, blood samples were collected from the animals, and the competitive enzyme-linked immunosorbent assay was used for serological diagnosis of bovine Brucellosis. All animals tested negative. After the first blood collection, the animals were subcutaneously vaccinated: one group received the S19 vaccine and the other received the RB51 vaccine. From the 3rd month after vaccination, all animals were sampled. Sampling was repeated every 2 months until the 7th month. Serological diagnosis of bovine brucellosis was performed using RB, tube serum agglutination test (SAT), SAT with 2-mercaptoethanol (SAT-2Me), and fluorescence polarization assay (FPA). Animals vaccinated with S19 showed positive results with the RB, SAT, and SAT-2Me tests in all months of post-vaccination diagnosis. In animals vaccinated with S19, FPA showed positive results at months 3 and 5 and negative results at month 7, indicating that this test discriminates vaccinated animals from infected animals 7 months after vaccination. Rose Bengal, SAT, SAT-2Me, and FPA tests showed negative results in animals vaccinated with RB51 in all months of diagnosis. Animals vaccinated with S19 may test positive for brucellosis using RB, SAT, or SAT-2Me tests 7 months later. Fluorescence polarization assay is an optimal alternative for diagnosing animals in the field, thereby preventing false positives, and consequently, unnecessary confiscations of animals. Animals vaccinated with RB51 tested negative with RB, SAT, SAT-2Me, and FPA tests in all months of diagnosis, confirming that the tests are ineffective for diagnosing brucellosis caused by rough strains.

Brucella abortus Strain RB51 Administered to Prepubescent Water Buffaloes, from Vaccination to Lactation: Kinetics of Antibody Response and Vaccine Safety.

Brucella RB51 is a live modified vaccine. Its use in water buffalo has been proposed using a vaccination protocol different to that used for cattle, but knowledge of the long-term effects of RB51 vaccination in this species remains incomplete. The aim of the study was to evaluate the safety and kinetics of antibody responses in water buffaloes vaccinated according to the protocol described for the bovine species in the WOAH Manual, modified with the use of a triple dose. Water buffaloes were vaccinated with the vaccine RB51. A booster vaccination was administered at 12 months of age. When turning 23-25 months old, female animals were induced to pregnancy. RB51-specific antibodies were detected and quantified using a CFT based on the RB51 antigen. Vaccinated animals showed a positive serological reaction following each vaccine injection, but titers and the duration of the antibody differed among animals. For 36 weeks after booster vaccination, the comparison of CFT values between vaccinated and control groups remained constantly significant. Afterwards, antibody titers decreased. No relevant changes in antibody response were recorded during pregnancy or lactation. In conclusion, results indicated that the vaccination schedule applied is safe and allows for vaccinated and unvaccinated controls to be discriminated between for up to 8 months after booster vaccination.

Effect of the Lacticaseibacillus paracasei JLM Strain Against Brucella abortus Strains in Ripened Cheese

This study evaluated the antagonistic effect of the Lacticaseibacillus paracasei JLM strain isolated from aguamiel, against Brucella abortus RB51, S19, and 2308 strains, during the manufacture of soft-ripened cheese. First, the tolerance of Lc. paracasei JLM was tested with pH values and bile salt concentrations for 3 h to simulate digestive tract conditions. The antagonistic effect against B. abortus strains was evaluated through double-layer diffusion and agar well diffusion assays. In addition, the stability of the cell-free supernatant (CFS) was tested with the agar well diffusion method under different conditions of temperature, pH, and treatment with digestive enzymes. Finally, the antagonistic effect against B. abortus strains was observed during the manufacture of ripened cheese for 31 days at 4°C and 25°C using the Lc. paracasei JLM strain as starter culture. The results showed that the Lc. paracasei JLM strain remains viable after exposure to different pH values (from 3.00 to 7.00) and concentrations of bile salts (from 0.5% to 7%). Moreover, the results demonstrate that the growth of the three B. abortus strains was inhibited in both antagonism tests and that CFS maintained 86% activity after heat treatment at 100°C, 121°C, or enzymatic digestion (proteinase K, trypsin, chymotrypsin), but it was inactivated at pH levels above 6. Finally, Lc. paracasei JLM completely inhibited the growth of B. abortus in ripened cheese at 25°C from day 17 and showed greater inhibition on the B. abortus RB51 strain in the ripened cheese at 4°C, showing statistical differences for the B. abortus S19 and B. abortus 2308 strains. The current research concluded that the Lc. paracasei JLM strain has an antagonistic effect on B. abortus, enhancing the potential of its use in the future as a probiotic.

