Genetic regulation of antibody heterogeneity: Its possible significance in human allergy

HLA-DRB1* and allergy to Parietaria: linkage and association analyses

In this study, we used the affected sibling-pairs approach to investigate the linkage of HLA (human leukocyte antigen)-DRB* with phenotypes related to allergy to Parietaria, the most common pollinosis in Mediterranean countries. The study population consisted of 51 nuclear families (235 subjects). Linkage was detected with Parietaria skin test positivity (p < (0.01), presence of IgG and IgE antibodies specific for the major allergen Par o 1 (p < 0.020 and p < 0.025, respectively), and absence of Par o 1-specific IgE (p < 0.020). High levels of Par o 1-specific IgG were associated with DRB1*1101 and/or DRB1*1104 (p < 0.0001 and p < 0.0119, respectively) in parents and probands. High levels of Par o 1-specific IgE were associated with DRB*1104 in parents (p < 0.017) and with DRB1*1101 in probands (p < 0.0146). When siblings were categorized according to high/low total IgE levels (> or =125 IU/ml and <125 IU/ml, respectively), high IgE antibody response was associated with DRB1*1104 in siblings with low total IgE (p < 0.034) and with DRB1*1101 in siblings with high total IgE (p < 0.05). These results demonstrate that HLA-DRB1*, or genes in linkage disequilibrium, contributes to susceptibility to Parietaria allergy and that total IgE levels can discriminate population subsets where different alleles (at the HLA region or at loci in linkage disequilibrium) contribute to control allergen-specific IgE synthesis.

Association of responsiveness to the major pollen allergen of Parietaria officinalis with HLA-DRB1* alleles: a multicenter study

Parietaria, a plant belonging to the family of Urticaceae, is a major source of allergenic pollen in Europe. In the context of a multinational study, we investigated whether in allergic subjects antibody response towards Par o 1, the major allergen from P. officinalis, was associated with defined HLA-DRB1* alleles. The study population consisted of 234 allergic patients: 65 from Bulgaria, 30 from Israel, 99 from Italy, and 40 from Spain. In the Italian study group, the prevalence of ST positivity to Parietaria was 77%. In Parietaria ST-positive subjects, the prevalences of IgG and IgE serum Ab towards Par o 1 were 91% and 75%, respectively. HLA-DRB1*1101 and/or 1104 were significantly positively associated with the presence of IgG Ab and with high levels of IgE Ab towards this allergen (p = 0.0007 and p = 0.012, respectively). In the Spanish study group, the positive association of DR1100 with responsiveness to Par o 1 was confirmed (p = 0.02, RR = 4, and p = 0.002, RR = 7, for IgG and IgE Ab, respectively). None of the Bulgarian patients had IgE Ab to Par o 1, whereas IgG Ab response was observed in 7 out of 65 subjects and was positively associated with DRB1*1101 and/or 1104 (p = 0.025). In the Israeli study group, responsiveness to Par o 1 was not associated with specific HLA-DRB1* alleles. In conclusion, this study shows that in allergic patients from three European populations antibody response to the major allergen from the pollen of Parietaria is associated with HLA-DRB1*1101 and/or 1104. Our data suggest that this association is stronger in subjects monosensitized to Parietaria.

Association of class II sequences encoding DR1 and DQ5 specificities with hypersensitivity to chironomid allergen Chi t I

A panel of 188 unrelated Caucasian subjects who were exposed to the larvae of Chironomus thummi (Diptera, nonbiting midges) was HLA-typed by polymerase chain reaction amplification of the second exons of the DRB, DQA1, and DQB1 genes followed by dot-blot hybridization with sequence-specific oligonucleotide probes. Type I sensitization to the allergen Chi t I and a large number of other inhalant allergens was determined by RAST and skin testing. Sixty-one individuals were found to be sensitized to Chi t I, of whom 24 were sensitive to this allergen and to no other allergens tested. Statistical analyses showed that only in the latter group were the HLA-D genes DRB1*0101, DQA1*0101, and DQB1*0501 associated with IgE-responsiveness to Chi t I. These results suggest that HLA associations with responsiveness to certain allergens may be more striking in monosensitized subjects.

