The immune response of patients with ragweed hay fever treated with polymerized ragweed antigens.

This report describes the immune response of patients with ragweed hay fever treated with polymerized ragweed antigens (PRW). Their IgG antibody responses to crude ragweed extract, antigen E, antigen K, and antigen Ra3 were determined by a solid-phase radioimmunoassay. The results indicate that PRW contains an array of clinically important antigens that are available for immunologic processing and result in an immune response in patients treated with this new form of immunotherapy for ragweed hay fever.     

Mouse monoclonal IgE antibodies specific for ragweed pollen antigens

In order to obtain monoclonal IgE antibody specific for the major allergens in ragweed pollen extracts, hybridomas were constructed from spleens of mice immunized with ragweed antigen E (AgE). Two hybridomas were selected for thorough study, both secreting antibodies of the IgE class. Large quantities of IgE antibodies were isolated by affinity purification using Sepharose 4B conjugated with ragweed pollen proteins (Fraction A). Both MAbs were found to bind to a high molecular weight and heterogeneous population of proteins, but not to monomeric AgE as demonstrated by protein blot analysis. It is suspected that both MAbs react with low affinity with AgE determinants and binding could be demonstrated only with aggregated forms of AgE. Although the specific antigens with which they react are unknown, these monoclonal IgE antibodies should be useful reagents, complementing the previously obtained monoclonal anti-dinitrophenyl IgE antibody, for studying various aspects of the mouse and human IgE antibody systems.     

Preparation of carbon-14-labelled whole short ragweed pollen antigens.

A new method of labelling short ragweed pollen antigens with carbon-14 is described. The known ragweed antigens AgE, Ra3, Ra5 and several other antigens are radiolabelled. These components are biologically active, have a high specific radioactivity and a long half-life.     

Comparison of immune reactivity to polyvalent monomeric and polymeric ragweed antigens

The proteins of an aqueous extract of ragweed pollen (RW) were precipitated at 90% saturation with (NH4)2SO4, solubilized, and sieved through Sephadex G-15. The excluded fraction, termed the monomeric form (MRW), was cross-linked with glutaraldehyde to form polymerized ragweed (PRW). As compared with MRW, PRW is more immunogenic in rabbits in the production of antibody against RW antigen E (AgE). MRW and PRW resulted in equal peak reaginic responses in rabbits but the duration of reagin production was longer after immunization with MRW than with PRW. Both MRW and PRW have exposed antigenic determinants of AgE but PRW had approximately 1/3 the number as shown by neutralization of human antibody against RW AgE. PRW had 100-to 1,000-fold less human cutaneous reactivity than MRW. PRW may be a more easily effective therapeutic agent for human RW immunotherapy than currently used aqueous extracts and may be more readily obtainable than polymerized AgE.     

The relationship between HL-A antigens and lymphocyte response in ragweed allergy.

The association between clinical ragweed hypersensitivity and HL-A haplotype inheritance has been confirmed. The lymphocyte response to phytohemagglutinin was greater in symptomatic individuals than in their asymptomatic relatives.     

The characterization of some of the antigens and allergens in ragweed pollen.

Ragweed extract (RW) and antigens E, K, BPA-R and Ra3 were characterized by electrophoresis on starch and polyacrylamide gels. RW extract and antigen E were also subjected to crossed immunoelectrophoresis. All the antigens contained isomers and contaminating proteins. RW separated by starch gel electrophoresis was skin tested and allergens unrelated to antigens E, BPA-R, Ra3 and K were found.     

Studies on the immunological relationship of ragweed pollen antigens E and Ra.3

This study compares the allergenic and antigenic activities of ragweed pollen antigens Ra.3 and E using the human leukocyte histamine release assay. Leukocytes from 23 antigen E-sensitive patients were challenged separately with varying concentrations of Ra.3 and E. Six were unresponsive to Ra.3, although the same cells released 60 to 100 per cent histamine on challenge with antigen E. The leukocytes of 16 patients gave maximal release of 50 to 100 per cent with Ra.3. Leukocyte sensitivity to Ra.3 relative to E ranged from 0.1 to 10⁴ and demonstrated little or no allergenic cross-reaction between the 2 antigens. Skin tests on an additional 19 patients confirmed this pattern. Leukocytes were challenged separately with mixtures of each allergen and dilutions of human antisera to antigen E (α-AgE) and water-soluble ragweed (α-AgWSR). Whereas α-AgWSR and α-AgE were equally inhibitory to E-induced histamine release, only AgWSR effectively inhibited Ra.3-induced release. Rabbit antiserum to Ra.3 and AgE in most patients inhibited the homologous allergen and demonstrated little or no cross-reactivity. In 2 patients, however, anti-AgE inhibited Ra.3-mediated histamine release while the homologous antiserum was inactive. We conclude that antigens Ra.3 and E are antigenically and allergenically distinct.     