Effects of concurrent administration of modified live viral vaccines with RB51 on immune responses to RB51.

Brucella abortus is a gram negative, zoonotic pathogen that can cause abortions and stillbirths in the cattle industry and has contributed to significant economic losses to cow-calf producers. Cell mediated immunity (CMI) is an important component of the immune response associated with protection against Brucella abortus and other intracellular pathogens. Brucellosis and viral modified live vaccines (vMLV) are licensed individually but may be used concurrently under field conditions. Peripheral blood mononuclear cells (PBMC) from non-vaccinated cattle and cattle vaccinated with either Brucella abortus strain RB51, a vMLV or both RB51 and a vMLV vaccine were isolated. The frequency of CD4+, CD8+ and γδ+ T cell populations within PBMC, and the frequency of interferon gamma (IFN-γ) production within these cell types was characterized via flow-cytometry. The goal of this study was to characterize immune responses to RB51 vaccination and determine the effect of concurrent vaccine administration. Although immune responses were greatest in PBMC from cattle vaccinated with only RB51, cattle vaccinated with both RB51 and vMLV demonstrated measurable T cell responses associated with protective immunity. Data suggests a lack of significant biological differences between the groups in protective immune responses. Collectively, our data demonstrated a lack of vaccine interference following concurrent administration of vMLV and RB51. Although concurrent administration of individually licensed vaccines may influence immune responses and contribute to vaccine interference, potential vaccine combinations should be evaluated for biological effects.

Brucella abortus induces mast cell activation through TLR-2 and TLR-4

The Gram-negative bacteria Brucella abortus is a major cause of brucellosis in animals and humans. The host innate immune response to B. abortus is mainly associated with phagocytic cells such as dendritic cells, neutrophils, and macrophages. However, as mast cells naturally reside in the main bacterial entry sites they may be involved in bacterial recognition. At present, little is known about the role of mast cells during B. abortus infection. The role of the innate immune receptors TLR2 and TLR4 in activation of mast cells by B. abortus (strain RB51) infection was analyzed in this study. The results showed that B. abortus did not induce mast cell degranulation, but did induce the synthesis of the cytokines IL-1β, IL-6, TNF-α, CCL3, CCL4, and CCL5. Furthermore, B. abortus stimulated key cell signaling molecules involved in mast cell activation such as p38 and NF-κB. Blockade of the receptors TLR2 and TLR4 decreased TNF-α and IL-6 release by mast cells in response to B. abortus. Taken together, our results demonstrate that mast cells are activated by B. abortus and may play a role in inducing an inflammatory response during the initial phase of the infection.

Characterization of the duration of immunity of Brucella abortus strain RB51 vaccination in cattle after experimental challenge

Fifty-two, Hereford heifers were obtained from brucellosis-free herds and randomly assigned to Brucella abortus strain RB51 (RB51) vaccination (n = 32) or control (n = 20) treatments. Vaccinates received 1010 colony-forming units (CFU) of a commercial lyophilized RB51 vaccine. Immunologic responses after inoculation demonstrated significantly greater (P < 0.05) antibody, interferon-γ responses, and proliferative responses to RB51 antigens in cattle vaccinated with RB51 as compared to controls. A subgroup of control and vaccinated cattle were experimentally challenged at approximately 4, 5, and 6 years after inoculation with 107 CFU of B. abortus strain 2308 at 170–180 days gestation. After experimental challenge, 6 of 14 (43 %) control animals aborted at a higher rate (P < 0.05) when compared to RB51 vaccinates in years 4 and 5, but not year 6 (0 %, 10 %, and 50 %, respectively). When comparing recovery of Brucella from all tissues except head lymph nodes draining the site of challenge, RB51 vaccinates had reduced infection rates (P < 0.05) after experimental challenge at 4 years (14 %), but not at 5 or 6 years (78 % and 67 %, respectively) when compared to non-vaccinated cattle (93 %). Our data suggests that calfhood vaccination with RB51 does not induce lifelong immunity and suggests implementation of booster vaccination by 4–5 years of age should be utilized in endemic areas to maintain high levels of protection.

Survival of Brucella abortus RB51 and S19 Vaccine Strains in Fresh and Ripened Cheeses.

