Serum Levels Of Specific Antibodies Research Articles

Edwardsiella tarda Outer Membrane Protein C: An Immunogenic Protein Induces Highly Protective Effects in Flounder (Paralichthys olivaceus) against Edwardsiellosis.

Outer membrane protein C of Edwardsiella tarda is a major cell surface antigen and it was identified to be an immunogenic protein by Western blot using flounder (Paralichthys olivaceus) anti-recombinant OmpC (rOmpC), and anti-E. tarda antibodies. rOmpC tested the immune protective effect against E. tarda challenge in a flounder model and produced a relative percentage of survival rate of 85%. The immune response of flounder induced by rOmpC was investigated, and the results showed that: (1) the levels of specific serum antibodies induced by rOmpC were significantly higher than the control group after the second week after immunization, and the peak level occurred at week five after immunization; (2) rOmpC could induce the proliferation of sIg+ lymphocytes, and the peak levels of sIg+ lymphocytes in blood, spleen, and pronephros occurred at 4–5 weeks after immunization; and (3) the MHCIIα, CD4-1, IL-1β, IL-6 and TNF-α genes were significantly induced after being injected with rOmpC. Taken together, these results demonstrated that rOmpC could evoke highly protective effects against E. tarda challenge and induce strong innate immune response and humoral immune response of flounder, which indicated that OmpC was a promising vaccine candidate against E. tarda infection.

Unique dose-dependent effects of the human pregnancy hormone estriol on the ratio of blood IgM to IgG in female mice.

The present study aimed to investigate the dose-dependent modulating effect of estriol (E3), an estrogen predominantly produced during human pregnancy, on antigen‑induced production of specific antibodies in female BALB/c mice. The animals were immunized either with bovine serum albumin (BSA) or the pneumococcal polysaccharide serotype-14 (PPS-14), and the levels of specific serum antibodies were determined using ELISA kits. E3 was found to have very different effects on antigen-induced production of specific antibodies in animals immunized with these two antigens. While E3 stimulated the production of PPS-14-specific antibodies, it suppressed the production of BSA-specific antibodies. The results also demonstrated that the modulating effect of E3 on the production of antigen‑specific antibodies depends on the dose of E3 used. For BSA‑induced antibody production, E3 had a dose‑dependent inhibitory effect, whereas for PPS‑14‑specific antibody (Ab) production, E3 exerted the strongest stimulation at a lower dose, and produced less stimulation at higher doses. E3 caused thymus atrophy in animals immunized with either PPS‑14 or BSA, but only induced spleen atrophy in BSA‑injected mice. These observations suggest that E3 increases the ability of a pregnant female to avoid bacterial infections while decreasing the incidence of autoimmune responses against circulating components from either the fetus or pregnant female.

Previous Exposure to the Fish Parasite Anisakis as a Potential Risk Factor for Gastric or Colon Adenocarcinoma.

Anisakiasis is a global disease caused by consumption of raw or lightly cooked fish contaminated with L3 Anisakis spp. larvae. High rates of parasitization of fish worldwide make Anisakis a serious health hazard. In fact, anisakiasis is a growing disease in countries such as Spain, Italy, and Japan, where consumption of raw/marinated fish is high.Some parasitic infections have been recognized as a causative factor for human cancer. Suggested mechanisms include chronic inflammation elicited by the parasite, and a possible tumorigenic effect from certain parasitic secretions.Anisakis can produce persistent local inflammation and granuloma, and larvae have been incidentally found in gastrointestinal (GI) tumors. Our aim was to discover possible differences in the prevalence of unnoticed or asymptomatic previous Anisakis infection in GI cancer patients compared with healthy individuals. Serum levels of specific antibodies against Anisakis antigens were used as a reliable marker of previous contact with their larvae.Ninety-four participants without a previous history of Anisakis infection were prospectively allocated into 1 of 2 groups: 47 patients with GI cancer and 47 controls. Specific IgE, IgA1, and IgG1 against the Anisakis recombinant antigens Ani s 1, Ani s 5, Ani s 9, and Ani s 10 were determined by an ELISA assay.The ratio of positivity to sIgA1, rAni s 1, or rAni s 5 was significantly higher in the cancer patients than in the controls (38.30% vs 6.38%, P < 0.001) and (42.55% vs 10.64%, P < 0.001, respectively). When disaggregated by type of tumor, the patients with gastric cancer showed a higher proportion of positive results for sIgA1 to rAni s 1 (P < 0.001), whereas a higher proportion of colon cancer patients were shown to be positive for sIgA1 to both rAni s 1 (P < 0.05) and rAni s 5 (P < 0.01).Earlier Anisakis infection might be a risk factor for the development of stomach or colon cancer.

