Rapidly decreased serum IgG to Campylobacter pylori following elimination of Campylobacter in histological chronic biopsy Campylobacter-positive gastritis

The anaerobic bacterium Campylobacter pylori (Cp) is thought to be associated with chronic gastritis. This paper presents clinical data underpinning this view. Five patients with histological chronic gastritis as determined by diagnostic endoscopy, which was associated with Cp as determined by positive biopsy cultures, all possessed statistically raised serum IgG ELISA titers to Cp during a longitudinal period of observation of 15 months. Treatment with the antibiotics amoxycillin (clamoxyl) or colloidal bismuth subcitrate (denol) eliminated Cp within one month. Associated with this, serum IgG ELISA titers were found to decrease sharply and rapidly. Tagamet and spiramycin had little effect. Although the data are preliminary, they support the assumed Cp involvement in chronic gastritis and suggest that specific serum IgG ELISA titers to Cp are useful parameters in monitoring disease status, exceeding bacteriological culture of biopsy specimens in speed and convenience.

The serotype distribution of Campylobacter in patients with diarrhoea in Kuwait

Fifty one strains of Campylobacter jejuni/coli isolated from patients with diarrhoea, at the Amiri Hospital, Hawally, Kuwait were classified on the basis of the heatstable-HS-antigens and the heat-labile-HL-antigens, by using 20 and 23 hyperimmune antisera for the two methods, respectively. The ages of the patient ranged from 3 months to 60 years, and 72.6% of the strains were from children less than 4 years. With the number of antisera used 78.4% of the HS antigens and 96.1% of the HL antigens could be identified. About half of the strains had one of five HS antigens (4, 8, 13, 5 or 25) and 70.5% of the strains had one of five HL antigens (1, 36, 2, 6, or 21). The study shows that the most common HS and HL antigens among Campylobacter strains from Kuwait also are the most frequent antigens of strains from other parts of the world. A limited number of antisera are sufficient to identify the majority of the strains.

Detection of antibody responses in rabbits hyperimmunized with Campylobacter pylori. Enzyme immunoassay indicates extensive antigenic similarities

Acid glycine extracts from four Campylobacter pylori strains and one GCLO strain were used as antigens in enzyme immunoassay (EIA). Immune responses of rabbits immunized with C. pylori strains, the GCLO-strain and other campylobacter strains were studied. All 14 rabbit antisera against C. pylori reacted with all four C. pylori extracts and there were extensive cross-reactions between these extracts. Antisera against C. jejuni and C. coli strains did not react with a C. pylori extract but reached with the GCLO antigen. Acid glycine extracts proved to be very satisfactory in C. pylori serology and the use of an extract prepared from only one strain instead of a combination of strains seems justified.

The source of Campylobacter pylori

Sera from 98 abattoir workers were tested for IgG as well as for IgA to Campylobacter pylori, C. jejuni and Klebsiella. Clerical workers had significantly lower C. pylori and C. jejuni antibody levels than any of the groups in direct contact with freshly cut animal parts. No difference was found for antibodies to Klebsiella. Twenty-nine non-clerical workers with high IgG antibody levels against C. pylori consented to upper gastrointestinal endoscopy. C. pylori associated gastritis was found in all 29, and 4 weeks of colloidal bismuth subcitrate (240 mg/twice daily) was prescribed. On repeat testing at 3 months, all showed a decrease in IgG antibody levels to C. pylori but not to C. jejuni, whereas 18 untreated non-endoscoped workers showed no change. These findings raise the possibility that C. pylori infection is a zoonosis.

The role of serology in the diagnosis of Campylobacter pylori infection

Circulating antibodies to Campylobacter pylori in patients with campylobacter-associated gastritis are sufficiently specific to allow serodiagnosis of this condition. This is possible by various techniques, the most convenient being enzyme-linked immunosorbent assay. Applications of serodiagnosis are in two areas--in clinical practice, where proper evaluation is still required, and in epidemiology. Here serodiagnosis shows the prevalence of C. pylori in the general population and in specific population groups. A study of C. pylori and dyspeptic symptoms in a group of healthy blood donors showed a significant association between C. pylori and history of peptic ulceration. However in most donors the gastritis was clinically silent.

