An immunological study of coeliac disease and idiopathic steatorrhoea. Serological reactions to gluten and milk proteins

Celiac Disease and Neurological Manifestations: From Gluten to Neuroinflammation

Celiac disease (CD) is a complex multi-organ disease with a high prevalence of extra-intestinal involvement, including neurological and psychiatric manifestations, such as cerebellar ataxia, peripheral neuropathy, epilepsy, headache, cognitive impairment, and depression. However, the mechanisms behind the neurological involvement in CD remain controversial. Recent evidence shows these can be related to gluten-mediated pathogenesis, including antibody cross-reaction, deposition of immune-complex, direct neurotoxicity, and in severe cases, vitamins or nutrients deficiency. Here, we have summarized new evidence related to gut microbiota and the so-called "gut-liver-brain axis" involved in CD-related neurological manifestations. Additionally, there has yet to be an agreement on whether serological or neurophysiological findings can effectively early diagnose and properly monitor CD-associated neurological involvement; notably, most of them can revert to normal with a rigorous gluten-free diet. Moving from a molecular level to a symptom-based approach, clinical, serological, and neurophysiology data might help to disentangle the many-faceted interactions between the gut and brain in CD. Eventually, the identification of multimodal biomarkers might help diagnose, monitor, and improve the quality of life of patients with "neuroCD".

Review article: Diagnosis of coeliac disease: a perspective on current and future approaches

Diagnostics will play a central role in addressing the ongoing dramatic rise in global prevalence of coeliac disease, and in deploying new non-dietary therapeutics. Clearer understanding of the immunopathogenesis of coeliac disease and the utility of serology has led to partial acceptance of non-biopsy diagnosis in selected cases. Non-biopsy diagnosis may expand further because research methods for measuring gluten-specific CD4+ T cells and the acute recall response to gluten ingestion in patients is now relatively straightforward. This perspective on diagnosis in the context of the immunopathogenesis of coeliac disease sets out to highlight current consensus, limitations of current practices, gluten food challenge for diagnosis and the potential for diagnostics that measure the underlying cause for coeliac disease, gluten-specific immunity.

Emergence of an adaptive immune paradigm to explain celiac disease: a perspective on new evidence and implications for future interventions and diagnosis

INTRODUCTION

Recent patient studies have shown that gluten-free diet is less effective in treating celiac disease than previously believed, and additionally patients remain vulnerable to gluten-induced acute symptoms and systemic cytokine release. Safe and effective pharmacological adjuncts to gluten-free diet are in preclinical and clinical development. Clear understanding of the pathogenesis of celiac disease is critical for drug target identification, establishing efficacy endpoints and to develop non-invasive biomarkers suitable to monitor and potentially diagnose celiac disease.

AREAS COVERED

The role and clinical effects of CD4+ T cells directed against deamidated gluten in the context of an "adaptive immune paradigm" are reviewed. Alternative hypotheses of gluten toxicity are discussed and contrasted. In the context of recent patient studies, implications of the adaptive immune paradigm for future strategies to prevent, diagnose, and treat celiac disease are outlined.

EXPERT OPINION

Effective therapeutics for celiac disease are likely to be approved and necessitate a variety of new clinical instruments and tests to stratify patient need, monitor remission, and confirm diagnosis in uncertain cases. Sensitive assessments of CD4+ T cells specific for deamidated gluten are likely to play a central role in clinical management, and to facilitate research and pharmaceutical development.

Diagnosis and management of adult coeliac disease: guidelines from the British Society of Gastroenterology

A multidisciplinary panel of 18 physicians and 3 non-physicians from eight countries (Sweden, UK, Argentina, Australia, Italy, Finland, Norway and the USA) reviewed the literature on diagnosis and management of adult coeliac disease (CD). This paper presents the recommendations of the British Society of Gastroenterology. Areas of controversies were explored through phone meetings and web surveys. Nine working groups examined the following areas of CD diagnosis and management: classification of CD; genetics and immunology; diagnostics; serology and endoscopy; follow-up; gluten-free diet; refractory CD and malignancies; quality of life; novel treatments; patient support; and screening for CD.

