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At least 649 records · Page 36Linked to original sources
PubMed1989

Immunoregulation of anti-islet cell antibody in insulin-dependent diabetes: failure to detect anti-idiotypic antibody following seroconversion.

A search was made for the presence of spontaneous auto-anti-idiotype in sera of three insulin-dependent diabetics when they converted from islet cell antibody positive to islet cell antibody negative states. Rabbit anti-idiotype specific for islet cell antibody was used as the positive control. Using an enzyme-linked immunoabsorbent assay, binding of the rabbit anti-idiotype to idiotype-coated plates could not be inhibited by islet cell antibody negative sera. Using this same assay, there was no significant difference in the binding of islet cell antibody positive or negative sera to either idiotype-coated or normal IgG-coated plates. Binding of islet cell antibody to pancreatic sections could not be inhibited by islet cell antibody negative sera in an immunofluorescent assay. Network regulation by auto-anti-idiotype does not seem to play a role in the decline or absence of islet cell antibody in the early phases of insulin-dependent diabetes mellitus.

Antibodies, Anti-Idiotypic↗
PubMed1990

Seroconversion of recipient ewes after transfer of ova exposed to Brucella ovis in vitro.

Zona pellucida-intact ova collected from ewes seronegative to Brucella ovis were exposed in vitro to B ovis and washed 10 times in medium that contained no antibiotics. After exposure and washing, nontransferable ova were cultured for isolation of Brucella , and the viable ova were transferred into seven B ovis seronegative ewes. No pregnancies resulted, thus recipient ewes were bred during the next breeding season, and blood samples were collected for bacteriological and serological examination until one month after lambing. Brucella ovis was isolated from all of the nontransferable ova, indicating that the transferred ova had viable organisms adhered to them. Although no recipient was found to be pregnant at Day 45, all seven ewes responded to the transferred ova by producing anti-Brucella antibodies. With the exception of a ewe that was euthanized early in the project due to a traumatic injury, all recipients lambed normally during the following breeding season. Brucella was not found in any sample collected from ewes or lambs. However, ELISA titers for B ovis remained in the suspicious range and a ewe was positive on the CF test within 2 wk of lambing.

Journal Article↗
PubMed1993

Seroconversion for Helicobacter pylori.

The prevalence of Helicobacter pylori antibodies increases with age, but it is unknown whether this is due to a constant rate of infection in different age groups, or whether most infection occurs in childhood. Follow-up data on infection rates and the course of infection in an untreated population are scarce. We measured H pylori IgG antibody concentrations in patients who were seen at our endoscopy unit between 1979 and 1983. 115 of 164 eligible patients (70%) participated in the study. H pylori IgG antibody concentrations were measured in two serum samples taken with a mean interval of 11.5 years. 56 patients tested positive at the first visit. During follow-up, 2 patients became infected (annual infection rate 0.30%, 95% Cl 0.04-1.08%). Evidence of infection disappeared in 6 patients: after gastric surgery in 3 and due to an unknown cause in the remaining 3 patients. A non-significant decrease of infection was shown in different age cohorts during follow-up. Antibody concentrations did not increase with age. These results strongly support the concept of dominant infection rates in childhood. Elimination of infection may occur in a few patients without eradication therapy.

Adolescent↗
PubMedDate not supplied

Acute meningoradiculitis concomitant with seroconversion to human immunodeficiency virus type 1.

We report a case of acute regressive meningoradiculitis concomitant with HIV1 primoinfection. The clinical symptoms were mild and disappeared spontaneously. Electromyographic studies confirmed the regressive demyelinating-type process. The biological diagnosis of HIV1 infection was demonstrated by viral antigen detection, by the presence of the integrated proviral DNA after gene amplification by a polymerase chain reaction, and in particular, by the steady progression in the appearance of different HIV1-specific antibodies. This was shown using three different Western blot kits whose performances were compared.

Acute Disease↗
PubMed2005

Mycoplasma penetrans infections and seroconversion in patients with AIDS: identification of major mycoplasmal antigens targeted by host antibody response.

We examined Mycoplasma penetrans-specific antibodies in sera of five male homosexual AIDS patients from whom M. penetrans was isolated during the disease process. No consistent immune reaction pattern could be recognized in Western blot using whole cell proteins. Serum samples obtained prior to M. penetrans isolation reacted with a number of M. penetrans proteins, most likely due to non-specific cross-reactions. Further analysis revealed that patients produced prominent antibody reaction to lipid-associated membrane proteins (LAMPs) of M. penetrans at the time of mycoplasma isolation, which could not be observed for serum samples obtained prior to M. penetrans isolation. The positive antibody reaction was mainly directed against two major LAMPs of M. penetrans with molecular mass of 35 and 38 kDa and produced a distinctive pattern of positive immunoreaction bands. Our observation suggested that, comparing with whole mycoplasmal proteins, LAMPs were more specific target antigens in serological assays for M. penetrans infection.