Age-dependent increase of Campylobacter pylori antibodies in blood donors

Antibodies against Campylobacter pylori were determined in 500 blood donors aged 18 to 65 years. Acid extract from a C. pylori strain was used as antigen in enzyme immunoassay. The proportion of donors with high antibody titers increased with age. For IgG antibodies it was 10% in the age group from 18 to 25 years but 60% in the group from 56 to 65 years; the increase for IgA and IgM antibodies was from 5 to 42% and from 7 to 21%, respectively. The geometric mean titers of those with high values showed no clear changes with age, which would imply chronic antigenic stimulus.

Serum IgG and IgA antibody responses to Campylobacter pylori in a group of healthy asymptomatic volunteers

Sera from 17 healthy asymptomatic volunteers were tested for presence of IgG and IgA antibodies against Campylobacter pylori and correlated with endoscopic biopsy findings. Three volunteers infected with C. pylori had the highest IgG antibody titers of the group. None of 14 C. pylori free subjects had significant IgG antibody levels. IgA antibody titers were negative in all subjects regardless of state of infection, in contrast to control sera from symptomatic C. pylori infected patients who manifested high IgA antibody levels.

The serodiagnosis of Campylobacter infection in infant cynomolgus monkeys (Macaca fascicularis) 2 to 18 weeks old by enzyme-linked immunosorbent assay

We established the enzyme-linked immunosorbent assay (ELISA) for detecting antibodies to Campylobacter and applied it in defining the period of the primary infection of Campylobacter in infant cynomolgus monkeys (Macaca fascicularis). The antibody to Campylobacter spp. could be detected with only 0.25 mul of serum by using commercially available antigens and anti-cynomolgus monkey IgG antibody conjugated with alkaline phosphatase. The inhibition experiments using extracts of C. jejuni, C. fetus and Yersinia enterocolitica demonstrated that the established ELISA system could detect species-specific anti-C. jejuni and anti-C. fetus antibodies. The levels of antibodies to both C. jejuni and C. fetus were high in 2 weeks old infant cynomolgus monkeys, rapidly decreasing until 6 to 14 weeks of age. This result indicates that the antibodies detected in 2 week old infants were IgG antibodies of maternal origin transferred through placenta. The C. jejuni was isolated from infants when the level of maternal antibody became the lowest. Infant cynomolgus monkeys obviously developed IgG antibodies to C. jejuni within 4 weeks after infection. On the other hand, no antibody response to C. jejuni was found in two infants from which it could not be isolated throughout the observation period. As regards C. fetus infection, infants showed a poor antibody response although it was more frequently isolated than C. jejuni. In conclusion, the ELISA system established in the present study is useful for the serological diagnosis of C. jejuni infection during infancy in the cynomolgus monkey.

Campylobacter pylori: clinical, histological, and serological studies

The presence of Campylobacter pylori, histologically diagnosed gastritis, and antibodies to C pylori were determined in a series of 113 patients undergoing endoscopy. Paired biopsy specimens from the fundus, body, and antrum were collected from 59 patients and from the antrum of 54 patients. The presence of C pylori was confirmed by either culture or silver stain in 30 of 59, 31 of 59, and 54 of 103 biopsy specimens from the fundus, body, and antrum, respectively. Of the specimens which contained C pylori 20 of 30 (66%) from the fundus, 25 of 31 (80%) from the body, and 54 (100%) from the antrum showed gastritis. C pylori and gastritis were shown in seven of nine (78.1%) of patients with gastric ulcers and in nine of 11 (82%) of patients with duodenal ulcers. Using an enzyme linked immunosorbent assay (ELISA) technique to detect IgG antibody to C pylori, all patients with histologically diagnosed gastritis and organisms present had titres of greater than or equal to 640; eight of 39 (21%) of patients without gastritis and without organisms gave similar titres. Hence the presence of C pylori was associated with gastritis and with raised titres of IgG antibody.

Relationship between Campylobacter pylori and gastritis in healthy humans after administration of placebo or indomethacin

Endoscopic and microscopic appearances of antral and fundic mucosa were correlated with the presence or absence of Campylobacter pylori--and with plasma immunoglobulin G antibodies to that organism--in 23 healthy volunteers, 12 of whom had received indomethacin and 11 of whom had received no medication. Antral C. pylori, found in 9 of 23 biopsy specimens (3 of 11 controls, 6 of 12 indomethacin-treated patients; not significantly different), correlated strongly with histologic evidence of active superficial antral gastritis (p less than 0.005), but not with the endoscopic appearance of the antrum. In contrast to the antrum, fundic C. pylori, found in 14 of 23 biopsy specimens (61%), were frequently associated with histologically and endoscopically normal fundic mucosa. Campylobacter pylori-associated active antral gastritis occurred only in subjects whose fundus harbored this organism. Plasma immunoglobulin G antibody titers to C. pylori were highest in subjects with Campylobacter-associated antral gastritis and lowest in subjects without gastric Campylobacter. These studies suggest that healthy humans may harbor C. pylori in their proximal stomach without apparent ill effects. In some of these individuals, the organism also involves the antrum and is associated with active gastritis.

