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Fulltext Sensitized-erythrocyte-lysis (SEL) test as an epidemiological tool for human leptospirosis serological surveys

Tan DS

Bull World Health Organ, 1969;40(6):899-902.
PMID: 5307602

Epidemiological studies of human leptospirosis have generally been limited to countries with specialized laboratories employing the microscopic-agglutination (MA) test. The sensitized-erythrocyte-lysis (SEL) test is much simpler for routine hospital laboratories to carry out and it has been found valuable in the diagnosis of human leptospirosis. This paper reports the results of studies of the SEL test as an epidemiological tool in serological surveys.The results showed that the significant SEL titre was 1:80 and that the sensitivity of the test depended possibly on the antigen preparation and the amount of complement used. Most of the SEL antibodies were found to persist at significant titres for about 1 year after active infection, but less than half persisted longer than that. The SEL test is therefore useful for detecting recent infections and for indicating that stability of leptospirosis in an area.The endemicity of leptospirosis in West Malaysia was confirmed by the SEL test, based on the employment of 1:80 as the significant titre.

Matched MeSH terms: Antibody Formation
Filarial antibodies and eosinophilia in human subjects in an endemic area

Wong MM, Guest MF

Trans R Soc Trop Med Hyg, 1969;63(6):796-800.
PMID: 5368008
Matched MeSH terms: Antibody Formation
Fulltext Induction of an Antibody Response against Plasmodium falciparum F2RIIEBA by Heterologous Prime-boost Immunisation

Suppian R, Nor NM

Trop Life Sci Res, 2013 Aug;24(1):9-18.
PMID: 24575238 MyJurnal

Heterologous prime-boost immunisation strategies can evoke powerful antibody responses and may be of value in developing an improved malaria vaccine. Herein, we show that an immunisation protocol that primes Balb/c mice with a recombinant Bacille Calmette-Guérin (rBCG) vaccine consisting of a plasmid encoding a synthetic fragment of the ESAT-6 epitope of Mycobacterium tuberculosis, the fragment 2 region II of erythrocyte-binding antigen (F2RIIEBA) and the three repeat sequences of the circumsporozoite protein (NANP)3 of Plasmodium falciparum before subsequently boosting the mice with either two doses of the rBCG clone or with a DNA vaccine expressing the native form of F2RIIEBA generating higher serum anti-F2RIIEBA antibody levels than an immunisation protocol that calls for a homologous prime-boost with two doses of rBCG. These results demonstrate the potential of DNA vaccination in boosting the antibody response to a recombinant vaccine expressing multiple epitopes.

Matched MeSH terms: Antibody Formation
Fulltext Development of solid - based paper strips for rapid diagnosis of Pseudorabies infection

Joon Tam Y, Mohd Lila MA, Bahaman AR

Trop Biomed, 2004 Dec;21(2):121-34.
PMID: 16493404

Pseudorabies (Aujeszky's disease) is an economically significant disease of swine known to cause central nervous disorders, respiratory disease, reproductive failure and mortality in infected pigs. In attempts to eradicate the disease from becoming endemic, early detection is important to prevent further economic losses and to allow for detection and removal of infected pigs in domestic herds. Thus, a rapid and sensitive technique is necessary for the detection of the virus. For rapid and simple examination, an immuno - chromatographic lateral - flow assay system based on immunologic recognition of specific pseudorabies virus antigen was developed by utilising, as signal generator, colloidal gold conjugated to secondary antibody to detect primary or sample antibody in the sera of pseudorabies infected animals. The pseudorabies virus used as a capture antigen in the test strip was first cultivated in VERO cell culture and then purified by sucrose gradient separation to produce the viral protein concentration of 3.8 mg/ml. The standard pseudorabies antigens reacted well with the hyperimmune serum (HIS). The antibody detection system is basically composed of colloidal gold - labelled antibodies fixed on a conjugate pad, and the complementary pseudorabies antigen immobilised onto a nitrocellulose membrane forming capture zone. If the target antibody is present in a specimen, the colloidal gold-labelled antibody will form a complex with the antibody sample. Subsequently, the formed complex will migrate to the capture zone and is then bound to the solid phase via antigen - antibody interaction. As a result, a signal marker is generated by the accumulation of colloidal gold for detection confirmation. The results obtained demonstrated that the optimum combination of pseudorabies antigen needed as the capture reagent and gold conjugate as secondary antibody recognition marker was at a concentration of 0.38mg/ml and at 1:10 dilution factor respectively. The sensitivity of the solid - based test strip towards pseudorabies antibodies was high with a detection limit of 1 to 10,000 - dilution factor. The specificity of the assay was 100% with no cross - reaction being observed with other sera or antibodies. Accurate reading time needed for confirmation of the assay can be completed in 5 min with a whole blood sample of 25 microl. The colloidal gold - labelled antibody is stable at room temperature for 6 months or more (data not shown). Findings from this study indicated that the solid - based test strip assay system provided high sensitivity and specificity for the detection of pseudorabies at low levels of antibody concentration. The assay was rapid, simple, cheap, and does not require any sophisticated equipment. Thus, the solid based test strip will be a useful serological screening technique or for rapid diagnosis of an infectious disease in target populations of animals characterised by heterogeneous antibody responses.