Association between IgE response against Bet v I, the major allergen of Birch Pollen, and HLA-DRB alleles

The association of the human IgE response against Bet v I, the major allergen of birch pollen, and the HLA-DR and DQ phenotype was studied. Birch pollen allergic patients showed a typical case history, positive skin-prick test, and positive RAST with birch pollen extracts. They were divided into two groups. Group I (n = 37) consisted of individuals generating IgE antibodies that selectively reacted with Bet v I. Their serum IgE did not react with minor allergens from birch pollen as tested by immunoblot analysis, nor did they show a response against allergens from a panel of grass and other tree pollen or perennial allergens from animals and fungi as determined by skin-prick test. Patients belonging to group II (n = 34) possessed IgE reacting with Bet v I plus one or more additional allergens. The control group consisted of 637 healthy blood donors. Comparison of the frequencies of RFLP-defined HLA-DR and DQ alleles in patients and the control group revealed that the distribution of DRB3 alleles in group I patients differed significantly from that in the control group: A higher frequency of the DRw52a/c alleles in comparison to the control group (pcorr less than 0.02) was observed. In addition, alleles defined by nucleotide sequences coding for the amino acid sequence tyrosine-phenylalanine-histidine at positions 30-32 of the beta chain of DR molecules were found with a higher frequency in patient group I (pcorr less than 0.02), too. These alleles comprise DRw52a/c and some DRB1 alleles.(ABSTRACT TRUNCATED AT 250 WORDS)

Human immune responsiveness to Lolium perenne pollen allergen Lol p III (rye III) is associated with HLA-DR3 and DR5

A well-characterized allergen of Lolium perenne (perennial rye grass) pollen, Lol p III, has been used as a model antigen to study the genetic control of the human immune response. Associations between HLA type and IgE or IgG antibody (Ab) responsiveness to Lol p III were studied in two groups of skin-test-positive Caucasoid adults (N = 135 and 67). We found by nonparametric and parametric analyses that immune responsiveness to Lol p III was significantly associated with HLA-DR3 and DR5. No association was found between any DQ type and immune responsiveness to Lol p III. Geometric mean IgE or IgG Ab levels to Lol p III were not different between B8+, DR3+ subjects and B8-, DR3+ subjects, showing that HLA-B8 had no influence on the association. Lol p III IgG Ab data obtained on subjects after grass antigen immunotherapy showed that 100% of DR3 subjects and 100% of DR5 subjects were Ab+. A comparison of all the available protein sequences of DRB gene products showed that the first hypervariable region of DR3 and DR5 (and DRw6), and no other region, contains the sequence Glu9-Tyr-Ser-Thr-Ser13. Our observations are consistent with the possibility that immune responsiveness to the allergen Lol p III is associated with this amino acid sequence in the first hypervariable region of the DR beta 1 polypeptide chain.

Genetic and immunologic basis of atopic responses

We summarize current understanding of the genetics of human diseases and of the major histocompatibility complex related factors regulating immune responsiveness. Special factors are involved in atopic diseases as a result of the intersection between the immune system, the targets in the tracheobronchial tree and the endocrine, neurologic and genetic mechanisms affecting both the effectors and the targets. The evidence from investigations of human subjects and their families and from laboratory animals for the underlying genetic and immunologic mechanisms of asthma are reviewed. The genetic control of asthma is complex. The evidence suggests a gene or genes associated with and linked to HLA. The disease phenotype may also be regulated by genetically determined levels of IgE and the outcome of the balance between immune response and immunosuppression.

Kinetics of humoral response during the acute and the convalescent phase of human trichinosis

After a common source outbreak of trichinosis in Bitburg, FRG, 107 patients, for whom time and source of infection were precisely known, were prospectively studied for a period of eight months in order to investigate the kinetics of the humoral immune response. Antibodies were assessed by IHA, and by ELISA to quantify IgG, IgM and IgE isotypes. For four different periods of the observation time sensitivity and predictive value of tests to identify acute or convalescent trichinosis were determined. The results demonstrated characteristic kinetics of the different antibody isotypes and varying diagnostic value of the tests. Only IgG-ELISA and double-sandwich IgM-ELISA reliably identified diseased patients shortly after onset of clinical illness and showed a negative predictive value of almost 100% from seven weeks to eight months after infection. IgE antibodies and elevation of total serum IgE occurred only in about 20% of patients and showed no consistent pattern during the course of the disease. Circulating immune complexes were moderately increased four weeks after infection. They rapidly returned to normal values, after the symptoms of the acute phase had disappeared.