Acute presentation of Campylobacter pylori gastritis

A 46-yr-old male was admitted to hospital with profuse vomiting, epigastric pain, and an infiltrative gastric lesion. Evidence is presented supporting the proposition that the symptoms were the product of an acute inflammatory response in the stomach induced by the bacterium Campylobacter pylori. The progress of the patient was monitored over a 2-yr period by endoscopic examination and serology for C. pylori. A significant rise in IgG antibody to C. pylori was seen only at 14 wk.

Immunoblot fingerprinting of Campylobacter pylori

One hundred and fifty isolates of Campylobacter pylori were divided into nine groups by immunoblot fingerprinting. All isolates were typable and reproducibility between immunoblots was good provided both antigen and antibody preparation were standardised. Discrimination was a problem as Groups 1 and 2 accounted for 66% of isolates. Recurrence after bismuth treatment was due to indistinguishable strains in five patients and different strains in three patients.

Antibacterial antibody pattern in seronegative spondyloarthropathies (SNSA)

The occurrence of some anti-bacterial antibodies was studied in sera from 31 healthy donors (HD) and 101 patients with different rheumatic diseases. The cases investigated included 7 Psoriatic Arthritis (PA), 35 Rheumatoid Arthritis (RA), 17 Undifferentiated Seronegative Spondyloarthritis (U-SNSA), 13 Behçet's syndrome, 18 Enteric Arthropathies (EA), 7 Ankylosing Spondylitis (AS) and 4 Reiter's syndrome. A complement fixation test was carried out to detect the presence and to evaluate the titer of the specific antibodies against the relative bacterial antigens. The antigens used were prepared for the complement fixation test by Virion Laboratories: Yersinia Enterocolitica 0:3 type (YEC), Yersinia Pseudotuberculosis (YPT), Campylobacter Jejuni (CJ) and Campylobacter Intestinalis (CI), Chlamydia Trachomatis (CT). The results indicate a statistically significant difference between the HD group and the seronegative polyarthritis one (PA, U-SNSA, Behçet, EA, AS, Reiter as a whole) as far as antibody production against YEC, CI and YPT is concerned. On the contrary, a significant difference between the HD group and RA patients for specific anti bacterial antibodies was only found against CT. Further detailed analysis of the behavior of the antibody pattern in any disease groups was carried out to identify a possible specific and featured antibody profile for some given rheumatic disorder.

Opsonophagocytosis of Campylobacter pylori

The opsonic activity of human serum from various sources against Campylobacter pylori was compared. All sera, whether from control subjects with no symptoms of gastritis or peptic ulceration, or from symptomatic patients from whom C. pylori had or had not been isolated, opsonised C. pylori equally well. Opsonisation depended on the alternative pathway of complement activation but not on antibody. These findings suggest that antibody plays no role in protection against C. pylori and that the presence of antibody in patients' sera is mainly of diagnostic value.

Campylobacter pylori in abattoir workers: is it a zoonosis?

Sera from 98 abattoir workers were tested for IgG to Campylobacter pylori, C jejuni, and klebsiella. Clerical workers had significantly lower C pylori and C jejuni IgG titres than any of the groups in direct contact with freshly cut animal parts. No difference was found for antibodies to klebsiella. 28 non-clerical workers with high-titre C pylori IgG consented to upper gastrointestinal endoscopy. C pylori associated gastritis was found in all 28, and four weeks of colloidal bismuth subcitrate (240 mg twice daily) was prescribed. On repeat testing at three months all showed a decrease in IgG titres to C pylori but not to C jejuni, whereas 18 untreated non-endoscoped workers showed no change. These findings raise the possibility that C pylori infection is a zoonosis.