Immunization routes in cattle impact the levels and neutralizing capacity of antibodies induced against S. aureus immune evasion proteins.

Vaccines against S. aureus bovine mastitis are scarce and show limited protection only. All currently available vaccines are applied via the parenteral (usually intramuscular) route. It is unknown, however, whether this route is the most suitable to specifically increase intramammary immunity to combat S. aureus at the site of infection. Hence, in the present study, immunization via mucosal (intranasal; IN), intramuscular (triangle of the neck; IM), intramammary (IMM) and subcutaneous (suspensory ligament; SC) routes were analyzed for their effects on the quantity of the antibody responses in serum and milk as well as the neutralizing capacity of the antibodies within serum. The experimental vaccine comprised the recombinant S. aureus immune evasion proteins extracellular fibrinogen-binding protein (Efb) and the leukotoxin subunit LukM in an oil-in-water adjuvant combined with a hydrogel and alginate. The highest titer increases for both Efb and LukM specific IgG1 and IgG2 antibody levels in serum and milk were observed following SC/SC immunizations. Furthermore, the harmful effects of Efb and leukotoxin LukMF’ on host-defense were neutralized by serum antibodies in a route-dependent manner. SC/SC immunization resulted in a significant increase in the neutralizing capacity of serum antibodies towards Efb and LukMF’, shown by increased phagocytosis of S. aureus and increased viability of bovine leukocytes. Therefore, a SC immunization route should be considered when aiming to optimize humoral immunity against S. aureus mastitis in cattle.Electronic supplementary materialThe online version of this article (doi:10.1186/s13567-015-0243-7) contains supplementary material, which is available to authorized users.

Serum antibody responses in pigs trickle-infected with Ascaris and Trichuris: Heritabilities and associations with parasitological findings

A humoral immune response following helminth infection in pigs is well documented. However, it has been difficult to confirm the existence of antibody mediated resistance against the large roundworm, Ascaris suum, and whipworm, Trichuris suis, in experimental settings by correlating worm burdens or egg excretion with specific antibody levels. We set out to investigate the association between worm load and T. suis and A. suum specific serum antibody levels (IgG1, IgG2 and IgA) against excretory-secretory products of adults and third stage larvae, respectively, measured at 0, 7 and 14 weeks p.i. in a trickle-infected F1-resource-population of crossbred pigs (n=195). Furthermore, we wanted to determine the heritability of these antibody isotypes during the course of infection. Most pigs remained infected with A. suum throughout the experiment while they expelled T. suis between 7 and 14 weeks post infection (p.i.). Parasite specific IgG1 and IgA were significantly (P<0.001) elevated after 7 and 14 weeks of infection, whereas parasite specific IgG2 levels only changed slightly at 14 weeks p.i.. However, the observed association between specific antibody isotype levels and faecal egg counts and macroscopic worm load was weak. The relative heritabilities of the different parasite specific isotypes were assessed and resulted in significant heritability estimates for parasite specific IgG1 and IgA. The highest heritabilities were found for A. suum specific IgG1 (h2=0.41 and 0.46 at 7 and 14 weeks p.i., respectively). Thus, the present study demonstrates that host genetic factors influence the IgG1 and IgA antibody isotype responses specific to two of the most common gastrointestinal nematodes of swine whereas specific antibody levels were poorly associated with egg excretion and the presence of macroscopic worms.

Evaluation of candidal colonization and specific humoral responses against Candida albicans in patients with psoriasis.