Potentiation of IgE production to common environmental allergens by storage house dust mite Dermatophagoides farinae

Total serum IgE and IgE antibodies against ten common antigens, including Dermatophagoides farinae (D.f.), moth, ragweed, orchard grass, cryptomeria, alternaria, aspergillus, dog dander, cat dander and tetanus toxoid, were determined using the PRIST and the Sepharose-RAST, respectively, in 100 clinically non-allergic Japanese subjects and interrelations of IgE responses to these antigens were investigated. We obtained following results. The number of positive RAST antigens, to which the subjects responded, increased in parallel to their total serum IgE levels. Among ten antigens, D.f. and moth antigens contributed a great deal to the elevation of total serum IgE level as compared with other antigens. When the relationship between IgE response to D.f. and similar responses to the other nine antigens was investigated, positive RAST responses to various antigens occurred selectively in the subjects with positive RAST for D.f., and the number of positive RAST antigens to which the subjects responded increased depending upon their D.f. specific RAST levels. Such an association was not found between IgE response to moth and the other nine antigens. These findings suggest that non-specific activation of IgE-producing B cells occurs as a result of continuing stimulation by D.f.

Demonstration of a common major gene with pleiotropic effects on immunoglobulin E levels and allergy

Atopic disease is generally recognized to be familial, although specific genetic components have yet to be identified. High levels of a unique class of immunoglobulins, immunoglobulin E (IgE), have been shown to be associated with allergies. Several investigators have reported evidence indicating a recessive regulatory locus where an individual with the homozygous recessive genotype has persistently elevated levels of IgE. Willcox and Marsh [1978] have proposed a hypothesis relating IgE production and liability to become allergic. A test of this hypothesis was carried out in the present study. Bivariate segregation analysis of IgE levels and allergy was performed on 173 nuclear families, and the results indicate that an IgE regulatory locus contributes to the familial transmission of allergy. The results are further discussed in the context of the Willcox and Marsh hypothesis.

A genetic-epidemiologic study of human immune responsiveness to allergens in an industrial population: I. Epidemiology of reported allergy and skin-test positivity

Four hundred six subjects, comprising a 10% random sample of all employees, and a sample of "self-reported" allergic employees of a light industrial plant participated in an epidemiologic study of allergy. Puncture skin testing with a wide variety of crude allergens revealed a significantly higher prevalence of IgE-mediated sensitivity in males than females (29% males and 7% females in a random group; 60% males and 30% females in a self-reported allergic group); however, reported prevalence rates for "allergy" and different allergic symptoms were generally not different between males and females. Interestingly, reported asthma was greater in skin-test-positive subjects than in skin-test-negative subjects. We also noted a decrease in skin-test positivity with increasing age in self-reported allergic subjects. This was significant in the case of several crude allergens but not in the case of positivity to at least one allergen. We also found evidence that people born in and who have been resident in "Zone I) (MD, PA, Del, NJ, or DC) for most of their lives exhibit a greater prevalence of skin-test positivity than people who were born in and have lived for much of their lives in the northeastern United States (east of the Mississippi River and to the north of South Carolina) other than in Zone I.

Correlation between lymphocyte responses and immediate hypersensitivity to purified allergens

Seventy-nine unrelated subjects were selected for high allergic sensitivity to ragweed and/or grass pollens. Sensitivities to ragweed antigens E and Ra5 and rye grass group 1 were measured by intradermal skin testing and by histamine release in vitro. Lymphocyte responses were determined by incorporation of 3H-thymidine in vitro in the presence of antigen. Skin-test and histamine-release sensitivities were significantly correlated with lymphocyte response in the case of antigen E, but not for group 1 and Ra5. In addition, lymphocyte response to antigen E was significantly correlated with total serum IgE level. Six antigen E-sensitive individuals had marked delayed, but no immediate, reactions to Ra5 and almost all showed lymphocyte responses to Ra5. We conclude that immediate sensitivity and lymphocyte responses of allergic individuals to antigen E are significantly correlated, and that lymphocyte responses and delayed reaction to an antigen without immediate sensitivity or IgG antibody are possible even in allergic subjects.