High Initial Titers Research Articles

The immunogenicity of seasonal and pandemic influenza vaccination in autoimmune inflammatory rheumatic patients-a 6-month follow-up prospective study.

Influenza may cause severe complications in patients with autoimmune inflammatory rheumatic disease (AIRD), to whom vaccinations are especially recommended. However, AIRD patients require cautious scrutiny of immunogenicity as theymight exhibit poor antibody response to vaccination, especially when taking immunomodulatory medications. The aim was to determine immunogenicity of seasonal and pandemic influenza vaccine in AIRD patients, its timeline/persistence, and influence of medications on immune response. One hundred and thirty-seven AIRD and 54 healthy controls were vaccinated with trivalent seasonal influenza. After 3-5weeks, 15 healthy controls and 93 AIRD were vaccinated with pandemic influenza vaccine, and 63 of patients were vaccinated a second time after 3-5weeks. Sera were collected before vaccination, 18-90days after each vaccination, and more than 180days after the last vaccination. The immune response was measured using hemagglutination inhibition (HI) assay and IgG/IgA antibodies against influenza A/B with ELISA. Our findings indicate that following vaccination with seasonal influenza vaccine, seroprotection, seroresponse, and change in geometric mean titers (GMT) in AIRD patients was not compromised compared to healthy. Similarly, we report for pandemic influenza vaccination little added benefit of the second dose. We confirm lowest increase in HI titer in rituximab-treated AIRD compared to other medications. Vaccination largely tilts the balance from negative ELISA A IgG and IgA titers to positive titers in seasonal H1N1 seroresponsive AIRD patients and controls. A significant decrease in HIGMT and seroprotection was observed only in AIRD at > 180days after vaccination highlighting an absent persistence of immunogenic response in AIRD patients. Due to high initial HI titers for influenza vaccine, we foresee their benefit in personalized medicine in the future. Influenza vaccination is immunologically active for AIRD, with little value of the second dose of the pandemic vaccine and further scrutiny on persistence of immune response to vaccine in AIRDis needed.

TEROIDES THE STUDY OF THE EFFECT OF HIGH AND LOW STARTING TITRE IN THE MODEL ENVIRONMENTS TO CHANGES IN ACTIVE AND TITRATABLE ACIDITY DURING THE CULTIVATION OF WHITE CABBAGE VARIETIES PARUS LACTIC ACID BACTERIA L. LACTIS AND L. MESENTEROIDES

The aim of the research was to study the dynamics of active and titratable acidity with a low and high initial titer, while cultivating white head cabbage of the variety ‘Parus’ with lactic acid bacteria Leuconostoc lactis VKPM V-12150 and Leuconostoc mesenteroides subsp. mesenteroides VKPM V-8818 in the basic model medium (BMS) and the modified model medium (MMC) during fermentation . In this experiment, two important questions were considered: the creation of favorable conditions for the growth of lactic acid microorganisms and the suppression of undesirable pathogenic microflora, which can eventually lead to product spoilage. One of the key questions is to scale the results of studies related to the fermentation of plant objects by microorganisms on initially non-sterile raw materials that is the requirement to create as possible fast the conditions that restrain the reproduction of Cl. botulinum, preventing toxin accumulation in the product. Therefore, an important factor is the observance for the necessary boundary condition where for international standards, it reaches pH ≤ 4.6, and for Russian standards it reaches pH ≤ 4.2. Hence, an analysis of the experimental data showed that these boundary conditions were reached after the expiration of essentially different time intervals during the cultivation of microorganisms with different starting titers. As a result, it was shown with which lactic acid microorganisms the optimal parameters for the dynamics of active and titratable acidity were obtained, when the boundary condition reached pH 4.2. Since this value determines more stringent requirements for product safety. As a result of studies it was found that optimal parameters for the dynamics of active and titratable acidity when a limit pH value of 4.2 is obtained in the cultivation of lactic acid bacteria L. mesenteroides in the MMC, revealing that the value of the starting titer ranging from 3*103 to 3*105 CFU/g.

ABO-incompatible living donor kidney transplantation without post-transplant therapeutic plasma exchange.