Brucellosis is a zoonotic infection caused by the consumption of contaminated raw milk and dairy products. This study aims to compare survival rates of Brucella abortus RB51 and S19 vaccine strains to that of virulent B. abortus 2308 strain during the manufacture of fresh and ripened cheeses. To do this, we inoculated fresh pasteurized milk with B. abortus RB51, S19, or 2308 at a 6 × 108 colony-forming unit per milliliter concentration during the cheese making process. Cheese was manufactured at room temperature, then, fresh cheeses were conserved at either 4°C or 25°C for 7 days, while ripened cheeses were conserved for 31 days at the same temperatures. We measured B. abortus survival and pH values during different stages of the process. Our results confirm that all three strains can maintain viable cells in both types of cheeses throughout the process. Survival of B. abortus RB51 was 10 times lower than was the survival of the B. abortus S19 and B. abortus 2308 strains in both fresh and ripened cheeses. Our results also suggest that both temperature and pH can condition Brucella survival. In conclusion, B. abortus RB51 and S19 vaccine strains can survive throughout the manufacture and conservation processes of both fresh and ripened cheeses. In turn, this implies a potential health risk if cheeses contaminated with these strains were to be consumed.

Design and Characterization of a Recombinant Brucella abortus RB51 Vaccine That Elicits Enhanced T Cell-Mediated Immune Response.

Brucella abortus vaccines help control bovine brucellosis. The RB51 strain is a live attenuated vaccine with low side effects compared with other live attenuated brucellosis vaccines, but it provides insufficient protective efficacy. Cell-mediated immune responses are critical in resistance against intracellular bacterial infections. Therefore, we hypothesized that the listeriolysin O (LLO) expression of Listeria monocytogenes, BAX, and SMAC apoptotic proteins in strain RB51 could enhance vaccine efficacy and safety. B. abortus RB51 was transformed separately with two broad-host-range plasmids (pbbr1ori-LLO and pBlu–mLLO-BAX-SMAC) constructed from our recent work. pbbr1ori-LLO contains LLO, and pBlu–mLLO-BAX-SMAC contains the mutant LLO and BAX-SMAC fusion gene. The murine macrophage-like cell line J774A.1 was infected with the RB51 recombinant strain containing pBlu-mLLO-BAX-SMAC, RB51 recombinant strain containing LLO, and RB51 strain. The bacterial cytotoxicity and survival and apoptosis of host cells contaminated with our two strain types—RB51 recombinants or the parental RB51—were assessed. Strain RB51 expressing mLLO and BAX-SMAC was tested in BALB/c mice and a cell line for enhanced modulation of IFN-γ production. LDH analysis showed that the RB51-mLLO-BAX-SMAC and RB51-LLO strains expressed higher cytotoxicity in J774A.1 cells than RB51. In addition, RB51 recombinants had lower macrophage survival rates and caused higher levels of apoptosis and necrosis. Mice vaccinated with the RB51 recombinant containing mLLO-BAX-SMAC showed an enhanced Th1 immune response. This enhanced immune response is primarily due to bacterial endosome escape and bacterial antigens, leading to improved apoptosis and cross-priming. This potentially enhanced TCD8+- and T cell-mediated immunity leads to the increased safety and potency of the RB51 recombinant (RB51 mLLO-BAX-SMAC) as a vaccine candidate against B. abortus.

Immune response and recent advances in diagnosis and control of brucellosis

Brucellosis is a zoonotic disease that has serious animal welfare and economic consequences worldwide. In mammals, this stealthy intracellular pathogen causes abortion and infertility, and in humans, it produces a terrible febrile illness that can progress into a long-term condition with serious implications. The pathogenicity of brucellae is based on their ability to survive and replicate in host cells, which allows them to escape from the immune system. The gold standard test for diagnosis, which demands competence, is still isolation and identification. Advancements in diagnostic procedures and screening of recently infected animals are required to achieve effective control. Despite their drawbacks, the most widely used vaccine strains to protect against Brucella infection and relevant abortions in cattle are B. abortus strains S19 and RB51 and in small ruminants is B. melitensis Rev1. However, there are no safe vaccine candidates for humans. Therefore, it is critical needs to improve vaccine production using advanced techniques such as subunit vaccines that are both effective and safe. Studying the overview of the Brucella immune response mechanism and advances in the diagnosis procedures allow more understanding of effective control strategies. The current review provides an overview on the immune response and updates on the diagnosis and control of brucellosis based on published literature on different search engines