Matched MeSH terms: Antibody Formation
Biocompatible ionic liquids assisted transdermal co-delivery of antigenic protein and adjuvant for cancer immunotherapy

Chowdhury MR, Moshikur RM, Wakabayashi R, Moniruzzaman M, Goto M

Int J Pharm, 2021 May 15;601:120582.
PMID: 33872711 DOI: 10.1016/j.ijpharm.2021.120582

Human skin contains numerous antigen-presenting cells that are a potential target for several immune-based therapies, including vaccination and cancer immunotherapy. However, the outermost layer of the skin-the stratum corneum-acts as a major physical barrier against the permeation of antigens that have a molecular weight > 500 Da. In this study, an ionic liquid-assisted delivery system (ILDS) was developed, which enabled the successful transdermal delivery of an antigenic protein, ovalbumin (OVA), with a toll-like receptor agonist, imiquimod, as an adjuvant, to stimulate a specific immune response. Both the ionic liquids and ILDS were completely biocompatible for topical or transdermal application for therapeutic purposes. The skin permeation of the antigenic protein and adjuvant was found to be significantly enhanced because of the incorporation of a surface-active ionic liquid in the ILDS. An in vivo immunization study showed that there was a high level of OVA-specific IgG antibody production because of the enhanced permeation of the antigen and adjuvant across and into the skin. In a preclusive anticancer study, vaccination through ILDS showed stronger tumor-growth inhibition compared to control group. These results indicated that the ILDS could be a promising strategy for transdermal immunization as future therapeutics.

Matched MeSH terms: Antibody Formation
Some current trends in immunology

Nelson DS

Med J Malaya, 1969 Sep;24(1):3-11.
PMID: 4243841
Matched MeSH terms: Antibody Formation
Efficacy of intranasal administration of formalin-killed Pasteurella haemolytica A2 against intratracheal challenge in goats

Effendy AW, Zamri-Saad M, Puspa R, Rosiah S

Vet Rec, 1998 Apr 18;142(16):428-31.
PMID: 9595632

A trial was conducted to compare the efficacy of intranasal vaccination in protecting goats against pneumonic pasteurellosis with intramuscular vaccination using an oil adjuvant vaccine, and a combination of the two methods. Forty goats were divided into four equal groups. Group 1 was vaccinated twice intranasally with formalin-killed Pasteurella haemolytica A2, group 2 was vaccinated twice intramuscularly with an oil adjuvant vaccine containing P haemolytica A7, and group 3 was initially vaccinated intranasally with the formalin-killed P haemolytica A2 followed by intramuscular vaccination with the oil adjuvant vaccine. In each group the two vaccinations were carried out four weeks apart. Group 4 was the unvaccinated control group. All goats were challenged intratracheally with 4 ml of an inoculum containing live P haemolytica A2 at a concentration of 1.3 x 10(7) colony forming units/ml two weeks after the last vaccination and were killed 14 days after the challenge. Although group 2 showed the highest clinical score following the challenge, deaths were observed only in group 3. Three goats in group 1 had pneumonic lung lesions, compared with six goats in group 2 and all the goats in groups 3 and 4. The lung lesions in group 1 were significantly (P < 0.05) less severe than in groups 3 and 4. Similarly, the lesions in group 2 were markedly less severe than in groups 3 and 4, although the differences were not significant. The difference between the extent of the lung lesions in the goats in groups 1 and 2 was not significant. Antibody against P haemolytica A2 in group 1 reached peak levels and was significantly (P < 0.01) higher than in the control group one week after the second vaccination, before declining.