Psoriasis is an inflammatory skin disease that can considerably affect a patient's quality of life. Environmental and genetic factors, as well as superantigens and toxins from Candida species, may play various roles in the exacerbation and persistence of psoriasis. In the present study, we evaluated candidal colonization and specific humoral responses against Candida albicans in patients with psoriasis. A total of 100 patients with psoriasis vulgaris and 50 healthy control individuals were enrolled in the study. Skin and oral specimens from all participants were cultured on CHROMagar Candida medium. Isolated yeast-like fungi were identified using the sequence of the D1/D2 domain of the 26S rRNA gene. Enzyme-linked immunosorbent assays (ELISAs) were used to detect immunoglobulin M (IgM), IgA, and IgG antibodies against C. albicans in sera of patients and healthy individuals. Candida species were isolated from the skin of 15% of patients and 4% of controls and from oral specimens of 60% of patients and 20% of controls. There was a significant difference in candidal colonization between patients and controls (P < 0.05). Serum IgM, IgA, and IgG levels against C. albicans were significantly lower in patients with psoriasis than in controls (P < 0.05). There was no significant association between serum levels of specific antibodies against C. albicans or the frequency of candidal colonization with the clinical severity of the disease (P > 0.05). The results of the present study show a higher rate of candidal colonization in patients with psoriasis in comparison with controls and a reduction in humoral immune responses in patients.

Immune responses result in misdiagnosis of Schistosoma japonicum by immunodiagnosis kits in egg-positive patients living in a low schistosomiasis transmission area of China.

BackgroundIn recent field surveys, we failed to detect the presence of specific antibody against Schistosoma japonicum in some egg-positive patients by commonly used immunodiagnostic kits. To find out whether low levels of specific antibody truly exist among egg-positive individuals and elucidate the underlying immune mechanisms, we carried out a cross-sectional epidemiologic study in a S. japonicum low transmission endemic area of Poyang Lake region, China and compared the humoral and cellular immune characteristics between S. japonicum high and low antibody responders.MethodsKato–Katz thick smear assay was used to determine the schistosomiasis status of 3,384 participants residing in two Poyang Lake region villages, Jiangxi, China. Among the 142 stool egg-positive participants, we identified low and high S. japonicum antibody responders with soluble egg antigen (SEA) and adult worm antigen (AWA) specific IgG levels by adopting ROC curve analysis. To compare the humoral and cellular immune responses between high and low S. japonicum antibody responders, serum specific antibody levels as well as the percentage of T lymphocyte subpopulation in PMBC, and cell stimulated cytokines (IFN- gamma and interlukin-10) were detected.ResultsEight S. japonicum egg-positive participants were defined as low antibody responders. Although the percentage of CD3+T cells in low responders was slightly higher and the percentage of CD4+ T cells, CD8+ T cells, the ratio of CD4+/CD8+ and CD4+ CD25+ Treg cells were lower than those in high responders, the differences between the two groups were not significant (P > 0.05). AWA -stimulated interlukin-10 level was significantly higher in high responders, while other cytokines did not show differences between two groups. For antibody profiles, except AWA specific IgA, significant differences of each antibody isotype between low and high responders were detected (P < 0.05).ConclusionsOur study confirmed that there are S. japonicum antibody low responders among schistosome egg-positive residents in S. japonicum low-transmission areas in China. Thus, mis-diagnosis using immune-diagnosis kits do exist. Significant differences of responding antibody levels between low and high responders were detected, while no major cellular response changes were observed.

Evaluation of nanoparticle-encapsulated outer membrane proteins for the control of Campylobacter jejuni colonization in chickens

Numerous vaccination strategies have been evaluated to develop effective vaccines against Campylobacter jejuni colonization in poultry but with limited success. The following experiments were conducted to investigate the effect of biodegradable and biocompatible poly (lactide-co-glycolide) nanoparticle (NP) encapsulated outer membrane proteins (OMP) of C. jejuni. Chickens were vaccinated with different routes [subcutaneous (s/c) or oral] and doses (25, 125, or 250 µg) of candidate nanoparticle vaccine with appropriate control groups. Serum and cloacal fecal samples were taken at regular intervals of time, and the birds were euthanized 7 d postchallenge with C. jejuni. The results were interpreted based on anti-OMP immunoglobulin response in chicken and intestinal colonization of C. jejuni. The C. jejuni colonization in cecal and cloacal contents at 7 d postchallenge was below the detection limit in the s/c vaccinated groups, but the other groups demonstrated varying degrees of colonization. The serum IgA was higher in the group vaccinated s/c with OMP only compared with the rest of the groups. The serum- and fecal-IgY titers were consistently higher in the s/c vaccinated groups (with or without NP) than the rest of the groups. Elevated levels of OMP specific serum antibodies correlated with below the limit of detection levels of Campylobacter colonization in broiler chickens receiving 125 μg of OMP alone and the OMP+NP vaccine s/c. In conclusion, the s/c route of vaccination with or without NP encapsulated OMP of C. jejuni may serve as a candidate vaccine for control of C. jejuni colonization in chickens.