Blood group incompatibility remains a significant barrier to kidney transplantation. Approximately, one-third of donors are blood group incompatible with their intended recipient. Options for these donor-recipient pairs include blood group incompatible transplantation or kidney paired donation. However, the optimal protocol for blood group incompatible transplantation is unknown. Protocols differ in techniques to remove ABO antibodies, titer targets, and immunosuppression regimens. In addition, the mechanisms of graft accommodation to blood group antigens remain poorly understood. We describe a blood group incompatible protocol using pretransplant therapeutic plasma exchange (TPE), high-dose intravenous immunoglobulin, and rituximab in addition to prednisone, mycophenolate mofetil, and tacrolimus. In this protocol, we do not exclude patients based on a high initial titer and do not implement post-transplant TPE. All 16 patients who underwent this protocol received a living donor transplant with 100% patient and graft survival, and no reported episodes of antibody-mediated rejection to date with a median follow-up of 2.6 years (range 0.75-4.7 years). We conclude that blood group incompatible transplantation can be achieved without post-transplant TPE.

Association of bovine respiratory disease or vaccination with serologic response in dairy heifer calves up to three months of age.

To investigate the association of bovine respiratory disease (BRD) or vaccination with serologic response in calves. 94 Holstein calves. To assess the association between BRD and antibody titers, 38 calves < 3 months old that were treated for BRD were matched with 38 untreated calves. To investigate the effect of vaccination on antibody titers, 24 calves were randomly assigned to be vaccinated against bovine respiratory syncytial virus (BRSV), bovine viral diarrhea virus types 1 and 2, bovine herpesvirus type 1 (BHV1), and parainfluenza virus type 3 at 2 weeks of age (n = 6), 5 weeks of age (6), and both 2 and 5 weeks of age (6) or were assigned to be unvaccinated controls (6). Blood samples were obtained at I, 2, 5, and 12 weeks for determination of serum neutralization antibody titers against the vaccine viruses, bovine coronavirus, and Mannheimia haemolytica. Antibody rates of decay were calculated. Calves with initial antibody titers against BRSV < 1:64 that were treated for BRD had a slower rate of anti-BRSV antibody decay than did similar calves that were not treated for BRD. Calves with high initial antibody titers against BRSV and BHV1 had lower odds of BRD than did calves with low initial antibody titers against those 2 pathogens. Vaccination at 2 or 5 weeks of age had no effect on the rate of antibody decay. Clinical BRD and the serologic response of dairy calves were associated with initial antibody titers against BRSV and BHV1. Serologic or clinical responses to viral exposure may differ in calves with low passive immunity.

Photodynamic inactivation of enveloped virus in protein plasma preparations by solid-phase fullerene-based photosensitizer

The problem of transfusion-transmitted infections still remains serious and actual for health care despite the detailed testing of donors. Human immunodeficiency virus, hepatitis B and C viruses and human cytomegalovirus are among the most dangerous pathogens that can be transmitted with blood. Previously, a composition consisting of fullerene layer applied on silica gel particles was shown to inactivate influenza virus up to complete loss of infectivity. In the present study the unit has been developed with source of irradiation whose spectrum is appropriate for solid-phase fullerene. The ability of the unit to inactivate the enveloped influenza virus in protein fraction of donor blood has been studied. It was shown that at optimized conditions complete inactivation of enveloped virus of extremely high initial titer (7.0-9.5 log 10 EID 50/0.2 mL) in the solution of albumin was achieved after as short time as 30 min of irradiation. This process did not affect the oxidative metabolism of neutrophils and membranes of erythrocytes evaluated by NBT reduction test and morphological analysis of erythrocytes, respectively. The data obtained suggests that the method described can be recommended for further development and optimization of the procedure of inactivation of viruses in the preparations of the plasma of donor blood.