SEROLOGICAL RESPONSE IN CROSS-BRED HEIFERS IMMUNIZED WITH BRUCELLA ABORTUS STRAIN RB51 VACCINE UNDER SMALLHOLDER DAIRY FARM MANAGEMENT SYSTEM IN BANGLADESH

Background: Brucella abortus live vaccines (strains 19 and RB51) have successfully been used to control bovine brucellosis especially to protect cattle against infection and abortion worldwide. Most of the knowledge of the protective immune response of these vaccines against brucellosis induced by immunization derives from the studies in mice. Some studies on humoral immune response of these vaccines have been studied in bovine and buffaloes and an attempt is made further to evaluate the serological responses of RB51 vaccine in cross-bred heifers of smallholder dairy farms in Bangladesh. Objective: This study was conducted to measure serological responses induced in cross-bred dairy heifers immunized with RB51 Brucella abortus vaccine by using indirect ELISA. Materials and Methods: Five cross-bred (Holstein  Local) heifers were selected for this experiment which aged four months and sero-negative for Brucella infection in smallholder dairy farms in the district of Kushtia. Each of the selected heifer received 2.0 ml imported commercial B. abortus RB51 strain vaccine subcutaneously in the neck region at day 0 and then booster dose at 60 days after the first vaccination with similar dose and route during the period from January to July 2020. Each of the collected serum samples of five heifers at day 0, 7, 14, 21, 28, 60, 90, 120 and 150 was tested to detect the antibody status by using commercial indirect ELISA kit. Results: The serological responses (antibody level) was detected by commercial indirect ELISA OD values in the serum of cross-bred heifers induced by using B. abortus strain RB51 commercial live vaccine resulted 0.097 OD value at 0 day (pre-vaccination) and 0.108 at 7th day of post-immunization. It appears that the OD values in the immunized heifers was started to rise from the first week and it was gradually increased and reached the peak level at 60 days (OD value 0.223). Booster vaccination administered at 60 days was resulted peak antibody level at day 90 (OD value 0.313) but its level was started to decline from 120 days with a highest declined at day 150 (OD value 0.199). Conclusions: Further studies to define the cellular immune response and protection against B. abortus infection are recommended before routine use of the vaccine in cattle in Bangladesh.

SEROLOGICAL RESPONSE IN CROSS-BRED HEIFERS IMMUNIZED WITH BRUCELLA ABORTUS STRAIN RB51 VACCINE UNDER SMALLHOLDER DAIRY FARM MANAGEMENT SYSTEM IN BANGLADESH

Background: Brucella abortus live vaccines (strains 19 and RB51) have successfully been used to control bovine brucellosis especially to protect cattle against infection and abortion worldwide. Most of the knowledge of the protective immune response of these vaccines against brucellosis induced by immunization derives from the studies in mice. Some studies on humoral immune response of these vaccines have been studied in bovine and buffaloes and an attempt is made further to evaluate the serological responses of RB51 vaccine in cross-bred heifers of smallholder dairy farms in Bangladesh. Objective: This study was conducted to measure serological responses induced in cross-bred dairy heifers immunized with RB51 Brucella abortus vaccine by using indirect ELISA. Materials and Methods: Five cross-bred (Holstein  Local) heifers were selected for this experiment which aged four months and sero-negative for Brucella infection in smallholder dairy farms in the district of Kushtia. Each of the selected heifer received 2.0 ml imported commercial B. abortus RB51 strain vaccine subcutaneously in the neck region at day 0 and then booster dose at 60 days after the first vaccination with similar dose and route during the period from January to July 2020. Each of the collected serum samples of five heifers at day 0, 7, 14, 21, 28, 60, 90, 120 and 150 was tested to detect the antibody status by using commercial indirect ELISA kit. Results: The serological responses (antibody level) was detected by commercial indirect ELISA OD values in the serum of cross-bred heifers induced by using B. abortus strain RB51 commercial live vaccine resulted 0.097 OD value at 0 day (pre-vaccination) and 0.108 at 7th day of post-immunization. It appears that the OD values in the immunized heifers was started to rise from the first week and it was gradually increased and reached the peak level at 60 days (OD value 0.223). Booster vaccination administered at 60 days was resulted peak antibody level at day 90 (OD value 0.313) but its level was started to decline from 120 days with a highest declined at day 150 (OD value 0.199). Conclusions: Further studies to define the cellular immune response and protection against B. abortus infection are recommended before routine use of the vaccine in cattle in Bangladesh.