Comparison of Different Assays To Assess Human Papillomavirus (HPV) Type 16- and 18-Specific Antibodies after HPV Infection and Vaccination

We compared the measurement of human papillomavirus (HPV)-specific serum antibody levels with the virus-like-particle multiplex immunoassay (VLP-MIA), competitive Luminex immunoassay (cLIA), and glutathione S-transferase (GST) L1-based MIA. Using a large panel of serum samples, these assays showed mutually good correlations for both naturally induced and vaccine-derived HPV-specific antibody levels. However, an adaptation of the GST L1-based MIA resulted in an improved correlation with both cLIA and VLP-MIA.

SAT0043 Impaired B cell immunity in IL-27R knock-out mice in collagen induced arthritis

BackgroundCollagen induced arthritis (CIA), a mouse model for rheumatoid arthritis, is both B cell and T helper (Th) 17 cell mediated. Interleukin 27 receptor (IL27R) signaling upregulates IL12 receptor expression...

Fast and easy access to the overall B cell repertoire using the Blood B Booster® system (P3360)

Abstract Overall B repertoire analysis usually requires extensive molecular analysis of immunoglobulin genes. Determination of serum levels of specific antibodies by ELISA is restricted to “non steady-state” cases such as following vaccination, bacterial or viral infections. Dendritics has developed the Blood B Booster® system, a powerful B cell immortalization tool based on stimulation through CD40 and immortalization with Epstein-Barr virus. Briefly, the Blood B Booster® system is intended to generate B cell oligoclones representative of the overall B cell population. Here, using blood sample isolated from a healthy donor, we demonstrated that natural autoantibodies against various cytokines are detected at variable frequencies by ELISA in the supernatants of B cell oligoclones after 28 days of culture. Furthermore, we showed that Blood B Booster® is a suitable readout system to evaluate the effects of a given monoclonal antibody on B cell growth and/or Ig secretion. Finally, extension of the Blood B Booster® system to animal species allowed us to perform comparative studies between canine and human humoral responses against a candidate vaccine. In conclusion, analysis of the natural autoantibody repertoire, of the antibody responses against therapeutic agents (candidate vaccine, therapeutic mAbs) and human/animal comparative studies will be facilitated by the Blood B Booster® system which is shown here as an essential tool giving a fast and easy access to the overall B repertoire.

Efficacy of a DNA Vaccine Carrying Eimeria maxima Gam56 Antigen Gene against Coccidiosis in Chickens

To control coccidiosis without using prophylactic medications, a DNA vaccine targeting the gametophyte antigen Gam56 from Eimeria maxima in chickens was constructed, and the immunogenicity and protective effects were evaluated. The ORF of Gam56 gene was cloned into an eukaryotic expression vector pcDNA3.1(zeo)+. Expression of Gam56 protein in COS-7 cells transfected with recombinant plasmid pcDNA-Gam56 was confirmed by indirect immunofluorescence assay. The DNA vaccine was injected intramuscularly to yellow feathered broilers of 1-week old at 3 dosages (25, 50, and 100 µg/chick). Injection was repeated once 1 week later. One week after the second injection, birds were challenged orally with 5×104 sporulated oocysts of E. maxima, then weighed and killed at day 8 post challenge. Blood samples were collected and examined for specific peripheral blood lymphocyte proliferation activity and serum antibody levels. Compared with control groups, the administration of pcDNA-Gam56 vaccine markedly increased the lymphocyte proliferation activity (P<0.05) at day 7 and 14 after the first immunization. The level of lymphocyte proliferation started to decrease on day 21 after the first immunization. A similar trend was seen in specific antibody levels. Among the 3 pcDNA-Gam56 immunized groups, the median dosage group displayed the highest lymphocyte proliferation and antibody levels (P<0.05). The median dosage group had the greatest relative body weight gain (89.7%), and the greatest oocyst shedding reduction (53.7%). These results indicate that median dosage of DNA vaccine had good immunogenicity and immune protection effects, and may be used in field applications for coccidiosis control.