Diagnostic utility of modified gliadin peptide antibody assays in New Zealand children

OBJECTIVE

The aim of the present study was to evaluate a panel of different antibody assays, including second-generation antigliadin kits, in a local paediatric population thought to be at risk for coeliac disease (CD).

METHODS

Seventy-nine children, who tested positive for immunoglobulin A (IgA) antibodies to tissue transglutaminase (TG), underwent duodenal biopsy. At endoscopy, serum was collected from all of the patients, and 9 different coeliac antibody assays were performed, both as isolated assays and in combination. These included immunoglobulin A (IgA) anti-tissue transglutaminase (TGA), and IgA plus IgG anti-deamidated gliadin peptide (DGPAG). A diagnosis of CD was made if the biopsies showed Marsh grade 3 lesions.

RESULTS

Twenty-four of 79 children had CD confirmed histologically. Only 39 of 79 were positive for Inova TGA, and 35 of 79 were positive for Inova DGPAG. Twenty-four of 39 who were TGA positive and 24 of 35 who were DGPAG positive had confirmed CD on biopsy. There was good correlation between TGA and DGPAG-positive predictive values. None of the modified gliadin tests produced false-negative results, and neither did the TGA.

CONCLUSIONS

The Inova DGPAG and TGA assays have similar use in predicting CD in a selected paediatric population; however, in children who are positive for TGA when screened for CD, more than half have negative TGA serology when repeat testing is done at the time of biopsy. Those with persistent TGA positivity have only a 61.5% probability of having histologic CD, compared with 68.6% of those children positive for DGPAG.

[Serological diagnosis of celiac disease]

Screening studies using high-sensitivity and specificity markers indicate a prevalence of celiac disease of up to 1% in European and North-American populations. Celiac disease is a frequent condition that has become an important public health issue. Yet the majority of cases remain undiagnosed due to the polymorphism of its clinical manifestations. The new insight in the pathogenesis of celiac disease has lead to the development of new diagnostic tools. Early screening of symptomatic patients and pre-identified at-risk groups significantly improves the quality of life while reducing morbidity and mortality. However, prophylactic benefits of early diagnosis by assessing the general population have not been shown in any study. French and Northern American scientific societies have introduced serological testing in their newly revised strategies to diagnose celiac disease. Older markers judged insufficiently accurate like anti-gliadin and anti-reticulin antibodies have recently been withdrawn from the list of reimbursed medical expenses in France. Anti-endomysium and tissue transglutaminase IgA antibodies have proven to be at this day the most sensitive and specific markers for the diagnosis and follow-up of patients on gluten-free diet, at the exception of IgA-deficient patients. Assays testing for IgG antibodies are recommended upon IgA-deficiency. Although very accurate, a better standardisation of current assays may enable serological testing to replace in a near future histological confirmation brought by small bowel biopsies which remains today the gold standard test to diagnose celiac disease. Indeed, serological testing represents and attractive alternative as it is less invasive, less expansive, laboursaving and more objective in interpretation.

Determining IgA and IgG antigliadin, IgA antitransglutaminase, and antiendomysial antibodies in monkey esophagus and in umbilical cord for diagnosis of celiac disease in developing countries

OBJECTIVES

To assess the efficiency of determining IgA and IgG antigliadin antibodies (IgA- and IgG-AGA, respectively), antitransglutaminase (TgA), and anti-endomysial antibodies (AEA) in human umbilical cord (CO) and monkey esophagus for diagnosis of celiac disease; to determine the correlation between serological markers and celiac disease.

PATIENTS AND METHODS

A total of 400 patients were divided in 3 groups: group 1 with 37 patients with celiac disease, group 2 with 208 patients with no enteropathies, and group 3 with 155 patients with other enteropathies. IgA-AGA, IgG-AGA, and TgA were assessed using enzyme-linked immunosorbent assay, whereas AEA was evaluated by indirect immunofluorescence.