Matched MeSH terms: Antibody Formation
Fulltext A randomized controlled phase 2 trial of the blood stage AMA1-C1/Alhydrogel malaria vaccine in children in Mali

Sagara I, Dicko A, Ellis RD, Fay MP, Diawara SI, Assadou MH, et al.

Vaccine, 2009 May 18;27(23):3090-8.
PMID: 19428923 DOI: 10.1016/j.vaccine.2009.03.014

A double blind, randomized, controlled Phase 2 clinical trial was conducted to assess the safety, immunogenicity, and biologic impact of the vaccine candidate Apical Membrane Antigen 1-Combination 1 (AMA1-C1), adjuvanted with Alhydrogel. Participants were healthy children 2-3 years old living in or near the village of Bancoumana, Mali. A total of 300 children received either the study vaccine or the comparator. No impact of vaccination was seen on the primary endpoint, the frequency of parasitemia measured as episodes >3000/microL/day at risk. There was a negative impact of vaccination on the hemoglobin level during clinical malaria, and mean incidence of hemoglobin <8.5 g/dL, in the direction of lower hemoglobin in the children who received AMA1-C1, although these differences were not significant after correction for multiple tests. These differences were not seen in the second year of transmission.

Matched MeSH terms: Antibody Formation/drug effects
Appraisal of immunomodulatory potential of Spirulina fusiformis: an in vivo and in vitro study

Rasool M, Sabina EP

J Nat Med, 2009 Apr;63(2):169-75.
PMID: 19093070 DOI: 10.1007/s11418-008-0308-2

In recent years, Spirulina has gained more and more attention from medical scientists as a nutraceutical and a source of potential pharmaceuticals. The present study was conducted to elucidate the immunomodulatory effect of Spirulina fusiformis (a cyanobacterium of the family Oscillatoriaceae) in vivo and in vitro. The in vivo effect of S. fusiformis (400 or 800 mg/kg body wt.) on humoral immune response, cell-mediated immune response and tumour necrosis factor alpha was investigated in mice. We also evaluated the effect of S. fusiformis (50 or 100 microg/ml) in vitro on mitogen (phytohaemagglutinin)-induced T lymphocyte proliferation in heparinized human peripheral blood. For comparison, dexamethasone was used as a standard. In mice, S. fusiformis (400 or 800 mg/kg body wt.) administration significantly inhibited the humoral immune response, cell-mediated immune response (delayed-type hypersensitivity reaction (DTH)) and tumour necrosis factor alpha in a dose-dependent manner. In vitro, S. fusiformis (50 or 100 microg/ml) decreased the mitogen (phytohaemagglutinin)-induced T lymphocyte proliferation in a concentration-dependent manner when compared with control cells. These observations clearly suggest that S. fusiformis has a remarkable immunosuppressive effect, which provides a scientific validation for the popular use of this drug, and helped us in further work on investigating its complete mechanism of action.

Matched MeSH terms: Antibody Formation/drug effects
Fulltext IgM in human immunity to Plasmodium falciparum malaria

Boyle MJ, Chan JA, Handayuni I, Reiling L, Feng G, Hilton A, et al.

Sci Adv, 2019 09;5(9):eaax4489.
PMID: 31579826 DOI: 10.1126/sciadv.aax4489

Most studies on human immunity to malaria have focused on the roles of immunoglobulin G (IgG), whereas the roles of IgM remain undefined. Analyzing multiple human cohorts to assess the dynamics of malaria-specific IgM during experimentally induced and naturally acquired malaria, we identified IgM activity against blood-stage parasites. We found that merozoite-specific IgM appears rapidly in Plasmodium falciparum infection and is prominent during malaria in children and adults with lifetime exposure, together with IgG. Unexpectedly, IgM persisted for extended periods of time; we found no difference in decay of merozoite-specific IgM over time compared to that of IgG. IgM blocked merozoite invasion of red blood cells in a complement-dependent manner. IgM was also associated with significantly reduced risk of clinical malaria in a longitudinal cohort of children. These findings suggest that merozoite-specific IgM is an important functional and long-lived antibody response targeting blood-stage malaria parasites that contributes to malaria immunity.