Significance of isoagglutinin titer in ABO-incompatible kidney transplantation

ABO-incompatible (ABO-i) kidney transplantation (KT) has emerged for overcoming the shortage of organ donors. Although this technique initially achieved only low graft survival due to isoagglutinin, recently developed desensitization protocols have improved survival to levels that are comparable to ABO-compatible KT. However, isoagglutinin is still regarded as a major obstacle to ABO-i KT. In this study, we evaluate the impact of isoagglutinin titer on clinical outcomes as well as factors that may influence isoagglutinin titers. In total, data from 95 patients who underwent ABO-i KT were analyzed. Preoperatively, rituximab administration and plasmapheresis were performed until the titer was reduced to ≤1:4. Retrospective analysis included blood group; timing and dosage of rituximab; isoagglutinin titer; number of plasmapheresis; and clinical outcomes including graft survival and serum creatinine. Graft survival was 95.8% (n = 91) and average serum creatinine at 1- and 1.5-year post-ABOi-KT was 1.3. Three patients died of sepsis. The identified predictors of titer-rebound after transplant were short interval (<7 days) between rituximab and first plasmapheresis (P = 0.004); high initial titer (≥256) (P = 0.023); low titer-reduction rate (P < 0.001); and blood group O (P < 0.001). One patient who experienced a rebound developed antibody-mediated rejection. With low-dose (200 mg) rituximab, the change in isoagglutinin titer-rebound was not significant and the infection rate was significantly decreased (P = 0.001). In conclusion, isoagglutinin titer-rebound within the first 2 weeks after KT may be a risk factor for rejection. The factors identified as affecting titer-rebound after KT were high initial isoagglutinin titer, low titer-reduction rate, short interval, and blood group O.

ABO-incompatible living donor liver transplantation is suitable in patients without ABO-matched donor

ABO-incompatible liver transplantation is usually contraindicated because of the risk of antibody-mediated humoral rejection of the graft. We describe 22 successful cases of patients who had living donor liver transplantation (LDLT) from ABO-incompatible donors. The immunosuppressive protocol consisted of rituximab and plasmapheresis prior to LDLT. Plasmapheresis was planned for up to 2 weeks after LDLT aiming at maintaining levels of anti-ABO titers below 1:32. The median age of recipients was 54 years and the median MELD score was 13. The initial range of isoagglutinin IgM and IgG titers were 1:8-1:1024 and 1:2-1:1024, respectively. Preoperative isoagglutinin IgM and IgG titers were achieved less than or equal to 1:8 by performing therapeutic plasma exchange (TPE). While the median number of TPE was 4 (range, 2-18) in all patients, it was 4 (range, 2-8) in the initial low titer group (<1:256) and 8 (range, 6-18) in the high titer group (≥ 1:256). There were no statistically significant differences for liver function tests in the first 2 weeks after transplantation between the groups having high MELD score (≥ 20) vs. low MELD score (<20), local graft infusion vs. systemic infusion, or high initial isoagglutinin titer (≥ 1:256) vs. low initial isoagglutinin titer (<1:256). Patient and graft survival was 100% and there was no acute humoral rejection in recipients at a mean follow-up of 10months (range, 3-21). ABO-incompatible LDLT can be safely performed when rituximab and TPE are used, and may be proposed when ABO-compatible donors are not available.

Modulation of Serum Antinuclear Antibody Levels by Levamisole Treatment in Patients With Oral Lichen Planus

Serum autoantibodies, including antinuclear antibodies (ANAs), have been found in patients with oral lichen planus (OLP). This study evaluated whether Taiwanese OLP patients had significantly higher frequencies of serum ANAs than healthy control subjects, and whether levamisole treatment could modulate the antibody levels. This study used an indirect immunofluorescence technique to measure the baseline serum levels of ANA in a group of 583 Taiwanese OLP patients and 53 healthy control subjects. Seventy-nine ANA-positive OLP patients were treated with levamisole under a regular follow-up schedule in our dental clinic, and their serum ANA levels were measured after treatment. We found that the frequencies of serum ANA in patients with OLP (23.2%), erosive OLP (EOLP, 23.8%), major EOLP (31.5%), and minor EOLP (18.1%) were all significantly higher than that (5.7%) in healthy control subjects. In addition, major EOLP patients had a significantly higher serum ANA positive rate than minor EOLP or non-erosive OLP patients. Of 135 ANA-positive OLP patients, 79 were treated with levamisole under a regular follow-up schedule. We found that treatment with levamisole for a period of 2-38 months (mean, 12 ± 9 months) effectively reduced the high mean serum ANA titer (557 ± 98) at baseline to an undetectable level (0) in all ANA-positive OLP patients, regardless of different high initial serum titers of ANA. There was a significantly higher frequency of serum ANA (23.2%) in Taiwanese OLP patients than in healthy control subjects. Treatment with levamisole for 2-38 months reduced the high serum ANA to an undetectable level, and significantly improved the signs and symptoms in all treated OLP patients.