AIDS-Related Opportunistic Infections↗
PubMed2005

Pneumococcal seroconversion after vaccination for children with atopic dermatitis treated with tacrolimus ointment.

OBJECTIVE: We sought to determine the effect of treatment with topical tacrolimus on B- and T-cell immunity including the primary antibody response to pneumococcal polysaccharide vaccine in children with atopic dermatitis. METHODS: In this open-label, noncomparative study, 23 children aged 2 to 12 years with moderate to severe atopic dermatitis were treated with tacrolimus 0.03% ointment twice daily for 7 weeks, immunized with a 23-valent pneumococcal polysaccharide vaccine after 3 weeks of treatment, and had their antibody response measured (for 12 pneumococcal serotype antigens present in the vaccine) before and 4 weeks after vaccination. None had received pneumococcal vaccine before the study. Patient antibody and cellular immune responses were assessed at each study visit (baseline, week 3, and week 7). RESULTS: No significant changes in complete blood cell count, lymphocyte subsets, CD4/CD8 ratio, immunoglobulin levels, antibody titers to tetanus and Haemophilus influenzae , or lymphoproliferative responses were noted during the tacrolimus ointment treatment period. Tacrolimus blood levels were 1 ng/mL or less in all 23 children. Protective pneumococcal titers to all 12 serotypes were observed in 2 of 23 (9%) children prevaccination and in 16 of 23 (70%) children postvaccination. All 6 children who had protective titers to 0 to 5 of the 12 serotypes developed protective titers to an additional 5 to 11 serotypes. Of the patients, 91% had a greater than 4-fold increase in titer for at least 4 of 12 pneumococcal serotypes. CONCLUSION: Topical application of tacrolimus ointment does not affect the serologic response to pneumococcal vaccine or interfere with preexisting T- and B-cell immune responses.

Antibodies, Bacterial↗
PubMed2005

HIV-seroconversion following sexual abuse.

Transkei is a poverty stricken former black homeland, now a part of the Eastern Cape Province. Unemployment and the incidental violence are very high. Women are mainly responsible for bringing up their children. Single parenting is also common in this community. Sexual abuse of children is selected to be under-reported. This reports the case of a 13-year-old girl who was raped twice within three months and brought to the Sinawe Centre of the Nelson Mandela Academic Hospital. Failure to adhere to post exposure prophylaxis (PEP) has undermined the implementation of antiretroviral roll out programme by the government. The history, physical examination and laboratory investigations of this case are given. Preventive steps are suggested.

Adolescent↗
PubMed2006

Detection of cytomegalovirus infection during a vaccine clinical trial in healthy young women: seroconversion and viral shedding.

BACKGROUND: An antibody method based on absorption of serum with cytomegalovirus (CMV) glycoprotein B (gB) was developed for detection of infection during clinical trials of CMV gB vaccine. Previous study showed that this method detected the antibody response to infection and was negative with vaccine induced immunity. OBJECTIVES: In an ongoing efficacy trial of CMV gB vaccine the ability of the gB-absorbed CMV IgG assay to detect CMV infection was assessed and compared with viral culture results. STUDY DESIGN: Two hundred and ninety two healthy, seronegative young women in a phase II, double-blind, placebo-controlled, clinical trial of recombinant CMV gB vaccine (sanofi pasteur) with MF59 adjuvant (Chiron) were randomized to receive CMV gB vaccine or placebo (1:1) on a 0, 1 and 6 month schedule. Participants were screened every 3 months for CMV infection using the gB-absorbed CMV IgG assay, and a subgroup was also screened for infection with viral cultures. Viral culture (urine, vaginal swab and saliva) was used to confirm CMV infection in all subjects with a positive gB-absorbed CMV IgG result. RESULTS: Evidence of CMV infection (gB-absorbed CMV IgG levels>or=5.0 AU/ml) was found in 23/292 (7.88%) study participants. The gB-absorbed CMV IgG levels of their first positive serum ranged from 15.7 to 251.0 AU/ml with a mean of 77.0 AU/ml and a median of 44.9 AU/ml. Cytomegalovirus was isolated from all 23 of them from culture specimens collected after their first positive gB-absorbed CMV IgG. The time to first CMV positive culture from first positive gB-absorbed CMV IgG ranged from 0 to 12 weeks with a median of 2 weeks. CONCLUSIONS: The gB-absorbed CMV IgG assay detects CMV infection in CMV gB vaccine clinical trials earlier and more rapidly than virus culture and does not reveal whether subjects received CMV gB vaccine or placebo.

Antibodies, Viral↗