RESULTS

Sensitivity and specificity of IgA-AGA were 81.1% and 95.2%, of IgG-AGA 89.2% and 95.2%, of TgA 83.9% and 96.8%, of AEA-CO 87.9% and 100%, and of AEA of monkey esophagus 88.6% and 100%, respectively. Positive predictive values were 75.0%, 76.7%, 83.9%, and 100%. Negative predictive values were 96.6%, 98.0%, 96.8%, and 97.7% for IgA-AGA, IgG-AGA, TgA, and AEA, respectively. Multivariate analysis showed a strong association between AEA-CO and celiac disease and a good correlation with other markers (TgA, IgA-AGA, and IgG-AGA).

CONCLUSIONS

TgA has been recommended for screening patients with celiac disease. Considering the similar sensitivity and specificity of IgA-AGA and TgA and their correlations in the multivariate analysis, both are applicable for this purpose. However, because TgA tests are highly costly and celiac disease is associated with IgA deficiency, the determination of IgA-AGA and IgG-AGA, followed by AEA-CO, is suitable for screening in developing countries, provided a cutoff point for these examinations is established. The results of antiendomysial antibodies in umbilical cord overlapped those in monkey esophagus. Therefore, umbilical cord should be used as a substrate instead of specimens from endangered species.

Cutaneous manifestations in celiac disease

Celiac disease (CD) is an autoimmune gluten-dependent enteropathy characterized by atrophy of intestinal villi that improves after gluten-free diet (GFD). CD is often associated with extra-intestinal manifestations; among them, several skin diseases are described in CD patients. The present review reports all CD-associated skin manifestations described in the literature and tries to analyze the possible mechanisms involved in this association. The opportunity to evaluate the possible presence of CD in patients affected by skin disorders is discussed.

Serum antigliadin antibody levels as a screening criterion before jejunal biopsy indication for celiac disease in a developing country

The objective of the present study was to determine the efficacy of detection of antigliadin immunoglobulins G and A (IgG and IgA) for the diagnosis of celiac disease in a developing country, since other enteropathies might alter the levels of these antibodies. Three groups were studied: 22 patients with celiac disease (mean age: 30.6 months), 61 patients with other enteropathies (mean age: 43.3 months), and 46 patients without enteropathies (mean age: 96.9 months). Antigliadin IgG and IgA ELISA showed sensitivity of 90.9 and 95.5%, respectively. With the hypothetical values of prevalence ranging from 1:500 to 1:2000 liveborns, the positive predictive value varied from 8.5 to 2.3% for IgG and from 4.8 to 1.1% for IgA. Considering the patients without enteropathies, specificity was 97.8 and 95.7% for IgG and IgA, respectively. In patients with other enteropathies, specificity was 82.0 and 84.1%, respectively. When patients with and without other enteropathies were considered as a whole, specificity was 88.8 and 91.6%, respectively. The specificity of positive IgG or IgA was 93.5% in children without enteropathies and 78.7% in the presence of other enteropathies. The negative predictive value for hypothetical prevalences varying from 1:500 to 1:2000 liveborns was 99.9%. Thus, even in developing countries where the prevalence of non-celiac enteropathies is high, the determination of serum antigliadin antibody levels is a useful screening test prior to the jejunal biopsy in the investigation of intestinal malabsorption.

Biochemical tests in diseases of the intestinal tract: their contributions to diagnosis, management, and understanding the pathophysiology of specific disease states

Biochemical testing plays a major role in the complete evaluation of patients with suspected or established intestinal disease. We have classified these tests according to the medium in which they are performed: breath tests, including isotopic and nonisotopic tests, fecal tests, urine tests, serum tests, tissue tests, and other tests. The principles of various tests are outlined, and the role of each test in the evaluation of particular gastrointestinal disorders is discussed.