The T7-Related Pseudomonas putida Phage φ15 Displays Virion-Associated Biofilm Degradation Properties

Formation of a protected biofilm environment is recognized as one of the major causes of the increasing antibiotic resistance development and emphasizes the need to develop alternative antibacterial strategies, like phage therapy. This study investigates the in vitro degradation of single-species Pseudomonas putida biofilms, PpG1 and RD5PR2, by the novel phage ϕ15, a ‘T7-like virus’ with a virion-associated exopolysaccharide (EPS) depolymerase. Phage ϕ15 forms plaques surrounded by growing opaque halo zones, indicative for EPS degradation, on seven out of 53 P. putida strains. The absence of haloes on infection resistant strains suggests that the EPS probably act as a primary bacterial receptor for phage infection. Independent of bacterial strain or biofilm age, a time and dose dependent response of ϕ15-mediated biofilm degradation was observed with generally a maximum biofilm degradation 8 h after addition of the higher phage doses (104 and 106 pfu) and resistance development after 24 h. Biofilm age, an in vivo very variable parameter, reduced markedly phage-mediated degradation of PpG1 biofilms, while degradation of RD5PR2 biofilms and ϕ15 amplification were unaffected. Killing of the planktonic culture occurred in parallel with but was always more pronounced than biofilm degradation, accentuating the need for evaluating phages for therapeutic purposes in biofilm conditions. EPS degrading activity of recombinantly expressed viral tail spike was confirmed by capsule staining. These data suggests that the addition of high initial titers of specifically selected phages with a proper EPS depolymerase are crucial criteria in the development of phage therapy.

In Vitro Effects of Pomegranate Juice and Pomegranate Polyphenols on Foodborne Viral Surrogates

Pomegranate juice (PJ) has gained popularity because of its associated antioxidant, antimicrobial, anticancer, and anti-inflammatory properties. However, its effects against epidemiologically significant foodborne viruses have not been investigated. In the absence of culturable human noroviruses, feline calicivirus (FCV-F9), murine norovirus (MNV-1), and MS2 (ssRNA) bacteriophage were used as foodborne viral surrogates. The aim of this research was to study the effects of PJ and pomegranate polyphenols (PP) on foodborne viral infectivity. Viruses at high (∼ 7 log(10) PFU/mL) or low (∼ 5 log(10) PFU/mL) titers were mixed with equal volumes of PJ, 8, 16, and 32 mg/mL of PP, or water (control) and incubated for 1 h at room temperature. Viral infectivity after treatments was evaluated using standardized plaque assays. PJ decreased the titer of FCV-F9, MNV-1, and MS2 by 2.56, 1.32, and 0.32 log(10) PFU/mL, respectively, for low titers and 1.20, 0.06, and 0.63 log(10) PFU/mL, respectively, for high titers. Interestingly, FCV-F9 was undetectable after exposure to the three tested PP solutions using both low and high titers. MNV-1 at low initial titers was reduced by 1.30, 2.11, and 3.61 log(10) PFU/mL and at high initial titers by 1.56, 1.48, and 1.54 log(10) PFU/mL with 4, 8, and 16 mg/mL of PP treatment, respectively. MS2 at low initial titers was reduced by 0.41, 0.45, and 0.93 log(10) PFU/mL and at high initial titers by 0.32, 0.41, and 0.72 log(10) PFU/mL after 4, 8, and 16 mg/mL of PP treatment, respectively. PJ and PP resulted in titer reductions of foodborne virus surrogates after 1 h exposure, showing promise for use in hurdle technologies and/or for therapeutic or preventive use. To suggest the use of PJ and PP as natural remedies for foodborne viral illness prevention, their mechanism of action against viral infectivity needs to be further investigated.