Immune Responses and Efficacy of Brucella Abortus Strain RB51 in Bison After Delivery in a Dry Dart Formulation or by Parenteral Inoculation.

Bison (Bison bison) heifer calves (n = 32) were randomly assigned to control or vaccination with 1010 colony-forming units of Brucella abortus strain RB51 (RB51) vaccine by single or boostered parenteral delivery, or by surgical implantation of a dry dart formulation (n = 8/trt). Serum and/or peripheral blood mononuclear cells (PBMC) were obtained at 0, 4, 8, 13, 16, 21, and 24 wks after initial vaccination and at 0, 4, 8, 12, 15, 22, and 27 wks after booster vaccination to characterize humoral and cellular immune responses to RB51. Bison in both RB51 vaccination treatments demonstrated greater (P < 0.0001) serum humoral responses when compared to non-vaccinates, with parenteral vaccinates demonstrating greater (P < 0.01) responses when compared to mean responses of bison inoculated with the dry dart. Only the booster vaccinated treatment demonstrated greater (P < 0.0001) humoral responses than control bison in samples collected after re-inoculation. At 4, 8, 12, 16, and 24 wks after initial vaccination, PBMC from parenteral RB51 vaccinates demonstrated greater proliferative responses to RB51 when compared to responses of control animals. In comparison, bison inoculated with the RB51 dry dart did not demonstrate greater (P > 0.05) proliferative responses when compared to responses of non-vaccinates. Bison were pasture bred and pregnant animals experimentally challenged in mid-gestation with 107 CFU of B. abortus strain 2,308. Bison in parenteral vaccination treatments had reduced (P < 0.05) abortions and infection in uterine and fetal samples as compared to non-vaccinated bison, with booster vaccinates tending to have the lowest colonization (CFU/gm) in tissues. In comparison, the dry dart formulation did reduce abortion (P < 0.05) but not infection (P > 0.05) in most tissues when compared to non-vaccinated bison. The results of this study reaffirm the efficacy of boostered parenteral vaccination of bison with RB51 in preventing brucellosis. Our data also suggests that the novel dry dart RB51 formulation does not induce sufficient efficacy in bison after a single inoculation.

Generation of efficacy data on 60y and older population using SARS-CoV-2 Vaccines