Antigliadin antibody measurement by chemiluminescence ELISA in the diagnosis of coeliac disease

AIMS

To develop a chemiluminescence enzyme linked immunosorbent assay (ELISA) for the detection of circulating gliadin antibodies in the diagnosis of coeliac disease. To compare this method for linearity and sensitivity with an established colorimetric method.

METHODS

Three sets of age and sex matched patient groups were studied: normal controls (patients with no clinical signs of intestinal disorders); gastrointestinal controls (patients with a known gastrointestinal disorder other than coeliac disease); and patients in whom suspected coeliac disease had been confirmed by positive jejunal biopsy. IgG antigliadin antibody (IgG-AGA) and IgA antigliadin antibody (IgA-AGA) titres were determined.

RESULTS

Comparison of the colorimetric and chemiluminescence methods showed close correlation of measured antibody levels for both control patient groups. In the coeliac patients correlation of antibody levels measured by both methods was not possible because the colorimetric assay is limited by the spectrophotometer's limits of detection. This problem was overcome by the chemiluminescence method which was linear over a greater range and to far higher values.

CONCLUSIONS

The chemiluminescence ELISA performs as well as the colorimetric assay at low and average antibody levels and has the advantage of also giving a numerical value to higher antibody titres. The method was accurate and reproducible in confirming the diagnosis of coeliac disease in patients with positive jejunal biopsy and was capable of monitoring progress of the disease.

Gluten specific suppressor T cell dysfunction in coeliac disease

A T lymphocyte direct migration inhibition factor test has been used to investigate the function of the specific suppressor T cell population controlling the immune response to gluten in coeliac disease. The test has been carried out in 21 adult coeliac patients, 22 Mantoux- healthy controls and eight Mantoux+ donors using gluten fraction III and purified protein derivative, as antigens. All coeliacs, but two, were Mantoux-. When gluten fraction III was used a significant migration inhibition was observed in coeliac patients compared to controls; such migration inhibition was abrogated by coculturing in a 1:1 ratio coeliac T cells with T cells from controls or Mantoux+ donors. On the contrary, the addition to coeliac T cells of T lymphocytes from other coeliacs did not abolish migration inhibition to gluten. Pretreatment of normal T cells with mitomycin C prevented their abrogating activity on migration inhibition of coeliac T lymphocytes. When purified protein derivative was used as antigen a significant migration inhibition was observed in Mantoux+ donors compared with healthy subjects and such migration inhibition was abolished by co-culturing T cells from Mantoux+ donors with those from Mantoux- controls and coeliac patients. Our results show that coeliac T cells, while retaining their ability to suppress the immune response to purified protein derivative, cannot suppress the immune response to gluten and are consistent with the hypothesis that a gluten specific suppressor T cell dysfunction, rather than a generalised T lymphocyte defect, may play a role in the pathogenesis of coeliac disease.

Specific IgG subclass antibodies, IgE and IgG S-TS antibodies to wheat gluten fraction B in patients with coeliac disease

Antibodies were measured in the sera of fifteen patients with untreated coeliac disease and twenty-eight patients with inflammatory bowel disease. Increased levels of specific IgG, IgG1, IgG2, and IgG4 antibody to wheat gluten fraction B, measured by an enzyme-linked immunosorbent assay, were shown in the coeliac disease group, but not in the inflammatory bowel disease group. No specific IgE antibody to fraction B was detected but 33% of the patients with coeliac disease had specific short-term sensitizing (anaphylactic) IgG antibody activity (IgG S-TS) to fraction B. There was no correlation between the IgG2 or IgG4 specific antibody and the presence of IgG S-TS activity.