Probable Deceleration of Progression of Simian AIDS Affected by Opiate Dependency: Studies With a Rhesus Macaque/SIVsmm9 Model

To determine effects of opiate dependency on development of simian AIDS. Assessments of viral, immune, and clinicopathological status were conducted on rhesus macaques before and after establishment of opiate dependency and Simian Immunodeficiency Virus, sooty mangabey, strain-9 (SIVsmm9) infection. Controls received saline. Blood was collected at baseline, before opiate dependencies, and viral infections were established and then after SIVsmm9 infection, longitudinally, through 216 weeks. Plasma viral titers were assessed using the branched chain DNA assay and CD4 and CD8 counts via cytofluorometry. Clinicopathological assessments of AIDS were founded on Centers for Disease Control and Prevention and other selected criteria. AIDS progression rates seemed to be decelerated and survival times increased by opiate dependency. Mean viral titers were unaffected by opiate exposure. Opiate-dependent monkeys that evidenced high initial viral titers survived significantly longer than controls. Several opiate-dependent monkeys maintained high viral titers for atypically extended durations. Several (5/19) opiate-dependent monkeys died or were removed early from the study due to "non-AIDS" causes. Long-term opiate dependency seemed to decelerate the rate of progression to AIDS in the SIVsmm9 monkey model. This effect was most evident in monkeys with high initial viral titers/set points. "Non-AIDS" morbidities and mortalities were noted as potential confounds of epidemiological assessments of the role of opiates in HIV/AIDS.

Preemptive Postoperative Antigen-Specific Immunoadsorption in ABO-Incompatible Kidney Transplantation: Necessary or Not?

Several standard protocols for ABO-incompatible kidney transplantation use scheduled preemptive antigen-specific immunoadsorption during the postoperative period. Our center has developed a different approach. Our patients undergo antigen-specific immunoadsorption postoperatively only if their isoagglutinine titers (immunoglobulin G anti-A/B) exceed 1:8 in the first postoperative week and 1:16 in the second postoperative week. Using this strategy, 22 ABO-incompatible kidney transplantations have been performed at our center since 2004. Only 32% of these patients (7 of 22) needed to undergo postoperative immunoadsorption (mean 4.1 immunoadsorption sessions per patient). The renal outcome in patients receiving postoperative immunoadsorption treatment versus the outcome in patients without postoperative immunoadsorption remained equal at a mean follow-up of 17 months. We identified a shorter pretransplant time on dialysis, a blood type constellation of donor A1/recipient O, and high initial starting titers as predictors for the need for postoperative immunoadsorption treatment. A more detailed version of this study, with modified tables and figures, has been accepted for publication in Nephrology Dialysis Transplantation.

ABO‐incompatible kidney transplantation—Proposal of an intensified apheresis strategy for patients with high initial isoagglutinine titers

Since Tydén's description of ABO-incompatible (ABOi) kidney transplantations based on antigen-specific immunoadsorption (IA) and rituximab (Tydén et al., Am J Transplant 2005;5:145-148), this technique has been successfully adopted by many transplant centers worldwide. The majority of centers strictly adhere to the Swedish protocol and perform IAs with a target volume of 1.5-2 plasma volumes on preoperative days -6, -5, -2, and -1, and postoperative days +3, +6, and +9, respectively. Patients who initially present with an IgG anti-A/B titer higher than 1:128 are not considered suitable candidates for ABOi transplantation by the Swedish protocol. Our center has gone beyond these suggestions and follows a slightly different strategy: We do not exclude patients with initial IgG anti-A/B titers higher than 1:128 and we perform as many preoperative antigen-specific extracorporeal treatments as needed to reach a threshold isoagglutinine titer of 1:4 or less. To intensify isoagglutinine clearance preoperatively, the total target volume per treatment was increased to 2.5-3 plasma volumes. Preconditioning IAs are performed every other day, instead of daily. Postoperatively we perform IAs only, if titers mandate us to do so (Wilpert et al., Nephrol Dial Transplant 2007;22:3048-3051). We report on 11 "high-titer patients" who entered our ABOi kidney transplant program with initial titers of 1:256 or above. Seven of 11 patients (64%) could successfully be transplanted with our modified ABO-apheresis protocol. Four of 11 high-titer patients did not reach target isoagglutinine titers of 1:4 or less and therefore did not undergo transplantation. We conclude that intensified preoperative IA renders a majority of high-titer patients suitable candidates for ABOi kidney transplantation.

