HL-As and the immune response to gluten

Cell-mediated immunity to dietary antigens in coeliac disease

By means of the leukocyte migration inhibition test a significant depression of migration index (indicating increased immunity) was found in 10 untreated coeliac patients compared with 24 control subjects with the dietary antigens bovine serum albumin (BSA) and egg white but not with milk. The degree of immunity was similar to that obtained with gluten fraction III as antigen. Treatment with a gluten-free diet led to a decrease in immunity to egg white and BSA, but immunity to gluten fraction III was increased in the early months of treatment.

Association of HLA antigens with coeliac disease among Iraqi children

Forty children with coeliac disease were subjected to HLA-A and B antigens typing using the two-way lymphocytotoxicity technique. An increase in the frequency of HLA-B8 and B12 was found in patients as compared to the control group. Family studies conducted in 4 selected families have indicated that four out of five siblings who inherited the HLA-B8 antigen from their parents have contracted coeliac disease. In one of the families both siblings had HLA-B8 but only one of them contracted coeliac disease. It is suggested that the association of coeliac disease with HLA-antigen could be multifactorial, i.e. the disease could be attributed to the presence of more than one antigen.

Jejunal mucosal immunoglobulins and complement in untreated coeliac disease

Jejunal immunofluorescence studies have shown that there is a significantly increased incidence of extracellular IgA and complement in the basement membrane zone and lamina propria of untreated adult coeliac patients compared to coeliac patients on a gluten-free diet. IgG was also demonstrated with complement, particularly in the untreated patients. These findings, taken together with those of other studies, suggest that a local antibody-antigen reaction involving IgA and complement may be responsible for the ongoing mucosal damage in untreated coeliac disease as well as for the acute damage following gluten challenge of the treated patient. Furthermore, consequent upon this damage there may be a secondary IgG antibody response, possibly reticulin antibody, contributing to the mucosal damage.

Genetic control of immune responsiveness in man

Interest in immunogenetics originated from two streams: (a) histocompatibility in mouse and man, and (b) inheritance of specific immune responses in the guinea pig and mouse. In the mouse, there are genes associated with the major histocompatibility complex (MHC) which (i) code for antigens determining allograft responses and mixed lymphocyte reactions, (ii) control responses to certain antigens (Ir genes), and (iii) code for cell-surface antigens which elicit specific antisera (anti-Ia). In man, there is genetic control, in part X-linked, over levels of immunoglobulins and immunoglobulin classes. Evidence for MHC-linked genetic control is derived from immune responses to (i) micro-organisms, (ii) pollen antigens, (iii) food antigens, (iv) vaccines, (v) inocuous test antigens, and (vi) autoantigens. Some evidence exists for allotype-linked genetic control. Practical aspects concern influences of the MHC on susceptibility to disease, within individuals and populations.

Wheat grains: a substrate for the determination of gluten antibodies in serum of gluten-sensitive patients

A simple method of detecting gluten antibodies in serum is described. Cryostat sections of wheat grains proved to be an excellent substrate in the immunofluorescence technique. Rabbit antisera to gliadin and alpha-gliadin, and high percentage of sera from patients with gluten-induced enteropathy had antibodies that reacted with an internal structure of wheat grains. These antibodies could be absorbed with gliadin and with alpha-gliadin.

HL-A8 and the immune response to various antigens

The possession of the histocompatibility antigen HL-A8 has been correlated with serum levels of antibodies to gluten and a variety of other dietary, viral, and bacterial antigens and autoantigens. The only significant correlation with HL-A8 was of raised levels of gluten antibody. Thus it seems that HL-A8 may be associated with an enhanced immune response specifically to gluten, and not with a generally enhanced immunological responsiveness as has been suggested.

Histocompatibility antigens and myocardial infarction

The incidence of histocompatibility (HLA) antigens in 100 men with myocardial infarction was compared with the incidence in 500 healthy controls. No significant difference was found, providing no support for either a genetic or an immunological basis for myocardial infarction.

Histocompatibility antigens and dermatitis herpetiformis with special reference to jejunal abnormalities and acetylator phenotype

Sixty-one patients with dermatitis herpetiformis (DH) were studied. Of these fifty-three (87%) had the histocompatibility (HL-A) antigen HL-A8 as compared with 17% of a control population; the difference is significant. This incidence of HL-A8 among patients with DH is higher than that reported earlier for such patients and is similar to that reported for patients with adult coeliac disease. The incidence of HL-A1 was also significantly greater in the patient group, and was attributed to the increased frequency of haplotype HL-A1, 8. The frequency of HL-A8 was about equal in patients in whom DH was associated with jejunal abnormalities and in those in whom it was not. When correlated with rate of acetylation, there was no significant difference in the occurrence of various HL-A antigens.

Life cycle patterns and their genetic control: an attempt to reconcile evolutionary and mechanistic speculation

A model is proposed which implicates molecular recognition systems as the major controlling factors in life cycle expression. It is envisaged that such systems are important in immune functioning and catabolic, metabolic molecule recognition at both inter- and intra-cellular level. These recognition systems have the following characteristics: 1) Specific recognition molecules (recognisers), e.g. vertebrate antibodies, invertebrate agglutinins and plant agglutinins may recognise specific substances, e.g. antigens, catabolic and metabolic molecules. 2) The range of possible recognisable substances is very wide and variable. 3) The recognisers may themselves be recognised by other recognisers. 4) Recognisers are usually produced in large amounts only on presentation of the appropriate recognisable molecule. 5) The progressive introduction of new recognisable molecules increases the recogniser interaction, this interaction causing depression of some recogniser types (immune depression) and facilitation of other types among which may be recognisers specific for self components (e.g. auto-immunity). 6) Low juvenile viability is associated with a restricted range of available recognisers, high adult viability with increasing recogniser range and some auto-immunity/immune depression, senescence with a wide range of available recognisers and extensive auto-immunity/immune depression. Life cycle patterns and their control are discussed. It is suggested control mechanisms may include: 1) Dietary restriction and in some periods complete nutritional abstinence. 2) Specific recogniser depression, genes implicated here are the various antigens (species and polymorphic) found on cell surfaces, in the serum and in various body fluids of vertebrates, e.g. ABO, MNSs, P, Rh, Le and other blood groups, the ABO and Le secretor antigens and the HL-A antigens. In addition the immune response and mixed lymphocyte culture loci are implicated. Finally life cycle control is discussed with relation to sexual selection.

Immunogenetics of the Lennox-Gastaut syndrome: frequency of HL-A antigens and haplotypes in patients and first-degree relatives

Twenty-two patients with the Lennox-Gastaut syndrome and their families were examined for HL-A antigens by the microlymphocytotoxicity test. The antigen HL-A7 belonging to the HL-A locus showed a significantly increased frequency (p less than 0.0005) both in parents and in patients. The same antigen showed a significantly altered segregation in patients but a normal one in healthy siblings. Another antigen of the second HL-A locus, HL-A12, did not display a normal segregation in our patients, in whom it was nearly not represented.