Matched MeSH terms: Antibody Formation/immunology
The full-length clone of cucumber green mottle mosaic virus and its application as an expression system for Hepatitis B surface antigen

Ooi A, Tan S, Mohamed R, Rahman NA, Othman RY

J Biotechnol, 2006 Feb 24;121(4):471-81.
PMID: 16271415

A cucumber green mosaic mottle virus (CGMMV) full-length clone was developed for the expression of Hepatitis B surface antigen (HBsAg). The expression of the surface displayed HBsAg by the chimeric virus was confirmed through a double antibody sandwich ELISA. Assessment of the coat protein composition of the chimeric virus particles by SDS-PAGE analysis showed that 50% of the coat proteins were fused to the HBsAg. Biological activity of the expressed HBsAg was assessed through the stimulation of in vitro antibody production by cultured peripheral blood mononuclear cells (PBMC). PBMC that were cultured in the presence of the chimeric virus showed up to an approximately three-fold increase in the level of anti HBsAg immunoglobulin thus suggesting the possible use of this new chimeric virus as an effective Hepatitis B vaccine.

Matched MeSH terms: Antibody Formation/immunology
Fulltext Yellow fever vaccination in Malaya by subcutaneous injection and multiple puncture. Haemagglutinin-inhibiting antibody responses in persons with and without pre-existing antibody

Gordon Smith CE, McMahon DA, Turner LH

Bull World Health Organ, 1963;29:75-80.
PMID: 14043754

In view of the risk of introduction of yellow fever into South-East Asia, comparative studies have been made of yellow fever vaccination in Malayan volunteers with a high prevalence of antibody to related viruses and in volunteers without related antibody. In a previous paper the neutralizing antibody responses of these volunteers were reported. The present paper describes the haemagglutinin-inhibiting (HI) antibody responses of the same groups of volunteers and discusses the relationship of these responses to the neutralizing antibody responses.The HI responses to yellow fever following vaccination closely paralleled the neutralizing antibody responses whether vaccination was subcutaneous or by multiple puncture. Volunteers with a high level of YF HI antibody due to infection with other group B viruses were found to be less likely to show a significant YF HI response than those without antibody. 90% of HI responses could be detected by the 21st day after vaccination.As with neutralizing antibody responses, volunteers given vaccine doses of 50-500 mouse intracerebral LD(50) subcutaneously gave greater responses than those given higher doses.

Matched MeSH terms: Antibody Formation*
Fulltext An Inactivated Antibiotic-Exposed Whole-Cell Vaccine Enhances Bactericidal Activities Against Multidrug-Resistant Acinetobacter baumannii

Shu MH, MatRahim N, NorAmdan N, Pang SP, Hashim SH, Phoon WH, et al.

Sci Rep, 2016;6:22332.
PMID: 26923424 DOI: 10.1038/srep22332

Vaccination may be an alternative treatment for infection with multidrug-resistance (MDR) Acinetobacter baumannii. The study reported here evaluated the bactericidal antibody responses following immunization of mice using an inactivated whole-cell vaccine derived from antibiotic-exposed MDR A. baumannii (I-M28-47-114). Mice inoculated with I-M28-47 (non-antibiotic-exposed control) and I-M28-47-114 showed a high IgG antibody response by day 5 post-inoculation. Sera from mice inoculated with I-M28-47-114 collected on day 30 resulted in 80.7 ± 12.0% complement-mediated bacteriolysis in vitro of the test MDR A. baumannii treated with imipenem, which was a higher level of bacteriolysis over sera from mice inoculated with I-M28-47. Macrophage-like U937 cells eliminated 49.3 ± 11.6% of the test MDR A. baumannii treated with imipenem when opsonized with sera from mice inoculated with I-M28-47-114, which was a higher level of elimination than observed for test MDR A. baumannii opsonized with sera from mice inoculated with I-M28-47. These results suggest that vaccination with I-M28-47-114 stimulated antibody responses capable of mounting high bactericidal killing of MDR A. baumannii. Therefore, the inactivated antibiotic-exposed whole-cell vaccine (I-M28-47-114) has potential for development as a candidate vaccine for broad clearance and protection against MDR A. baumannii infections.