Effectiveness of Syphilis Treatment Using Azithromycin and/or Benzathine Penicillin in Rakai, Uganda

The goal of this study was to assess azithromycin and/or benzathine penicillin for treatment of syphilis. In a population-based study, participants with serologic syphilis (TRUST with TPHA confirmation) were offered 2.4 MU benzathine penicillin intramuscularly. Intervention arm participants received 1 g presumptive oral azithromycin. We assessed cure rates with penicillin or azithromycin given alone and in combination. Cure assessed after 10 months was defined as seroreversion or a 4-fold decrease in titer. The rate ratio (RR) of cure and 95% confidence intervals (95% CIs) were estimated by log binomial regression. Among 952 cases with syphilis, 18% received penicillin alone, 17% azithromycin only, and 65% dual treatment. The overall cure rate was 61%. Cure rates were lower in males compared with females (RR, 0.89; 95% CI, 0.80-0.99) and in subjects with initial titers > or =1:4 compared with < or =1:2 (RR, 0.77; 95% CI, 0.69-0.86). There was no significant differences in cure rates among HIV-positive and HIV-negative persons. With initial titers < or =1:2, there were no differences in cure rates by treatment regimen. However, with initial titers > or =1:4, significantly higher cure rates were observed with azithromycin alone (adjusted RR, 1.38; 95% CI, 0.97-1.96), and with dual treatment of azithromycin and benzathine penicillin (RR, 1.38; 95% CI, 1.03-1.87) compared with penicillin alone. Azithromycin alone or in combination with penicillin achieved higher cure rates than penicillin alone in cases with a high initial TRUST titer. In low-titer infections, the 3 drug combinations were equally effective. HIV status did not affect cure rates.

Retrospective Analysis of the Serologic Response to the Treatment of Syphilis During Pregnancy

Objective: The purpose of this study was to assess the effect of several maternal variables on the serologic response following the treatment of syphilis in pregnancy. Methods: A 5-year chart review identified 95 patients coded with syphilis at Hermann Hospital. Inclusion criteria were 1) serologically confirmed syphilis infection during the index pregnancy, 2) complete treatment during the index pregnancy, and 3) minimum of one follow-up rapid plasma reagin (RPR) titer. Forty-nine of 95 patients met the inclusion criteria. Treatment response was evaluated by comparing each post-treatment titer of a patient to her pretreatment titer. Each comparison was considered an “observation.” Each observation was classified as either a positive response (≥4-fold titer decline) or a negative response (<4-fold titer decline). Maternal variables assessed included 1) prior history of syphilis untreated or incompletely treated prior to the index pregnancy, 2) gestational age, 3) titer level, 4) unknown duration, 5) positive response at 1 month, 6) positive response at 2 months, 7) positive response at >3 months, and 8) race. Results: A positive response following treatment was significantly more likely if there was no prior history of syphilis or if there was a high initial RPR titer (>32). Only 33/54 (61%) observations at or greater than 3 months had a positive response. Conclusions: Our study suggests that an absence of a history of syphilis and an initial high RPR titer are predictive of a positive response following appropriate treatment. Given the low percentage of observations with a positive response at 3 months, we speculate that we may be undertreating our pregnant patients with syphilis infection.

Retrospective analysis of the serologic response to the treatment of syphilis during pregnancy

Objective The purpose of this study was to assess the effect of several maternal variables on the serologic response following the treatment of syphilis in pregnancy. Methods A 5-year chart review identified 95 patients coded with syphilis at Hermann Hospital. Inclusion criteria were 1) serologically confirmed syphilis infection during the index pregnancy, 2) complete treatment during the index pregnancy, and 3) minimum of one follow-up rapid plasma reagin (RPR) titer. Forty-nine of 95 patients met the inclusion criteria. Treatment response was evaluated by comparing each post-treatment titer of a patient to her pretreatment titer. Each comparison was considered an “observation.” Each observation was classified as either a positive response (≥4-fold titer decline) or a negative response (<4-fold titer decline). Maternal variables assessed included 1) prior history of syphilis untreated or incompletely treated prior to the index pregnancy, 2) gestational age, 3) titer level, 4) unknown duration, 5) positive response at 1 month, 6) positive response at 2 months, 7) positive response at >3 months, and 8) race. Results A positive response following treatment was significantly more likely if there was no prior history of syphilis or if there was a high initial RPR titer (>32). Only 33/54 (61%) observations at or greater than 3 months had a positive response. Conclusions Our study suggests that an absence of a history of syphilis and an initial high RPR titer are predictive of a positive response following appropriate treatment. Given the low percentage of observations with a positive response at 3 months, we speculate that we may be undertreating our pregnant patients with syphilis infection. Infect. Dis. Obstet. Gynecol. 5:23–28, 1997. © 1997 Wiley-Liss, Inc