Enzyme-linked immunosorbent assay for detection of immunoglobulin A and G antibodies to Campylobacter pylori

An enzyme-linked immunosorbent assay (ELISA) employing an acid-glycine extract was used to detect IgG and IgA antibodies to Campylobacter pylori in sera from 179 patients with upper gastrointestinal disease, 174 blood donors and 65 children. The incidence of positive ELISA results clearly increased with the severity of histopathologic findings in the antrum mucosa and was also high in patients with peptic ulcers and gastric cancer. The incidence in blood donors and children was much lower and increased with age. The results achieved with the ELISA were similar to those observed previously using the immunoblot method. Differences between whole cell preparation and acid-glycine extract with respect to their protein profiles and immunoblot reactivities were minor. IgM titres were very low and could not be related to histopathological findings, peptic lesions or culture findings. The ELISA may be particularly useful for monitoring the outcome of therapy aimed at eradication of Campylobacter pylori.

Comparison of different antigen preparations in an evaluation of the immune response to Campylobacter pylori

This study presents a novel approach to the analysis of protein antigens of Campylobacter pylori for use in serology. Protein fractions of this bacterium were resolved in polyacrylamide gel electrophoresis, eluted from gel strips in an electric field and used for coating of microtiter plates in an ELISA-type assay run with a small set of sera from both infected and non-infected patients. Reactivity and discriminative power of the different fractionated antigens (1-9) and crude antigen preparations (A-C) were compared. Better discrimination was achieved between positive and negative sera with high molecular weight fractionated preparations (antigens 8 and 9) than with low molecular weight fractions. Among the crude antigen preparations, antigens A (sonicated whole cells) and C (ultracentrifugated sonicate) seem to have a better discriminative power than antigen B (acid glycin extract).

Campylobacter pylori antibodies in humans

STUDY OBJECTIVE

To determine the diagnostic value of assays to measure serum antibodies to Campylobacter pylori, and to use these assays to determine the prevalence of C. pylori infection in a healthy population.

DESIGN

A survey of patients having endoscopies for upper gastrointestinal symptoms, patients with other gastrointestinal illnesses, and healthy controls.

SETTING

Outpatients attending endoscopy suites in two university-affiliated medical centers.

PATIENTS

One hundred and twenty patients who had gastroduodenoscopies, 61 patients with lower intestinal illnesses, and 166 healthy controls.

INTERVENTION

Assay to detect serum IgA, IgG, and IgM antibodies specific for C. pylori.

MEASUREMENTS AND MAIN RESULTS

Absorption with other gram-negative pathogens showed that IgG and IgA assays, but not IgM assays, were specific for C. pylori. In patients in whom C. pylori had been isolated and who had gastritis diagnosed by histologic methods, significantly higher mean IgA and IgG levels were seen compared with patients without demonstrable C. pylori or gastritis. The sensitivity and specificity of a positive value in both IgA and IgG assays were more than 93%. Among healthy persons, IgG and IgA antibodies were rarely seen in patients less than 20 years old, but antibody prevalence progressed with age, reaching 50% in patients more than 60 years old. High IgA and IgG levels to C. pylori in five persons tested remained stable for more than 1 year, suggesting the organism persists for at least that period. In 61 patients with acute bacterial enteritis, acute pancreatitis, Crohn disease, or ulcerative colitis, prevalence of antibodies to C. pylori was consistent with age and unrelated to current disease.

CONCLUSIONS

Campylobacter pylori infection, which is highly associated with active gastritis, may be diagnosed by serologic assay. Acquisition of infection begins in adult life, and prevalence increases with age.

Identification of an antigen common to different species of the genus Campylobacter

Affinity-purified antibody specific for a determinant on flagellin from Campylobacter jejuni was used to screen by immunoblotting strains of C. coli, C. laridis, C. fetus, "C. upsaliensis," C. pylori, and C. sputorum biovar fecalis. The antigen was detected in each of these species, but the molecular weights of the proteins bearing the common antigen varied considerably.

Antibody response to Campylobacter coli in children during intestinal infection and carriage

In the Central African Republic, etiological studies of diarrhea have shown that Campylobacter coli accounts for almost 40% of Campylobacter enteric isolations. This prompted us to investigate the antibody response to C. coli infection in children. As expected from the literature on Campylobacter jejuni infections, our results show that both infection and carriage elicited antibodies against glycine-extracted membrane antigens, flagella, and cholera toxin. The human antibody response to C. coli resembles the response to C. jejuni, and this similarity will allow comparative studies on larger numbers of infections, both symptomatic and asymptomatic. Anti-cholera toxin antibodies were directed against both the A and B subunits.