A solid-phase radioimmunoassay for IgG gliadin antibodies using 125I-labelled staphylococcal protein A

A sensitive radioimmunoassay for IgG gliadin antibodies is described. Serum specimens were added to wells of plastic microtitre plates coated with gliadin. After removal of the unbound material, gliadin antibodies were detected by adding 125I-labelled staphylococcal protein A (125I-SpA). Serum specimens from coeliac patients on a normal diet or on a gluten-free diet were tested, as well as sera from an age-matched control group. Measurements to obtain precise quantitative values were made with gliadin antibody-rich serum as reference standard. High titres of gliadin antibodies were found in 18 out of 19 coeliac patients on a normal diet (95%); in patients on a strict gluten-free diet serum values did not exceed 2 S.D. of the control mean. Due to the high sensitivity of the method a low but detectable amount of gliadin antibody was present in the sera of all controls.

A solid-phase radioimmunoassay for measurement of circulating antibody titres to wheat gliadin and its subfractions in patients with adult coeliac disease

A solid-phase radioimmunoassay for the measurement of circulating antibody titres to wheat gliadin is described. Using this assay, we have measured antibody titres to unfractionated gliadin in normal healthy controls, in coeliac patients on a gluten-free or a normal diet, and in patients with ulcerative colitis and Crohn's disease. High titres of antibodies to unfractionated gliadin were observed only in the patients with untreated coeliac disease. Antibody titres to alpha, beta, gamma and omega gliadin subfractions were measured in patients with untreated coeliac disease and compared with titres in normal controls. Patients with untreated coeliac disease had higher antibody titres to the gliadin subfractions. No specific pattern of circulating antibody titres to gliadin subfractions was observed in the untreated coeliac patients which would provide a diagnostic profile. These results suggest shared antigenicity between the gliadin subfractions.

Intestinal absorption of food antigens in coeliac disease

Serum concentrations of ovalbumin, beta-lactoglobulin, and antigen-antibody complexes were measured after jejunal administration of milk and raw egg in 6 children with active coeliac disease and in 4 controls. The results did not support the hypothesis of a generalised increase in absorption of antigens from the intestinal lumen in coeliac disease.

IgA anti-gliadin antibodies in coeliac disease

Sixty-two sera from children under investigation for gastrointestinal disease were tested for IgA, IgG and IgM antibodies to gliadin by two different methods: an immunofluorescent (IF) test, and a mixed reverse (solid-phase) passive antiglobulin haemadsorption (MRSPAH) test. There was good agreement between the tests. Both tests detected gliadin antibodies of IgG and IgA class in sera from children with active coeliac disease, which tended to disappear when a strict gluten-free diet was instituted. Serum antibodies to gliadin of IgA class were associated with severe small intestinal villous atrophy and were found almost exclusively in coeliac disease. Gliadin antibodies of IgG class were less disease-specific and were occasionally detected in sera from children with gastrointestinal disease other than coeliac disease--notably in sera from children with transient gluten intolerance.

Cutaneous vasculitis complicating coeliac disease

A 38 year old female, with chronic uncontrolled coeliac disease, presented with the rare complication of cutaneous leucocytoclastic vasculitis. Detailed study failed to identify any cause for the vasculitis, other than the underlying coeliac disease. Haematuria and proteinuria with mesangial nephritis were also demonstrated on renal biopsy with electron microscopic study. It is speculated that exogenous or endogenous antigens permeated the abnormal small bowel mucosa leading to formation of circulating immune complexes. Subsequent tissue deposition of these complexes then resulted in vasculitis and nephritis. The skin lesions cleared completely after treatment with a strict gluten free diet.

Inhibition of rat intestinal anaphylaxis by various anti-inflammatory agents

Adverse reactions to food may, in some cases, be due to IgE-mediated immune reactions to the ingested antigens. A mast cell protector has been shown to protect patients against challenge with food to which they are sensitive. An IgE-mediated intestinal anaphylaxis reaction in the rat has been developed as a model of some aspects of human food allergy. Using this model, a number of xanthones and other anti-inflammatory agents were tested for activity in inhibiting intestinal anaphylaxis. The compounds were also tested for inhibitory activity against the IgE-mediated rat passive cutaneous anaphylaxis reactions. The xanthones protected against both reactions, as did isoproterenol and cyproheptadine, while aspirin, indomethacin, and dexamethasone inhibited the intestinal but not the cutaneous reaction. This suggests that while IgE-triggered mediator release from mast cells is important in both reactions, other mechanisms may also be operative in the intestinal reaction. Furthermore, the use of xanthones and other anti-inflammatory compounds may be a useful mode of therapy in human food allergy.