Matched MeSH terms: Antibody Formation
Fulltext Immunogenicity of a plasma-derived hepatitis B vaccine in children and adults

Sinniah M, Halimah M, Krishnamurthy T, Lye MS, Choo CH, Shamsiah I

Med J Malaysia, 1994 Dec;49(4):336-40.
PMID: 7674968

Immunisation of health care workers and staff working in laboratory and hospital settings has been implemented since 1988. However due to the high cost of currently available HBV vaccine, many health personnel outside the Ministry of Health are not being immunised. This study sought to determine the immunogenicity of three doses of a low cost plasma-derived Korean HBV vaccine on employees of an institute for mentally handicapped and their spouses and children. We found that the Hepatitis B Vaccine-KGCC to be safe and immunogenic. The response to 10 mcg and 20 mcg Hepatitis B Vaccine-KGCC after third dose was good with 100% seroconversion.

Matched MeSH terms: Antibody Formation
Fulltext Efficacy of Whole Cell Inactivated Vibrio harveyi Vaccine against Vibriosis in a Marine Red Hybrid Tilapia (Oreochromis niloticus × O. mossambicus) Model

Abu Nor N, Zamri-Saad M, Md Yasin IS, Salleh A, Mustaffa-Kamal F, Matori MF, et al.

Vaccines (Basel), 2020 Dec 04;8(4).
PMID: 33291587 DOI: 10.3390/vaccines8040734

Vibrio harveyi causes vibriosis in various commercial marine fish species. The infection leads to significant economic losses for aquaculture farms, and vaccination is an alternative approach for the prevention and control of fish diseases for aquaculture sustainability. This study describes the use of formalin-killed Vibrio harveyi (FKVh) strain Vh1 as a vaccine candidate to stimulate innate and adaptive immunities against vibriosis in a marine red hybrid tilapia model. Tilapia are fast growing; cheap; resistant to diseases; and tolerant to adverse environmental conditions of fresh water, brackish water, and marine water and because of these advantages, marine red hybrid tilapia is a suitable candidate as a model to study fish diseases and vaccinations against vibriosis. A total of 180 healthy red hybrid tilapias were gradually adapted to the marine environment before being divided into two groups, with 90 fish in each group and were kept in triplicate with 30 fish per tank. Group 1 was vaccinated intraperitoneally with 100 µL of FKVh on week 0, and a booster dose was similarly administered on week 2. Group 2 was similarly injected with PBS. Skin mucus, serum, and gut lavage were collected weekly for enzyme-linked immunosorbent assay (ELISA) and a lysozyme activity assay from a total of 30 fish of each group. On week 4, the remaining 60 fish of Groups 1 and 2 were challenged with 108 cfu/fish of live Vibrio harveyi. The clinical signs were monitored while the survival rate was recorded for 48 h post-challenge. Vaccination with FKVh resulted in a significantly (p < 0.05) higher rate of survival (87%) compared to the control (20%). The IgM antibody titer and lysozyme activities of Group 1 were significantly (p < 0.05) higher than the unvaccinated Groups 2 in most weeks throughout the experiment. Therefore, the intraperitoneal exposure of marine red hybrid tilapia to killed V. harveyi enhanced the resistance and antibody response of the fish against vibriosis.

Matched MeSH terms: Antibody Formation
Childhood rhinitis is predominantly associated with mite allergens

Yadav, M., Harnam, S.