Genetic variation in antibody response to diphtheria toxoid in Atlantic salmon and rainbow trout

Antibody response to diphtheria toxoid in rainbow trout (202 fish belonging to 28 full-sib pairs within 14 half-sib groups) and Atlantic salmon (791 fish belonging to 34 full-sib pairs within 12 half-sib groups) was determined by analyzing blood samples taken on three different occasions. The fish were immunized twice with the antigen during the experiment. Antibody levels were measured by an enzyme-linked immunoadsorbent assay (ELISA). A method of estimating titers from three serum dilutions was worked out to avoid end-point titration of the large number of samples. The rainbow trout responded well to immunization, and genetic variation in antibody titers was observed both before and after the first immunization (h2 = 0.2). The Atlantic salmon had high initial titers to diphtheria toxoid and the response to immunization was weak. This suggests an impact of natural or cross-reacting antibodies. The heritabilities for antibody levels were lower in this species (0.12 and less). There were high genetic and phenotypic correlations between the antibody measurements at the three samplings. Antibody response to diphtheria toxoid correlated negatively with survival after challenge with V. anguillarum. No correlation was observed between antibody level and production traits (mean slaughter weight and survival rate) for full-sib groups reared at different sea locations.

Effect of Jackbean Urease Injections and Chlortetracycline on Rate of Gain and Feed Efficiency in Swine

Two trials involving fifty-five Yorkshire × Poland China barrows were conducted to study the effects of immunity to jackbean urease on rate of gain and feed efficiency in swine. In the first trial, with factorially-arranged treatments including 100 ppm chlortetracycline in the diet and 100 Sumner units of urease injected intraperitoneally, chlortetracycline improved (P<.01) rate of gain and feed efficiency while the urease did not. A high initial serum titer against urease was observed, and further injections failed to increase this titer. In the second trial injections of up to 300 Sumner units of urease failed to increase the initial titer against urease and had no effect on feed efficiency and rate of gain. A technique of assaying for antiurease titer that involves a direct urease assay is reported.

ANTIBODY RESPONSE TO THYROID IRRADIATION.

Serial measurements of thyroid auto-antibody titers by complement fixation and tanned red cell agglutination methods have been made in 30 patients with thyrotoxicosis, before and following treatment with radioactive iodine. A rise in titer by one or both methods was demonstrated in 18 subjects. In 13 it was transient, the maximum response being observed between 4 and 40 weeks, whereas in 5 the rise in titer was delayed and persisted throughout the period of observation. Five subjects developed myxedema; 2 of these had a high initial titer of antithyroglobulin while the other 3 all had a rise in antibody titer after treatment. The findings are discussed, and it is suggested that physical trauma to the thyroid caused by irradiation may lead to the development of an auto-immune process in some patients.

Relationship of immune response to group A streptococci to the course of acute, chronic and recurrent rheumatic fever

The clinical course of rheumatic fever in relation to the factor of streptococcal infection was studied in 580 patients. A high initial titer of either antistreptolysin O, antistreptokinase or antihyaluronidase was found in the sera of 95 per cent of patients who could be studied within the first two months of onset of the rheumatic attack. This figure approached 100 per cent in those studies made closer to the onset of the attack. The rate of fall of these three antibodies bore no relationship to the subsequent clinical course of the rheumatic attack. Following suppressive therapy with aspirin or cortisone, all frank relapses of the disease which were unassociated with new streptococcal infection occurred within two months. Thereafter, the reappearance of frank rheumatic fever was invariably associated with immunologic evidence of new streptococcal infection. The implications of these findings for the management of the rheumatic subject and the effect of antistreptococcal prophylaxis upon the natural history of the disease are discussed.