Serological diagnosis of the porcine proliferative enteropathies: implications for aetiology and epidemiology

Campylobacter mucosalis and C hyointestinalis have been associated with the proliferative enteropathies of pigs. An examination of the antibody response to these organisms and to the intracellular campylobacter-like organism was undertaken. Antibody to the campylobacter-like organism was predominantly IgM, short lived, and could be detected by an immunofluorescence test using bacteria released from lesions as antigen. The majority (75 per cent) of pigs with proliferative enteropathy at necropsy were antibody positive and a small number (4 per cent) of pigs in which lesions were not observed were found to have antibody. Antibody appeared to be correlated with the presence of lesions rather than with exposure to infection and was independent of the presence of antibody to C mucosalis or C hyointestinalis. In natural outbreaks of the disease antibody to the campylobacter-like organism was more prevalent than clinical signs in the affected animals.

Cytotoxic activity in broth-culture filtrates of Campylobacter pylori

Broth-culture filtrates of Campylobacter pylori induced non-lethal cytopathic effects in vitro in 7 of 9 mammalian cell lines tested. Transmission electronmicroscopy revealed that the response consisted of intracellular vacuolisation. Intestine 407 cells were among the most responsive and were used for routine assay. About 55% of isolates of C. pylori tested, originating from four geographic regions worldwide, produced cytotoxic activity. The activity was neutralisable by specific antisera to broth-culture filtrates or to sonicated bacteria but not by antisera to other bacterial preparations. Cytotoxic activity was heat-labile (70 degrees C for 30 min), was protease-sensitive and ammonium-sulphate precipitable. It did not pass through an ultrafiltration membrane with a nominal mol.-wt limit of 100 X 10(3). It was concluded that C. pylori can produce a factor that alters cultured cells in vitro. The relevance of this factor to the pathogenesis of gastritis associated with C. pylori remains to be determined.

Immunoblot analysis of immune response to Campylobacter pylori and its clinical associations

Systemic immune response to Campylobacter pylori was detected by the immunoblot technique in serum samples from 200 patients, 129 blood donors, and 96 children. The results of the IgG immunoblot test showed excellent correlation with the detection of C pylori by culture and also with histopathological examination of the antrum, as well as with peptic ulcer disease. An IgA response also occurred and gave results comparable with those of the IgG immunoblot test, although on a quantitatively lower scale. The IgM immunoblots were of no help in the serodiagnosis of C pylori infection. The protein bands that seemed to be the most specific for C pylori and which were consistently observed in patients positive for C pylori were a 110 kilodalton and a 63 kilodalton band on the IgG immunoblot and an 89 kilodalton band on the IgA immunoblot. A 94 kilodalton and a 28 kilodalton band were also included in the evaluation. While immunoblot analysis may be used effectively for the serodiagnosis of C pylori infection and can distinguish between patients with normal antrum mucosa and those with gastritis, the test does not help to distinguish between those patients with antrum gastritis who subsequently develop peptic ulcers and those who do not.

Influence of strain characteristics and immunity on the epidemiology of Campylobacter infections in Thailand

To determine how strain differences and immunity affect the clinical expression of Campylobacter infections, we conducted a study of acute diarrheal disease in Thailand in which specimens from children with Campylobacter infections were cultured weekly for up to 12 weeks to determine the serotype-specific length of time of convalescent-phase excretion and rate of reinfection. Levels of immunoglobulin G to cell-surface antigens of C. jejuni were determined in another population of healthy children who were closely related by age and location to the children in the diarrheal disease study. Campylobacter species were initially isolated from 18% of 586 children under 5 years old with diarrhea; most isolates in Thailand belonged to serotypes commonly found in developed countries. C. coli was significantly less often associated with symptomatic infections and with bloody diarrhea than C. jejuni (P less than 0.001 and P = 0.045, respectively). The peak age of isolation and the peak level of immunoglobulin G to Campylobacter species occurred before 2 years of age. The mean duration of convalescent-phase excretion was 14 +/- 2 (standard error of the mean) days for children less than 1 year old and 8 +/- 2 days for children 1 to 5 years old (P = 0.02, t test). Infection with another Campylobacter serotype was found in 34% of 105 children during the 12-week follow-up period. The rate of reinfection in these children was 15% (range, 8 to 22%) each week. Hyperendemic exposure to Campylobacter species in Thailand confers immunity to infection that is associated with an early peak in specific serum antibodies and an age-related decrease in the case-to-infection ratio and duration of convalescent-phase excretion but does not prevent asymptomatic infections.