Coeliac disease associated with recurrent aphthae

Fifty patients presenting sequentially with a history of recurrent aphthae were investigated for evidence of nutritional deficiencies and coeliac disease. In the group, two patients were found to have coeliac disease and their recurrent aphthae cleared soon after starting a gluten free diet. This study confirms the presence of an increased prevalence of nutritional deficiency and of coeliac disease in aphthous patients. However, it is recommended that jejunal biopsy be carried out in these cases only where there is evidence of malabsorption.

Wheat protein antibodies in dermatitis herpetiformis

An enzyme-linked immunosorbent assay was used to detect class-specific antibodies to wheat protein antigens. Antibodies which we detected by this technique reacted indistinguishably with antigens prepared from crude gluten, crude gliadin, alpha-gliadin, Frazer fraction III, and subfraction B and B3 of Frazer fraction III. No sera reacted with a human serum albumin control antigen. The prevalence of IgG antibodies to wheat protein antigens was significantly greater in patients with gluten sensitive enteropathy, 12 of 17, (p = .00011) and in patients with dermatitis herpetiformis, 5 of 14, (p = .046) than in normal control subjects. Strongly positive reactions for IgG antibodies were present only in patients with gluten sensitive enteropathy or dermatitis herpetiformis. IgA antibodies to wheat protein antigens were found only in gluten-sensitive enteropathy patients. We have found this to be a sensitive, precise technique for measurement of antibodies to wheat protein antigens and feel that it will prove useful in evaluation of the role of immune complexes involving wheat protein antigens and their antibodies in the pathogenesis of dermatitis herpetiformis.

Immunofluorescent serum gliadin antibodies in children with coeliac disease and various malabsorptive disorders. I. Technique, clinical evaluation and diagnostic use of a gliadin antibody assay using pyruvic aldehyde-treated human red cells

An immunofluorescent gliadin antibody assay is described using pyruvic aldehyde-stabilized human erythrocytes coated with gliadin. Fifty coeliac children all had high serum IgG-antigliadin titres during a normal diet or a challenge with gluten. On a gluten-free diet (30 children), titres were much lower. In patients followed-up for one year on a gluten-free diet, an initial rise in titres was followed by a slow decline. On challenge, IgG-antigliadin titres showed a slow rise or persistence at the same level in most patients. Fifty-two percent of control children with malabosrptive disorders, but without the typical "flat" mucosal lesion on jejunal biopsy, were shown to have positive titres in their sera, as were 6% of normal children and 4% of adult blood donors. The fluorescent antibody technique was compared with methods commonly used to detect wheat-protein antibodies, and was found to be superior to all of them. The immunofluorescent gliadin antibody assay appears to be useful in following-up children with coeliac disease, and in selecting patients for jejunal biopsy, although it does not replace biopsy.

Antibodies to gluten and reticulin in gastrointestinal diseases

Antibodies to reticulin were found in 33% of coeliac patients on a normal diet. These antibodies were found in only 11% of coeliac patients on a gluten-free diet. In patients with dermatitis herpitiformis, 12% had these antibodies, whereas the highest frequency in the other diseases studied (Crohn's disease, ulcerative colitis, cystic fibrosis and `recurrent diarrhoea') was 7% (compared to 2% in healthy controls).

Antibodies to gluten, demonstrated with the immunofluorescence technique, were found in all coeliac children on a normal diet that were studied, and in half of the adults with the untreated disease. In children and adults on a gluten-free diet these frequencies decreased to 87 and 32%. In Crohn's disease, cystic fibrosis, recurrent diarrhoea, dermatitis herpetiformis and ulcerative colitis, the frequencies were 52, 42, 37, 18 and 18%, respectively (and in 4% of controls).

