Induction of IgE-Secreting Cells in the Lymphatic Drainage of the Lungs of Rats following Passive Antigen Inhalation

Abstract

Repeated challenge of high-IgE-responder BN rats with an antigen aerosol in the absence of adjuvant, elicited both specific IgE and IgG responses in serum. Employing the recently developed ELISA plaque assay to detect individual IgE and IgG secreting cells, the lymph nodes draining the lower respiratory tract were pinpointed as the site for initiation of this response, and the sole location of specific IgE-secreting cells. Subsequent analysis of the tissue distribution of total IgE-secreting cells revealed that ≥50% were located in the lymph nodes draining the upper and lower respiratory tracts.

Intranasal Immunization with a Colloid-Formulated Bacterial Extract Induces an Acute Inflammatory Response in the Lungs and Elicits Specific Immune Responses

“…A rise in the level of specific antibacterial IgE that could explain the increase in total IgE production by day 54 could not be demonstrated, although that may be due to the fact that a low IgE/IgG ratio in serum could result in low sensitivity of the ELISA. An initial increase in the total serum IgE concentration would be consistent with the described Th2-like initial response to inhaled antigens (29,30,43,60,61). However, the later decrease in the IgE level may suggest that the BEs exert an immunomodulatory effect on IgE production.…”

A Contiguous Network of Dendritic Antigen-Presenting Cells within the Respiratory Epithelium

“…Notably it is now well established that DC populations constantly traffic from the epidermis and the gut wall to regional lymph nodes, carrying antigen(s) picked up during their sojourns within their respective epithelia [15][16][17], and accordingly it seems likely that a similar mecha nism operates to shunt inhaled allergen from the upper respiratory epithelium to the draining lymph nodes. In experimental systems, these regional lym phoid structures represent the major sites of IgE-regulatory T cell activation and IgE production in re sponse to inhaled antigens [18,19], and consequently factor(s) which influence the rate of DC influx from the adjacent respiratory epithelium or their func tion^) may be of major importance in relation to ex pression of the allergic phenotype.…”

Reactivity of Lymphoid Cells Isolated from the Tracheobroncheal Lymph Nodes of Two Guinea-Pig Strains with High or Low Susceptibility to Respiratory Anaphylaxis

“…In mice, rats and hu mans, the synthesis of this antibody is regulated by an intricate network of lymphocytes [1,14,15]. In mice and rats, it has been shown that the main site of regu lation and synthesis of IgE is located in the lymph nodes draining the mucosal surfaces of the airways [2,3,16]. Holt and Sedgwick [17] and Jarrett [18] pro posed the existence of a regulatory mechanism in the local immune system of the airways, believed to con trol the level of IgE in the normal non-allergic indi vidual, through the action of an IgE isotype-specific suppressor cell system.…”

“…In sensitized rats, which are subjected to antigen inhala tion, IgE is synthesized mainly in the lymph nodes draining the respiratory mucosa [2,3]. This synthesis may be regulated by T lymphocytes [2,4], Two guinea-pig strains, designated IMM/S and IMM/R, inbred for high or low susceptibility, respectively, to respiratory anaphylaxis upon inhalation with an aer osol containing ovalbumin (OA), provide a very suit able experimental model for studies of allergic asthma [5][6][7][8][9][10], By analogy, the low responder strain, IMM/R, may be considered to represent a non-allergic and the high responder strain, IMM/S, an allergic individual.…”