Naturally occurring chronic gastritis and C pylori infection in the rhesus monkey: a potential model for gastritis in man

Histological examination of the stomachs of Rhesus monkeys at autopsy showed chronic gastritis in a high proportion of all ages. Lesions consisted of mild to heavy infiltration of the lamina propria by lymphocytes, plasma cells, and histiocytes. The antrum was most consistently affected, but lesions were also present in the fundus and pylorus. Gastric Campylobacter-like organisms (GCLO) apparently identical to human C pylori were cultured and/or detected immunohistologically in several animals. Electron microscopy showed the spiral bacteria on the epithelial surface and in gastric pits. They did not penetrate the cells but were intimately attached to the apical plasma membrane and caused loss of microvilli. Antibodies to C pylori were detected in serum of the monkeys by ELISA. The immunospecificity of this antibody response was confirmed by Western blotting techniques. A small number of cynomolgus monkeys examined had gastritis, which may also be associated with the presence of C pylori. Baboons did not have gastritis, nor was C pylori cultured from their stomachs. The study indicates that the Rhesus monkey has a naturally occurring gastritis associated with C pylori infection and may therefore be a suitable experimental animal for the human disease.

Antibody response of patients against a 120 kDa surface protein of Campylobacter pylori

Campylobacter pylori strains were isolated and serum samples were obtained from 63 patients. Immunoblots of 52 patients sera using their own isolates as antigen showed a 120 kDa band, which was missing in the other 11 isolates and the respective sera. This band was not detected in other Campylobacter species. Effects of trypsin treatment of bacteria and absorption of sera by live organisms suggest a C. pylori-specific surface protein.

[Campylobacter pylori, gastritis and ulcer disease. Microbiological, histological and serological studies]

In a prospective study of 70 patients with epigastric pain, gastroduodenoscopy revealed gastric and/or duodenal ulcers in a total of 41 and no ulceration in the remainder. Biopsies were taken to assess the severity of gastritis and the presence of Campylobacter pylori (CP) by histology and culture. Gastritis was found in 54 patients. CP was detected in 78% of the ulcer patients and 52% of the patients without ulcer (p less than 0.05). CP was demonstrated in 83% of the histologically diagnosed cases of gastritis (all grades) but no CP was detectable in patients with normal gastric mucosa. Among the ulcer patients, CP was more frequent in those with no history of medication with nonsteroidal antiinflammatory drugs (p less than 0.01). Sera from CP-positive ulcer and gastritis patients have significantly higher levels of IgG antibodies to CP than sera from those found to be free of ulcer or gastritis. In 200 blood donors an increasing percentage of elevated CP-antibody titres were found with advancing age (50% over 60 years of age). Quantification of circulating CP antibodies, would thus seem a valuable adjunct in the diagnosis of gastritis and probably also of peptic ulcer. The data presented furnish further evidence of the high rate of association of CP and the gastritis-peptic ulcer complex.

Lymphocytic gastritis--relationship to Campylobacter pylori infection

The existence of a distinctive form of chronic gastritis characterized by marked infiltration of the surface and pitlining epithelium by mature T lymphocytes has been confirmed. Seventeen cases were identified amongst 382 patients with active chronic gastritis (4.5 per cent). The cases with lymphocytic gastritis had significantly higher counts of intraepithelial lymphocytes than sex and age-matched controls drawn from a series of patients with the usual form of active Type B chronic gastritis. Furthermore, the lymphocytic gastritis group exhibited unusual endoscopic findings, namely erosions and 'raised lesions', in the body of the stomach. Such appearances have been previously described as 'varioliform' gastritis. Only seven of the patients (41 per cent) had C. pylori-positive biopsies, compared with over 90 per cent in the generality of active chronic gastritis, but all but two of the eleven cases tested had serological evidence of C. pylori infection. While the pathogenesis of this condition is unclear, the histological resemblance to coeliac disease suggests that lymphocytic gastritis might also represent an abnormal response to a local antigen to which the patient has become sensitized. It is possible that this antigen is C. pylori.

Campylobacter-like omega intracellular antigen in proliferative colitis of ferrets

Proliferative colitis in the ferret consistently displays, along with marked proliferation of mucosal cells, intracytoplasmic campylobacter-like organisms within the apical portion of the epithelial cells. Fluorescent antibody to "omega" campylobacter antigen present in porcine intestinal adenomatosis and hamster proliferative ileitis was demonstrated at the site of bacterial colonization within hyperplastic epithelial cells of six colons from ferrets affected with proliferative colitis.