A multi-institutional trial of polymerized whole ragweed for immunotherapy of ragweed allergy

Eighty ragweed-sensitive patients in four cities were recruited to study the safety and efficacy of partially purified, polymerized whole ragweed (PRW) as an improved form of immunotherapy. Groups of 20 patients in Chicago, Boston, Memphis, and St. Louis had blood drawn for immunologic studies before and after the 1978 and 1979 ragweed seasons and completed detailed daily symptom score sheets each day of the 1978 and 1979 ragweed pollen seasons. Beginning in March, 1979, all patients except one received 15 weekly injections of PRW totaling 50,000 protein nitrogen units (PNU) and containing about 500 μg ragweed AgE. One patient received 25,000 PNU. Symptom score indices of the posttreatment 1979 season were compared with those from the pretreatment 1978 season and also with the scores of similar groups of ragweed-sensitive patients in each city treated only with medication for symptomatic relief during the 1979 season. Local reactions to polymerized ragweed immunotherapy were minimal. No abnormalities in complete blood count, erythrocyte sedimentation rate, chest x-ray film, urinalysis, or rheumatoid factor occurred in the immunotherapy-treated groups. Total serum antibody binding of ragweed AgE increased 12-fold following immunotherapy. When compared either with their 1978 untreated group scores or when compared with scores from the untreated group in each city in 1979 (control group), the symptom score indices of the immunotherapy-treated groups in 1979 were significantly improved. PRW is efficacious in the treatment of ragweed hay fever and can be administered more safely and in higher doses with fewer injections than conventional extracts. It represents an improved form of immunotherapy.     

Effect of immunotherapy on immunoglobulin E and immunoglobulin G antibodies to ragweed antigens: a six-year prospective study

The effect of immunotherapy with aqueous short ragweed (SRW) extract on IgE and IgG antibodies was tested over a 6 yr period in 47 adults with ragweed hay fever. Sera were collected each year in July and October from 1973 through 1979. In May 1976, 23 patients began immunotherapy with a lyophilized standardized SRW extract. From 1976 through 1979, treated patients received an average total dose of 4.8 × 10³ protein nitrogen units (1039 μg of AgE). IgE antibodies to SRW and ragweed AgE were measured by the radioallergosorbent test (RAST) in antigen excess using allergens bound to Sepharose. Blocking antibodies primarily of the IgG class were measured by RAST interference. In response to inhalation of ragweed pollen, untreated patients showed seasonal rises (July to October) and postseasonal falls (October to July) of IgE antibodies during the entire study period. IgE antibody levels in the untreated patients decreased with time and from 1974 to 1979 fell 41% (p < 0.003) for an average halftime of 6.2 yr. Before immunotherapy, treated patients also showed seasonal rises and postseasonal falls. Treatment with SRW extract in 1976 produced an abrupt increase in IgE and IgG antibodies and a clear-cut suppression of seasonal rises of IgE antibodies without an effect on postseasonal falls through 1978. From 1974 to 1979, IgE antibodies to AgE and SRW decreased more in the immunized group than in the control group, and by 1979 these levels showed a mean fall of 73%. Blocking antibodies increased in the treated patients and reached maximal levels by July 1978. In 1978 and 1979, the levels of IgG blocking antibodies to AgE were inversely related to the IgE antibody levels to AgE. These results indicate that adults with ragweed hay fever show regular seasonal and postseasonal changes in IgE antibodies and that IgE antibodies spontaneously decrease with time. Immunotherapy magnifies these decreases by suppression of the seasonal rises, but it does not affect the postseasonal falls.     

Modifications of the Wright Dust Feed Mechanism permitting stable dispersion of native ragweed pollen.

Conventional methods have not provided aerosols of suitable constancy. The Wright Dust Feed Mechanism was adapted to provide tractable pollen dispersion.     

A double-blind, placebo-controlled trial of polymerized whole ragweed for immunotherapy of ragweed allergy

Immunotherapy with polymerized ragweed (PRW) has been demonstrated to be safe and effective when compared with monomeric ragweed or untreated controls. To further establish the efficacy of PRW, a trial was conducted comparing PRW, placebo, and no treatment in ragweed-sensitive individuals. In a double-blind manner, 21 patients were treated before the 1981 ragweed season with 15 weekly injections of PRW totaling about 50,000 PNU and 1200 μg antigen E, while 19 patients were treated with 15 weekly injections of a caramelized glucose and histamine placebo. An additional control group received no injections. Blood was drawn for IgE against ragweed antigen E (IgE-a-AgE) and for blocking antibody against AgE before treatment, after treatment (before season), and after season. In the untreated patients, blood was drawn before season and after season. Daily symptom score sheets were completed by patients each day of the ragweed season. Blocking antibody rose more than 40-fold with treatment (p = 0.0001) in the PRW group but was unchanged in the placebo group with treatment. IgE-a-AgE rose with PRW therapy. Clinical efficacy of PRW was again confirmed in this study. Symptom score mean in the PRW group was statistically lower than the mean in the placebo group (p = 0.022) and in the untreated group (p = 0.018). There were no systemic reactions and only minor local reactions during treatment. In summary, PRW is an improved form of immunotherapy.