Malaysian Journal of Child Health, 1998;10(1):19-27.
MyJurnal

The total and allergen-specific IgE response of patients with rhinitis, rhinoconjunctivities, rhinitis with asthma and rhinitis with dermatitis was analyzed to a panel of twelve high risk airborne and food allergens. It has been found that this panel will detect 96 percent of the allergen-causing diseases in children. It was found that 26 (76%) of the 34 young patients had a family history for atopy suggesting a high frequency of inheritance of allergic disorders. Elevated total IgE was found in most patients with allergic disease. Positive IgE antibody response to two species of Dermatophagoides mite-allergens was found in 7/12 (58%) patients with rhinitis, 11/11 (100%) patients with rhinoconjunctivitis, 7/9 (78%) cases ofrhinitis with asthma and 3/3 (100%) cases of rhinitis with dermatitis. Some of the patients also responded to food allergens. Food allergy was noted in 4/12 (33%) cases of rhinitis, 11/11 (100%) cases of rhinoconjunctivitis, 4/9 (44%) cases of rhinitis with asthma and 1/3 (33%) cases of rhinitis with dermatitis. Patients with rhinoconjunctivitis who tested positive at high titres for mites invariably had enhanced response for cockroaches, shrimps and crabs suggesting invertebrate antigen cross-reactivity. A few patients however, did not show this type of cross-reactivity although they had high titres of anti-mite IgE antibodies indicating that they responded to non cross-reacting allergen epitopes. Response to multiple allergens appears to be a common feature of most patients with respiratory or skin allergic diseases. The prevalence of multiple target-organ allergy to wide variety offood and environmental allergens complicates the long term management ofpatients with such allergic disorders.

Matched MeSH terms: Antibody Formation
Fulltext Antibody-dependent cellular phagocytosis of tropomyosin receptor kinase C (TrkC) expressing cancer cells for targeted immunotherapy

Lai PS, Usama SM, Kiew LV, Lee HB, Chung LY, Burgess K, et al.

Cancer Immunol Immunother, 2022 Sep;71(9):2099-2108.
PMID: 35032175 DOI: 10.1007/s00262-022-03147-y

Conventional cancer therapies such as chemotherapy are non-selective and induce immune system anergy, which lead to serious side effects and tumor relapse. It is a challenge to prime the body's immune system in the cancer-bearing subject to produce cancer antigen-targeting antibodies, as most tumor-associated antigens are expressed abundantly in cancer cells and some of normal cells. This study illustrates how hapten-based pre-immunization (for anti-hapten antibodies production) combined with cancer receptor labeling with hapten antigen constructs can elicit antibody-dependent cellular phagocytosis (ADCP). Thus, the hapten antigen 2,4-dinitrophenol (DNP) was covalently combined with a cancer receptor-binding dipeptide (IYIY) to form a dipeptide-hapten construct (IYIY-DNP, MW = 1322.33) that targets the tropomyosin receptor kinase C (TrkC)-expressed on the surface of metastatic cancer cells. IYIY-DNP facilitated selective association of RAW264.7 macrophages to the TrkC expressing 4T1 cancer cells in vitro, forming cell aggregates in the presence of anti-DNP antibodies, suggesting initiation of anti-DNP antibody-dependent cancer cell recognition of macrophages by the IYIY-DNP. In in vivo, IYIY-DNP at 10 mg/kg suppressed growth of 4T1 tumors in DNP-immunized BALB/c mice by 45% (p

Matched MeSH terms: Antibody Formation
Immunomodulation by morphine and marijuana

Yahya MD, Watson RR

Life Sci, 1987 Dec 07;41(23):2503-10.
PMID: 2824957

The immunomodulatory effects of morphine and the active components of marijuana, particularly tetrahydrocannabinol, on various aspects of the host immune parameters include alterations in humoral, cell-mediated and innate immunity. Most studies have shown immunosuppressive effects due to use of these abused substances, although there are reports that they may not produce any deleterious effect and may even enhance some aspects of host immunity. They reduce resistance to cancer growth and microbial pathogens in animals.

Matched MeSH terms: Antibody Formation/drug effects*
Fulltext Immunogenicity and protective efficacy of a live, oral cholera vaccine formulation stored outside-the-cold-chain for 140 days

Xian TH, Sinniah K, Yean CY, Krishnamoorthy V, Bahari MB, Ravichandran M, et al.