Immunisation Schedule. Influenza A (H5N1) update: "Bird flu spillover to mammals needs to be monitored closely, risk to humans currently low but we must prepare". (WHO). Respiratory Syncytial Virus (RSV) Bivalent Subgroups A and B Vaccine for Infants and Adults (due 2023). False Listing of RB51 as Approved Medicine for Brucellosis or Malta Fever. Streptococcus pneumoniae PCV20. R21/Matrix-M™ Malaria (Plasmodium falciparum) vaccine 77% efficacy (due 2023). Bivalent SARS-Cov-2. [I am very thankful to receive links, additions and corrections to update, and to remove any obsolete material herein if spotted. Anti-Covid-19, anti-MMR, anti-Gardasil, anti-poliovirus anti-vaxxer depopulating messages are both unwelcome and repulsive to me.] BREAKING NEWS: Vaccine Catastrophe - Veterinary Vaccine (Live-Attenuated Brucella abortus strain RB51) has incorrectly been indicated as an 'approved' prophylactic therapy for human vaccination against Brucellosis or Malta Fever (also variously known as ‘Mediterranean Fever’ and ‘Undulant Fever’). This error is totally inexcusable as this strain is extremely harmful when given to humans. Immunisation Schedule for Zaire Ebola virus for work where large bull (bovine) and buffalo herds are present (put together for the rescue and care insurers). Zaire Ebola contamination management in large herds of aforesaid large ruminants proves problematic with the biohazard suit that protect from the disease vectors as the animals respond aggressively to the human protective gear leading to panicking animals attacks, attempts of human butchery and animal rummage where people and properties can suddenly become threatened, as a health protection gives rise to animal threat by the rummaging animals trampling and horn attacking people in biohazard gear. The ring fencing experimental Zaire Ebola vaccines were not available at the time of this original plan instigated where the China-based organisation prepared an emergency quantitative easing (QE) cash programme, ‘helicopter drops of money’ as a mitigation strategy to persuade the food producers and food vendors to continue serving the general public against an infection risk during a major ebola epidemic - to prevent food industry's distribution and production collapses as the personnel might otherwise decide to stop working and to stay home so as to avoid infecting themselves by the dangerous pathogen (in this case a Zaire Ebola Virus). The above can lead to severe food shortages and ultimately potential starvation occurrence unless that epidemic had not subsided soon enough to prevent this secondary consequence from emerging. Because of similarity of early Zaire Ebola symptoms to other infectious illnesses at the early stages, the work undertaken in remote areas, the lead time in medical evacuations in case of illnesses, and the immense cost of privately-funded flying hospital dispatch to carry out a rescue operation, an exhaustive mutual exclusion prophylactic scheme was initiated to minimise unnecessary calls for such a flying hospital facility (remote medical service) from overseas. Reported BEXSERO to GlaxoSmithKline on an unlisted side effect of stealthy temperature rise (see 19/03/2020 version, page 7) to +42.3C / +108.1F with weakening of normal body temperature control like sweating and relative lack of sense of highly elevated body temperature able to cause heat stroke and other related damage to body. The immunisation schedule incorporates emergency authorisation Covid-19 immunisations and coronavirus vaccines that shortly complete their approval. Some of the Covid-19 immunisations likely vanish from marketplace as soon as the pandemic is over whereas some other vaccine designs may seek themselves second life as generic coronavirus immunisations. (The research field of coronaviruses is rapidly changing with these overlooked viruses also causing many common colds is brought into spotlight.) Almost all Covid-19 products have not been tested for concomitant use with many other immunisation products and therefore a reasonable space should be allowed between immunisations to avoid adverse effect risks. Because of this one ought to consider whether at current pandemic situation some immunisation products of lesser importance should be taken and whether it is better to defer them until situation clears (considering the ongoing infections with Covid-19 variants and especially in some remote regions where sequencing of the variants is very sparse as the protection to Covid-19 is very important). Because of above reason, this schedule is not currently geared for rapid deployment in tropics as too many uncertainties lie within which good protection against Covid-19 must prevail. Section on Covid-19 products is continually expiring due to evolving situation. Updates on Streptococcus pneumoniae PCV20. The latest version of the document supersedes all earlier versions that ought to be discarded and not used.

New Generation Vaccine Strategies against COVID-19

Immunisation Schedule. Influenza A (H5N1) update: "Bird flu spillover to mammals needs to be monitored closely, risk to humans currently low but we must prepare". (WHO). Respiratory Syncytial Virus (RSV) Bivalent Subgroups A and B Vaccine for Infants and Adults (due 2023). False Listing of RB51 as Approved Medicine for Brucellosis or Malta Fever. Streptococcus pneumoniae PCV20. R21/Matrix-M™ Malaria (Plasmodium falciparum) vaccine 77% efficacy (due 2023). Bivalent SARS-Cov-2. [I am very thankful to receive links, additions and corrections to update, and to remove any obsolete material herein if spotted. Anti-Covid-19, anti-MMR, anti-Gardasil, anti-poliovirus anti-vaxxer depopulating messages are both unwelcome and repulsive to me.] BREAKING NEWS: Vaccine Catastrophe - Veterinary Vaccine (Live-Attenuated Brucella abortus strain RB51) has incorrectly been indicated as an 'approved' prophylactic therapy for human vaccination against Brucellosis or Malta Fever (also variously known as ‘Mediterranean Fever’ and ‘Undulant Fever’). This error is totally inexcusable as this strain is extremely harmful when given to humans. Immunisation Schedule for Zaire Ebola virus for work where large bull (bovine) and buffalo herds are present (put together for the rescue and care insurers). Zaire Ebola contamination management in large herds of aforesaid large ruminants proves problematic with the biohazard suit that protect from the disease vectors as the animals respond aggressively to the human protective gear leading to panicking animals attacks, attempts of human butchery and animal rummage where people and properties can suddenly become threatened, as a health protection gives rise to animal threat by the rummaging animals trampling and horn attacking people in biohazard gear. The ring fencing experimental Zaire Ebola vaccines were not available at the time of this original plan instigated where the China-based organisation prepared an emergency quantitative easing (QE) cash programme, ‘helicopter drops of money’ as a mitigation strategy to persuade the food producers and food vendors to continue serving the general public against an infection risk during a major ebola epidemic - to prevent food industry's distribution and production collapses as the personnel might otherwise decide to stop working and to stay home so as to avoid infecting themselves by the dangerous pathogen (in this case a Zaire Ebola Virus). The above can lead to severe food shortages and ultimately potential starvation occurrence unless that epidemic had not subsided soon enough to prevent this secondary consequence from emerging. Because of similarity of early Zaire Ebola symptoms to other infectious illnesses at the early stages, the work undertaken in remote areas, the lead time in medical evacuations in case of illnesses, and the immense cost of privately-funded flying hospital dispatch to carry out a rescue operation, an exhaustive mutual exclusion prophylactic scheme was initiated to minimise unnecessary calls for such a flying hospital facility (remote medical service) from overseas. Reported BEXSERO to GlaxoSmithKline on an unlisted side effect of stealthy temperature rise (see 19/03/2020 version, page 7) to +42.3C / +108.1F with weakening of normal body temperature control like sweating and relative lack of sense of highly elevated body temperature able to cause heat stroke and other related damage to body. The immunisation schedule incorporates emergency authorisation Covid-19 immunisations and coronavirus vaccines that shortly complete their approval. Some of the Covid-19 immunisations likely vanish from marketplace as soon as the pandemic is over whereas some other vaccine designs may seek themselves second life as generic coronavirus immunisations. (The research field of coronaviruses is rapidly changing with these overlooked viruses also causing many common colds is brought into spotlight.) Almost all Covid-19 products have not been tested for concomitant use with many other immunisation products and therefore a reasonable space should be allowed between immunisations to avoid adverse effect risks. Because of this one ought to consider whether at current pandemic situation some immunisation products of lesser importance should be taken and whether it is better to defer them until situation clears (considering the ongoing infections with Covid-19 variants and especially in some remote regions where sequencing of the variants is very sparse as the protection to Covid-19 is very important). Because of above reason, this schedule is not currently geared for rapid deployment in tropics as too many uncertainties lie within which good protection against Covid-19 must prevail. Section on Covid-19 products is continually expiring due to evolving situation. Updates on Streptococcus pneumoniae PCV20. The latest version of the document supersedes all earlier versions that ought to be discarded and not used.