It was therefore concluded that antibodies to gluten were sensitive markers for gastrointestinal diseases, but were not specific for gluten enteropathy. Antibodies to reticulin, on the other hand, were less sensitive but of far greater specificity for coeliac disease. Gluten antibodies were of the IgA, IgM and IgG classes, whereas antibodies to reticulin were only of the IgA and IgG classes. Both types of antibody were found to be non-complement-fixing. Autoantibodies to smooth muscle were found in 5% of the coeliac patients (and in 0% of controls). No relationship with hepatic complications was found. In the patients with dermatitis herpetiformis, autoantibodies to gastric parietal cells were found in 24% (and in 5% of controls). No relationship was established between the occurrence of HLA-B8 and the presence or absence of any of the antibodies studied.

[Antireticulin antibodies and precipitating antibodies to food proteins in the sera of children with coeliac disease (author's transl)]

Sera from 41 children suffering with histologically proven coeliac disease and from 40 healthy control children were investigated for the presence of antireticulin antibodies and precipitating antibodies to a watery extract of wheat flour and to cow's milk. Antireticulin antibodies were demonstrated by means of indirect immunofluorescence using sections of fresh rat kidney as substrat. For the detection of precipitating antibodies a combination of electrophoresis and immunodiffusion was used. Serum antireticulin antibodies were found in 11/13 children (85%) with active coeliac disease, in 7/17 children (41%) with clinically and biochemically silent coeliac relapse and in 0/16 children with treated coeliac disease. Serum precipitating antibodies to wheat flour and cow's milk were found respectively in 3/13 children (23%) and 2/13 children (15%) with active coeliac disease and in 1/16 children (6%) with treated coeliac disease. Precipitating antibodies could not be detected in the sera of 17 patients with silent relapse of coeliac disease. In the sera of 40 controls neither antireticulin nor precipitating antibodies were detectable. The presence of antireticulin antibodies in serum did not correspond to the presence of serum precipitins to wheat flour and cow's milk. The significance of serum antireticulin antibodies for screening investigations and for follow-up studies is discussed.

Atopic disorders and adult coeliac disease

A history of asthma, hay fever, and flexural eczema was significantly more common in patients with adult coeliac disease (A.C.D.) than in normal controls. Autoantibodies were also more common in A.C.D. First-degree relatives of A.C.D. patients were more likely than controls to have atopic disorders. A deficiency of local mucosal immunity due to abnormal IgA responses may underly this association between A.C.D. and atopy.

Anti-reticulin antibody in jejunal juice in coeliac disease

Anti-reticulin antibody has been demonstrated in the jejunal juice of eight out of fourteen (57%) untreated coeliac patients, one out of twelve (8%) patients with normal jejunal biopsies and none of ten normal control subjects. The jejunal juice antibody was invariably of the IgA class. It is suggested that the presence of anti-reticulin antibody in the jejunal juice in coeliac disease supports the hypothesis that this antibody is secreted in response to reticulin antigens present in the diet.

The effect of different feeds, including those containing soya-bean products, on the passage of digesta from the abomasum of the preruminant calf