BMC Immunol, 2020 05 25;21(1):29.
PMID: 32450807 DOI: 10.1186/s12865-020-00360-1

BACKGROUND: Cholera, an acute watery diarrhoeal disease caused by Vibrio cholerae serogroup O1 and O139 across the continents. Replacing the existing WHO licensed killed multiple-dose oral cholera vaccines that demand 'cold chain supply' at 2-8 °C with a live, single-dose and cold chain-free vaccine would relieve the significant bottlenecks and cost determinants in cholera vaccination campaigns. In this direction, a prototype cold chain-free live attenuated cholera vaccine formulation (LACV) was developed against the toxigenic wild-type (WT) V. cholerae O139 serogroup. LACV was found stable and retained its viability (5 × 106 CFU/mL), purity and potency at room temperature (25 °C ± 2 °C, and 60% ± 5% relative humidity) for 140 days in contrast to all the existing WHO licensed cold-chain supply (2-8 °C) dependent killed oral cholera vaccines.
RESULTS: The LACV was evaluated for its colonization potential, reactogenicity, immunogenicity and protective efficacy in animal models after its storage at room temperature for 140 days. In suckling mice colonization assay, the LACV recorded the highest recovery of (7.2 × 107 CFU/mL) compared to those of unformulated VCUSM14P (5.6 × 107 CFU/mL) and the WT O139 strain (3.5 × 107 CFU/mL). The LACV showed no reactogenicity even at an inoculation dose of 104-106 CFU/mL in a rabbit ileal loop model. The rabbits vaccinated with the LACV or unformulated VCUSM14P survived a challenge with WT O139 and showed no signs of diarrhoea or death in the reversible intestinal tie adult rabbit diarrhoea (RITARD) model. Vaccinated rabbits recorded a 275-fold increase in anti-CT IgG and a 15-fold increase in anti-CT IgA antibodies compared to those of rabbits vaccinated with unformulated VCUSM14P. Vibriocidal antibodies were increased by 31-fold with the LACV and 14-fold with unformulated VCUSM14P.
CONCLUSION: The vaccine formulation mimics a natural infection, is non-reactogenic and highly immunogenic in vivo and protects animals from lethal wild-type V. cholerae O139 challenge. The single dose LACV formulation was found to be stable at room temperature (25 ± 2 °C) for 140 days and it would result in significant cost savings during mass cholera vaccination campaigns.

Matched MeSH terms: Antibody Formation/immunology*
Fulltext Antibody Responses to Helicobacter pylori and Risk of Developing Colorectal Cancer in a European Cohort

Butt J, Jenab M, Pawlita M, Tjønneland A, Kyrø C, Boutron-Ruault MC, et al.

Cancer Epidemiol Biomarkers Prev, 2020 Jul;29(7):1475-1481.
PMID: 32332031 DOI: 10.1158/1055-9965.EPI-19-1545

BACKGROUND: While Helicobacter pylori (H. pylori) is the major cause of gastric cancer, it has also been suggested to be involved in colorectal cancer development. However, prospective studies addressing H. pylori and colorectal cancer are sparse and inconclusive. We assessed the association of antibody responses to H. pylori proteins with colorectal cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort.
METHODS: We applied H. pylori multiplex serology to measure antibody responses to 13 H. pylori proteins in prediagnostic serum samples from 485 colorectal cancer cases and 485 matched controls nested within the EPIC study. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using multivariable conditional logistic regression to estimate the association of H. pylori overall and protein-specific seropositivity with odds of developing colorectal cancer.
RESULTS: Fifty-one percent of colorectal cancer cases were H. pylori seropositive compared with 44% of controls, resulting in an OR of 1.36 (95% CI, 1.00-1.85). Among the 13 individual H. pylori proteins, the association was driven mostly by seropositivity to Helicobacter cysteine-rich protein C (HcpC; OR: 1.66; 95% CI, 1.19-2.30) and Vacuolating cytotoxin A (VacA) (OR: 1.34; 95% CI, 0.99-1.82), the latter being nonstatistically significant only in the fully adjusted model.
CONCLUSIONS: In this prospective multicenter European study, antibody responses to H. pylori proteins, specifically HcpC and VacA, were associated with an increased risk of developing colorectal cancer.
IMPACT: Biological mechanisms for a potential causal role of H. pylori in colorectal carcinogenesis need to be elucidated, and subsequently whether H. pylori eradication may decrease colorectal cancer incidence.

Matched MeSH terms: Antibody Formation/genetics*

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