Determining Vaccination Frequency in Farmed Rainbow Trout Using Vibrio anguillarum O1 Specific Serum Antibody Measurements

BackgroundDespite vaccination with a commercial vaccine with a documented protective effect against Vibrio anguillarum O1 disease outbreaks caused by this bacterium have been registered among rainbow trout at Danish fish farms. The present study examined specific serum antibody levels as a valid marker for assessing vaccination status in a fish population. For this purpose a highly sensitive enzyme-linked immunosorbent assay (ELISA) was developed and used to evaluate sera from farmed rainbow trout vaccinated against V. anguillarum O1.Study DesignImmune sera from rainbow trout immunised with an experimental vaccine based on inactivated V. anguillarum O1 bacterin in Freund’s incomplete adjuvant were used for ELISA optimisation. Subsequently, sera from farmed rainbow trout vaccinated with a commercial vaccine against V. anguillarum were analysed with the ELISA. The measured serum antibody levels were compared with the vaccine status of the fish (vaccinated/unvaccinated) as evaluated through visual examination.ResultsRepeated immunisation with the experimental vaccine lead to increasing levels of specific serum antibodies in the vaccinated rainbow trout. The farmed rainbow trout responded with high antibody levels to a single injection with the commercial vaccine. However, the diversity in responses was more pronounced in the farmed fish. Primary visual examinations for vaccine status in rainbow trout from the commercial farm revealed a large pool of unvaccinated specimens (vaccination failure rate = 20%) among the otherwise vaccinated fish. Through serum analyses using the ELISA in a blinded set-up it was possible to separate samples collected from the farmed rainbow trout into vaccinated and unvaccinated fish.ConclusionsMuch attention has been devoted to development of new and more effective vaccines. Here we present a case from a Danish rainbow trout farm indicating that attention should also be directed to the vaccination procedure in order to secure high vaccination frequencies necessary for optimal protection with a reported effective vaccine.

Tolerant beekeepers display venom-specific functional IgG4 antibodies in the absence of specific IgE

Tolerant beekeepers display venom-specific functional IgG4 antibodies in the absence of specific IgE

Measurement of antibodies to pneumococcal, meningococcal and haemophilus polysaccharides, and tetanus and diphtheria toxoids using a 19-plexed assay

The measurement of antibody responses to vaccination is useful in the assessment of immune status in suspected immune deficiency. Previous reliance on enzyme-linked immunoabsorbent assays (ELISA) has been cumbersome, time-consuming and expensive. The availability of flow cytometry systems has led to the development of multiplexed assays enabling simultaneous measurement of antibodies to several antigens. We optimized a flow cytometric bead-based assay to measure IgG and IgM concentrations in serum to 19 antigens contained in groups of bacterial subunit vaccines: pneumococcal vaccines, meningococcal vaccines, Haemophilus influenzae b (Hib), and tetanus and diphtheria toxoid vaccines. 89-SF was employed as the standard serum. The assay was used to determine specific antibody levels in serum from 193 healthy adult donors. IgG and pneumococcal IgM antibody concentrations were measurable across 3 log10 ranges encompassing the threshold protective IgG antibody levels for each antigen. There was little interference between antibody measurements by the 19-plexed assay compared with monoplexed assays, and a lack of cross-reactive IgG antibody, but evidence for cross-reacting IgM antibody for 3/19 pneumococcal antigens. 90th centile values for 15/19 IgG concentrations and 12/12 IgM concentrations of the 193 adult sera were within these ranges and percentages of sera containing protective IgG antibody levels varied from 4% to 95% depending on antigen. This multiplexed assay can simultaneously measure antibody levels to 19 bacterial vaccine antigens. It is suitable for use in standard clinical practice to assess the in vivo immune response to test vaccinations and measure absolute antibody levels to these antigens.

Type IV fimbrial subunit protein ApfA contributes to protection against porcine pleuropneumonia