1. The effects of various factors on rates of flow and composition of digesta leaving the abomasum of preruminant calves were studied. The possible relation of some of these effects to the development of serum antibodies to certain dietary constituents has also been examined. Two situations were distinguished: (a) unsensitized responses, shown by calves receiving milk protein or soya-bean products for the first one or two occasions; (b) sensitized responses, shown by calves receiving certain soya-bean products, after a number of these feeds had been given. 2. For unsensitized calves, the rate of flow of total digesta from the abomasum was greater in the first few hours after a feed consisting of a mineral solution was given, than after cow's milk was given. This difference wasapparently due to differences in the composition of digesta entering the duodenum. Total digesta flows after giving synthetic milk feeds, prepared from different protein sources, were similar to those after cow's milk was given. 3. For sensitized calves, rates of flow of total digesta from the abomasum were greatly affected by the nature of the protein source used in the diet. Soya-bean flour (heated or unheated) generally caused inhibition of flow for some hours after feeding; a soya-bean protein isolate (isoelectric) had a similar but smaller effect, but a soya-bean concentrate (prepared by alcohol extraction of a soya-bean flour) and milk protein had little or no effect. The inhibition, believed to be a sign of more general disorders, appeared to be caused by a factor entering the duodenum which induced a change in the way in which the calf responded, probably as the result of a gastrointestinal allergy. 4. Calves given soya-bean flour or a soya-bean protein isolate (isoelectric) in their diets for several weeks, showed respectively high and low titres of serum antibodies to an antigen prepared from soya-bean flour. Calves given alcohol-extracted soya-bean concentrate had no similar antibodies. 5. In addition to variations in total digesta flow, dietary nitrogen compounds were held up in the abomasum to different extents after different feeds. After a whole-milk feed or a synthetic feed prepared from casein, a slow, steady release of N occurred over at least 9 h. N hold-up after giving soya-bean-containing feeds was slight for the soya-bean flour, but extremely marked for the soya-bean protein isolate (isoelectric). The latter hold-up was followed after several hours by a rapid outflow of N from the abomasum.

Gluten-sensitive enteropathy: synthesis of antigliadin antibody in vitro

The intestinal mucosa of patients with gluten-sensitive enteropathy responds to gluten challenge in vivo with a striking increase in IgA and IgM synthesis. Whether this increase in immunoglobulin synthesis is due in some part to the production of antigliadin antibodies is examined. Using an affinity chromatography technique it has been demonstrated that in six of seven patients with gluten-sensitive enteropathy approximately half of the net increase in IgA and IgM synthesis occurring after gluten challenge can be attributed to the synthesis of antigliadin antibody. These data strengthen the hypothesis that immunological phenomena are related to the pathogenesis of glutensensitive enteropathy.

Circulating antibodies to wheat gliadin fractions in coeliac disease

Titres of circulating antibodies to wheat gliadin fractions have been determined in children with active coeliac disease using a passive haemagglutination technique. The highest titres against fractions from S.E. Sephadex chromatography of a peptic-tryptic-pancreatic digest of gliadin were obtained against Fraction 9. Titres of serum antibodies in children with active coeliac disease against a peptictryptic digest of gliadin and its ultrafiltrate were significantly higher than those in children free from gastrointestinal disorders. Titres of sera from some asymptomatic sibs of the probands were abnormally high against the peptic-tryptic gliadin digest, suggesting a minor gut abnormality in these children, despite normal duodenal mucosal histology. Haemagglutination titres of sera from patients with active coeliac disease against the protein digests and fractions evaluated seemed to be related to the toxicity of these substances in this disease.

Cellular infiltrate of jejunal biopsies in adult coeliac disease in relation to gluten withdrawal

A comparison has been made of inflammatory cell counts in the lamina propria and epithelium of jejunal biopsies in 11 patients with adult coeliac disease with those found in 12 control subjects. In the coeliac patients, there were significant increases in the numbers of total cells, plasma cells, and intraepithelial lymphocytes, but a significant reduction in lamina propria lymphocytes. Following clinical improvement on a strict gluten-free diet, significant changes in cell counts occurred, but with the exception of lymphocytes in the lamina propria, the counts were still abnormal. Analysis of five patients in whom the biopsy improved to near normal morphology and of six in whom there was no such improvement showed that significant falls in plasma cells and rises in lymphocytes in the lamina propria could occur without improvement in other morphological appearances. These results seem relevant to the problem of diagnosing coeliac disease in patients who, on gluten withdrawal, show an unequivocal clinical response, but no gross morphological improvement in the jejunal biopsy. On the basis of the observed changes in cell counts, there seems little justification in questioning the diagnosis of coeliac disease in such patients.