Genomic rearrangements associated with antigenic variation in Campylobacter coli

Campylobacter coli and Campylobacter jejuni share a limited number of highly conserved DNA sequences with members of the family Enterobacteriaceae. One of these sequences was cloned from C. coli VC167, and the region of homology to the enteric sequences was determined to be confined to a 700-base-pair region. The DNA represented in this clone undergoes a programmed, reversible rearrangement in VC167 that is associated with flagellar antigenic variation.

Campylobacter pylori infection in children

Two children with antral nodular hyperplasia and active chronic gastritis associated with Campylobacter pylori are reported. The organism was observed by scanning electron microscopy and cultured from antral biopsies obtained at endoscopy from each patient. Anti-C. pylori IgG was detected in high titre in both patients together with serum IgM in one patient. Treatment with ampicillin and a bismuth preparation resulted in total resolution of symptoms. Repeated endoscopy with antral biopsy and culture, as well as the absence of acute inflammatory changes, confirmed the eradication of the organism. Correlation of positive bacteriological cultures and serological tests with the clinical improvement related to therapy supports a causative role for C. pylori in antral lymphoid hyperplasia and antral gastritis in children.

Antibody response to Campylobacter pylori in an ethnic group lacking peptic ulceration

The association between duodenal ulcer, gastritis and gastroduodenal colonization with Campylobacter pylori suggests a causal role for this newly described bacterium. In an attempt to challenge the verity of this association we studied a group of people in whom duodenal ulcer is apparently absent. Serological evidence of infection was sought with a sensitive, specific ELISA assay for C. pylori specific IgG and was compared with results from control sera from teenagers referred for respiratory viral serology, volunteer blood bank donors, patients with duodenal ulcers and patients in whom the presence or absence of C. pylori had been determined by histological and microbiological examination of gastric tissue. A relatively isolated group of Australian Aborigines in whom peptic ulceration is virtually unknown, was observed to possess age-specific mean C. pylori antibody levels comparable those found in a group of white Australian dyspeptic patients without microbiological evidence of infection with this organism. The antibody levels of Aborigines were lower than those found in an aged-matched group of 'healthy' white Australians, both of these groups having levels which were significantly lower than the levels found in culture positive white Australian dyspeptic patients. It was found that 21/144 'healthy' white Australians (14.6%) had antibody levels greater than or equal to the lower 99% confidence interval of the mean level found in culture positive patients, while only 2/274 Aborigines (0.7%) had such elevated levels. By contrast, 89/142 (62.7%) patients with endoscopically proven duodenal ulcer had similarly elevated specific antibody levels. These differences were highly significant. We consider these findings to be consistent with the hypothesis that C. pylori is important in the pathogenesis of duodenal ulcer.

An enzyme-linked immunosorbent assay for the serodiagnosis of Campylobacter pylori-associated gastritis

An ELISA system, using an acid extractable cell surface C. pylori antigen, has been used to detect anti-C. pylori antibodies in 176 endoscoped patients. The antibody concentration was related to histological diagnosis and colonisation with Campylobacter-like organisms. The criteria for sero-positivity was determined from the median antibody concentration in a group of 368 non-endoscoped control patients. The specificity and sensitivity of the sero-diagnostic assay for histological gastritis in antral biopsies was 83.0% and 95.6% respectively. The positive (79.3%) and negative predictive values (94.3%) indicate that such a sero-diagnostic assay could be used to screen patients prior to endoscopy.

Antibody response to Campylobacter pylori in diverse ethnic groups

Antibody response to Campylobacter pylori was measured in ethnic groups of Vietnamese, El Salvadorean and Ethiopian origin. The results were compared with the previously reported antibody titres found in sera of culture positive and culture negative patients, patients suffering from duodenal ulcer, white Australian blood donors and Australian Aboriginals. While in Vietnamese the prevalence of serologically positive sera was found to be similar to the white Australian population, numbers of serologically positive sera in El Salvadorean and Ethiopian ethnic groups was found to be very high. The high incidence of serologically positive sera in the Ethiopians correlated with the reported high incidence of duodenal ulcer in this population.