Porcine pleuropneumonia caused by Actinobacillus pleuropneumoniae accounts for serious economic losses in the pig farming industry worldwide. We examined here the immunogenicity and protective efficacy of the recombinant type IV fimbrial subunit protein ApfA as a single antigen vaccine against pleuropneumonia, or as a component of a multi-antigen preparation comprising five other recombinant antigens derived from key virulence factors of A. pleuropneumoniae (ApxIA, ApxIIA, ApxIIIA, ApxIVA and TbpB). Immunization of pigs with recombinant ApfA alone induced high levels of specific serum antibodies and provided partial protection against challenge with the heterologous A. pleuropneumoniae serotype 9 strain. This protection was higher than that engendered by vaccination with rApxIVA or rTbpB alone and similar to that observed after immunization with the tri-antigen combination of rApxIA, rApxIIA and rApxIIIA. In addition, rApfA improved the vaccination potential of the penta-antigen mixture of rApxIA, rApxIIA, rApxIIIA, rApxIVA and rTbpB proteins, where the hexa-antigen vaccine containing rApfA conferred a high level of protection on pigs against the disease. Moreover, when rApfA was used for vaccination alone or in combination with other antigens, such immunization reduced the number of pigs colonized with the challenge strain. These results indicate that ApfA could be a valuable component of an efficient subunit vaccine for the prevention of porcine pleuropneumonia.

Post-Treatment Follow-Up Study of Abdominal Cystic Echinococcosis in Tibetan Communities of Northwest Sichuan Province, China

BackgroundHuman cystic echinococcosis (CE), caused by the larval stage of Echinococcus granulosus, with the liver as the most frequently affected organ, is known to be highly endemic in Tibetan communities of northwest Sichuan Province. Antiparasitic treatment with albendazole remains the primary choice for the great majority of patients in this resource-poor remote area, though surgery is the most common approach for CE therapy that has the potential to remove cysts and lead to complete cure. The current prospective study aimed to assess the effectiveness of community based use of cyclic albendazole treatment in Tibetan CE cases, and concurrently monitor the changes of serum specific antibody levels during treatment.Methodology/Principal FindingsUltrasonography was applied for diagnosis and follow-up of CE cases after cyclic albendazole treatment in Tibetan communities of Sichuan Province during 2006 to 2008, and serum specific IgG antibody levels against Echinococcus granulosus recombinant antigen B in ELISA was concurrently monitored in these cases. A total of 196 CE cases were identified by ultrasound, of which 37 (18.9%) showed evidence of spontaneous healing/involution of hepatic cyst(s) with CE4 or CE5 presentations. Of 49 enrolled CE cases for treatment follow-up, 32.7% (16) were considered to be cured based on B-ultrasound after 6 months to 30 months regular albendazole treatment, 49.0% (24) were improved, 14.3% (7) remained unchanged, and 4.1% (2) became aggravated. In general, patients with CE2 type cysts (daughter cysts present) needed a longer treatment course for cure (26.4 months), compared to cases with CE1 (univesicular cysts) (20.4 months) or CE3 type (detached cyst membrane or partial degeneration of daughter cysts) (9 months). In addition, the curative duration was longer in patients with large (>10 cm) cysts (22.3 months), compared to cases with medium (5–10 cm) cysts (17.3 months) or patients with small (<5 cm) cysts (6 months). At diagnosis, seven (53.8%) of 13 cases with CE1 type cysts without any previous intervention showed negative specific IgG antibody response to E. granulosus recombinant antigen B (rAgB). However, following 3 months to 18 months albendazole therapy, six of these 7 initially seronegative CE1 cases sero-converted to be specific IgG antibody positive, and concurrently ultrasound scan showed that cysts changed to CE3a from CE1 type in all the six CE cases. Two major profiles of serum specific IgG antibody dynamics during albendazole treatment were apparent in CE cases: (i) presenting as initial elevation followed by subsequent decline, or (ii) a persistent decline. Despite a decline, however, specific antibody levels remained positive in most improved or cured CE cases.ConclusionsThis was the first attempt to follow up community-screened cystic echinococcosis patients after albendazole therapy using ultrasonography and serology in an endemic Tibetan region. Cyclic albendazole treatment proved to be effective in the great majority of CE cases in this resource-poor area, but periodic abdominal ultrasound examination was necessary to guide appropriate treatment. Oral albendazole for over 18 months was more likely to result in CE cure. Poor drug compliance resulted in less good outcomes. Serology with recombinant antigen B could provide additional limited information about the effectiveness of albendazole in CE cases. Post-treatment positive specific IgG antibody seroconversion, in initially seronegative, CE1 patients was considered a good indication for positive therapeutic efficacy of albendazole.

Alum‐type Adjuvant Effect of Non‐haemolytic Saponins Purified from Ilex and Passiflora spp.

