Effect of ragweed hyperimmune human gamma globulin on in vivo and in vitro parameters of ragweed sensitivity

Clinical Studies of a Purified Timothy Pollen Extract: Desensitization Therapy with a Purified Timothy Pollen Preparation Compared to a Crude Timothy Pollen Extract

“…One explanation for this finding is that provocation tests with immediate symptoms reflect type I reactions and that 'blocking' antibodies might interfere with these reactions. The finding that passively transferred rag weed hyperimmune gammaglobulin reduces nasal sensitivity on challenge to a ragweed allergen extract [27] supports this idea. Symptom scores on the other hand are based not only on the type I reaction but al so on the amplifying mechanisms contributing to the clinical picture of the allergic inflammation [21 ].…”

“…Significant correla tions have been found between the symptoms regis tered during the pollen season after DT and the levels of allergen-specific IgG antibodies [23,29] or the IgG/IgE antibody ratios obtained [32], These investi gations, however, do not conclusively define the pos sible relationship between the magnitude of rise of blocking antibody levels and the decrease in sensitivi ty attributable to DT. Although the blocking antibod ies at least under certain circumstances are protective [27] they can hardly be the only explanation for the clinical improvement obtained during DT. Neverthe less, their appearance remains the major immunologi cal parameter detectable and it seems reasonable to concentrate on those regimens or preparations which produce the maximal IgG antibody response [24], Most allergen extracts are crude, i.e.…”

Immunotherapy in Atopic Allergy – Antibody Titres and Avidities during Hyposensitization with Birch and Timothy Pollen Allergens

“…The possible role of allergen neutraliza tion by serum antibodies as an explanation for the beneficial effect of immunotherapy has recently been questioned [22]. Other possibilities may be the induction of local antibodies, functioning in immunoexclusion of the allergen molecule before it has pene trated the mucous surface [31].…”

“…Such non-reaginic antibodies may also, if of sufficiently high avidity to their antigen, suppress IgE forma tion, either by binding and eliminating anti gen from the circulation or possibly through influences of formed immunocomplexes on macrophages and/or suppressor cells [11,15,25,30], Although some investigators have found a relationship between the amount of blocking antibodies and of amel ioration of symptoms [4,23,24], others have been unable to demonstrate such an association [1,13,22].…”

Improvement of specific immunotherapy by human IgG and modified allergens

“…Indeed, Cooke's discovery of blocking antibodies was based on observations that the transfusion of blood from hyposensitized persons to untreated hay fever patients reduced symptoms in 16 out of 20 cases (13). However, later investigations have not rewarded aspirations of passive IT, In a controlled study on hay fever patients reacting to ragweed, hyperimmune (anti-ragweed) IgG or ordinary IgG were injected (102), No differences were observed regarding skin reactivity or specific or total serum IgE, whereas a marginal reduction in nasal reactivity and basophil histamine release was noted in the hyperimmune IgG-treated group. These changes were normalized within 1-2 weeks after injection (102), As mentioned above, injection of ragweed allergen extract into non-atopic subjects may lead to induction of an IgE immune response (62), Injection of hyperimmune IgG 1 week prior to until 2 weeks after injection of allergen eliminated the IgE response.…”