In search of a combined brucellosis and tuberculosis vaccine for cattle

Bovine brucellosis is caused by Brucella abortus. The bacterial pathogen causes economic losses because it induces abortion in cattle. Vaccination of calves with live B. abortus strain 19 induces a certain level of protection but induces persistent antibodies against cell envelope lipopolysaccharide that make it difficult to Distinguish Infected from Vaccinated Animals (DIVA). Live vaccine B. abortus strain RB51 was developed to eliminate such interfering antibodies and therefore, facilitate the differentiation of infected from vaccinated animals and help in the eradication of the disease. Vaccination with strain RB51 induces levels of protection similar to strain 19 but neither of the two vaccines give complete protection. We have been working to enhance protection induced by strain RB51 vaccine. Protective Brucella antigens can be over-expressed in strain RB51 by introducing a plasmid containing the leuB gene and the genes encoding such antigens. To avoid the expression of antibiotic resistance genes, we produced a leuB deficient strain RB51 and introduced a plasmid containing the leuB gene and the genes to be over-expressed. This new strain maintains the plasmid and has induced significantly high protection levels in mice. In addition, it allowed the construction of an RB51 vaccine strain able to express Mycobacterium bovis protective antigens so that the vaccine could protect against brucellosis and tuberculosis simultaneously.

Deteksi Molekuler Gen Penyandi Protein Virb11 pada Brucella abortus Isolat Lokal Asal Pinrang, NTT dan Strain Vaksin

Brucellosis in cattle is a disease caused by Brucella abortus due to the reduction in livestock population caused by abortion, stillbirth, weak birth, infertility and sterility. Brucella abortus has several potential virulence factors, i.e. virB11 gene that encodes VirB11 protein is an important virulence factor acts as an ATPase for assembling organelles when the bacteria replicate, helping to complete the bacterial cycle and agress to another cells. The aim of this study are to re-identification Brucella abortus and detect virB11 gene as encoding of B. abortus VirB11 protein in local isolates from Pinrang, NTT, strain vaccines S19 and RB51. The isolates Brucella abortus were re-cultured in Brucella agar base and re-identification is followed by microscopic with Gram staining and biochemical tested with urease, citrat, indol and TSIA test. virB11gene was detected with PCR method. The PCR result showed virB11 gene have DNA band 720 bp. virB11 gene are present in local isolates from Pinrang, NTT, strain vaccines S19 and RB51.