Five saponins purified from the leaves of three Ilex species (saponins 1 and 2 from I. dumosa; saponin 3 from I. argentina; saponin 4 from I. paraguariensis) and from Passiflora alata (saponin 5) were evaluated for their in vitro haemolytic activity and in vivo immunostimulatory ability in a mouse model using tetanus toxoid (TT) as a model antigen. The assayed saponins showed very weak or no haemolytic activity over the tested concentration range. Mice were immunized twice with TT formulated with pure saponins 1-5, or with a mixture of saponins from Quillaja saponaria, aluminum hydroxide gel or saline, which were used as controls. The elicited humoral response was evaluated by means of the time course of specific serum antibody levels up to day 131 post-priming (total IgG and isotypes); the cellular response was tested through a delayed-type hypersensitivity (DTH) assay. The assayed saponins, in particular saponins 3 and 5, showed an adjuvant effect similar to that of alum for all tested parameters. The immunostimulating potential of these compounds deserves further investigation, especially taking into account that some Ilex spp. and Passiflora alata are native crops of widespread use and economical importance in Latin America.

Immunological adjuvant effect of Boswellia serrata (BOS 2000) on specific antibody and cellular response to ovalbumin in mice

In this study, the biopolymeric fraction BOS 2000 from Boswellia serrata was evaluated for its potential ability as adjuvants on the immune responses to ovalbumin (OVA) in mice. Balb/c mice were immunized subcutaneously with OVA 100 μg alone or with OVA 100 μg dissolved in saline containing alum (200 μg) or BOS 2000 (10, 20, 40 and 80 μg) on Days 1 and 15. Two weeks later, OVA specific antibodies in serum; concanavalin A (Con A), OVA stimulated splenocyte proliferation, CD4/CD8/CD80/CD86 analysis in spleen cells and its estimation of cytokines (IL-2 and IFN gamma) from cell culture supernatant were measured. OVA specific IgG, IgG1 and IgG2a antibody levels in serum were significantly enhanced by BOS 2000 (80 μg) compared with OVA control group. Moreover, the adjuvant effect of BOS 2000 (80 μg) on the OVA-specific IgG, IgG1, and IgG2a antibody responses to OVA in mice were more significant than those of alum. BOS 2000 significantly enhanced the Con A and OVA induced splenocyte proliferation in the OVA immunized mice especially at a dose of 80 μg (p < 0.001). However, no significant differences were observed among the OVA group and OVA/alum group. At a dose of 80 μg (p < 0.001), there was a significant increase in the CD4/CD8 and CD80/CD86 analysis in spleen cells and cytokine (IL-2 and IFN-gamma) profile in the spleen cell culture supernatant was observed. In conclusion, BOS 2000 seems to be a promising balanced Th1 and Th2 directing immunological adjuvants which can enhance the immunogenicity of vaccine.

Specific serum antibody responses in channel catfish ( Ictalurus punctatus) provide limited protection against Streptococcus ictaluri challenge

Passive immunization studies were conducted to determine the role of specific antibodies in immunity to Streptococcus ictaluri. Adult channel catfish ( Ictalurus punctatus) were injected i.p. with tryptic soy broth as control or with 1.5 × 10 7 colony-forming units (cfu) S. ictaluri/fish at 0, 30, and 60 d, and serum was collected 90 d after the original challenge. Fish were passively immunized by i.p. injection with serum from the tryptic soy broth (TSB) control group, anti- S. ictaluri serum from fish immunized three times and sampled at 90 d (SSI), or heat-inactivated anti- S. ictaluri serum from fish immunized three times and sampled at 90 d (HISSI). These passively immunized fish were then challenged 72 h later with 1.5 × 10 8 cfu S. ictaluri/fish. Over 21 d, the mean cumulative percent survival was 43.3 (TSB), 63.3 (SSI), and 50.0 (HISSI). A significant difference in cumulative percent survival was noted between the TSB and the HISSI groups, and significant differences were noted between these groups and the SSI group. Serum obtained from immunized fish 72 h after passive immunization exhibited increased anti- S. ictaluri antibody levels. Twenty-one days after the challenge, the HISSI and SSI group antibody levels significantly increased above their corresponding pre-challenge levels. No significant ( r 2 = 0.0806; P < 0.5985) correlation between increased pre-challenge specific serum antibody levels and survival after challenge was demonstrated when analyzing the control and passive immunization groups. The results indicate that both specific anti- S. ictaluri antibodies and non-specific immune responses are important for protection against S. ictaluri.