Antigenic variation of Campylobacter flagella

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of flagella dissociated from strains of Campylobacter coli and Campylobacter jejuni belonging to the heat-labile serogroup LIO 8 showed that some strains were capable of producing flagellin subunits of two different molecular weights (MrS), 59,500 and 61,500. Immunoelectron microscopy of cultures of the type strain of this serogroup, C. coli VC167, showed the presence of two flagellum filaments of different antigenic specificity. Epitopes on the surface of one of these flagella bound antibodies in LIO 8 typing antiserum, and Western blotting (immunoblotting) and immunoprecipitation showed that the flagellum was composed of flagellin of Mr 61,500. The other flagellum antigenic type did not bind LIO 8 antibodies but did possess serospecific epitopes which bound a second polyclonal antiserum, LAH2. This second antigenic flagellum type was composed of the Mr 59,500 flagellin. Cells producing either of the flagellum antigenic types serotyped as LIO 8, indicating that flagella composed of the Mr 61,500 flagellin do not carry the serological determinants for this serogroup. The ability of C. coli VC167 to produce these flagella of different subunit MrS was shown to represent a bidirectional antigenic variation. When measured in culture medium, the phase 1-to-phase 2 transition occurred at a rate of approximately 2.0 x 10(-5) per cell per generation, and the phase 2-to-phase 1 transition occurred at a rate of 1.2 x 10(-6) per cell per generation.

Single and multiple acid extract antigens in Campylobacter serology

Campylobacter IgA, IgM and IgG antibody titers of 442 patients with positive isolations of Campylobacter were tested in enzyme immunoassay (EIA). Of the patients, 330 showed elevated antibody end-point titers to a single acid extract antigen prepared from a C. jejuni strain. Sixteen further patients had fourfold or greater antibody titer changes in paired sera. Nine patients, who did not show elevated antibody titers for the single extract, had positive serological responses for a multiple acid extract prepared from six C. jejuni/coli and a C. fetus subsp. fetus strain. The specificity of the test, based on Campylobacter antibodies of 200 healthy blood donors, was 99%. The use of the single acid extract gave a sensitivity of 78%. The additional use of the multiple acid extract raised the sensitivity to 80%.

Campylobacter etiology in human gastroenteritis demonstrated by antibodies to acid extract antigen

Campylobacter antibodies of the immunoglobulin G (IgG), IgM, and IgA classes were determined by enzyme immunoassay with acid glycine extract antigen in patients and controls involved in two Campylobacter outbreaks and in 266 unselected patients with acute enteritis. The assay showed a specificity of 99% for each immunoglobulin class in sera from 200 healthy blood donors. Elevated Campylobacter antibody titers were shown in 97% of stool culture-positive patients involved in the outbreaks. Rapid changes of IgA and IgM Campylobacter antibodies were typical of the early phase of serologic response in the outbreaks and thus offered the best diagnostic value in the serologic diagnosis of acute campylobacteriosis. In unselected patients with acute enteritis, the assay revealed elevated Campylobacter antibody titers in 37 patients, of whom only 12 had had positive Campylobacter stool cultures. In the sera of patients with other bacterial findings in addition to high titers of Campylobacter antibodies, no cross-reacting antibodies were found, but there was evidence of several mixed infections.

Frequency of occurrence of Campylobacter pylori and analysis of the systemic and local immune response

During gastroduodenoscopic examination of 225 patients, bioptic mucosal specimens were taken for bacteriological and histological examination (Table 1). Campylobacter (C.) pylori was isolated from 7 out of 9 patients (78%) with gastric ulcer, from 59 out of 60 (98%) with duodenal ulcer, from 24 out of 31 (77%) with gastric erosions, from 10 out of 10 (100%) with duodenitis, from 14 out of 16 (88%) with chronic active gastritis, from 40 out of 73 (55%) with chronic inactive gastritis and from none out of 26 patients (0%) with normal mucosa (Table 2). To study the immune response an ELISA was developed which proved to give well reproducible and specific test results (Fig. 1). IgA- and IgG-titres were strongly reduced after absorption with C. pylori, but not with other antigens (including C. jejuni and C. coli, Table 3). Some sera gave reactions at higher titres when tested with the patient's own strain than with the standard antigen which is a mixture of 4 strains (Table 4). This indicates differences of the antigen composition within the species C. pylori. Sera from patients with positive culture showed higher IgG- and IgA-titres than sera from patients without isolation of C. pylori. The IgM-titres, however, were comparable in both groups (Fig. 3). Partially, sera from patients without C. pylori also showed high IgG-titres which were positively correlated with the patient's age. About 60% of culturally positive patients had specific IgA in their gastric juice, whereas this was not so with patients without isolation of C. pylori (Fig. 6). Examination of sera from healthy children and blood donors revealed that IgG but not IgA or IgM rose significantly with increasing age (Figs. 7-9). As can be concluded from the results of cultural and serological tests, C. pylori seems to be responsible at least for a part of cases of gastritis and peptic ulcer.