Inductive pathways leading to rat tear IgA antibody responses.
OBJECTIVE
To define the inductive pathways leading to rat tear IgA antibody responses.


METHODS
Fluoresceinated dinitrophenylated bovine serum albumin was encapsulated in poly(lactide-co-glycolide) microparticles and was administered by intranasal, ocular topical, or gastrointestinal routes. Histologic methods were used to determine the microparticles' ability to access tissues associated with mucosal inductive pathways. Rats were immunized with microencapsulated antigen by intranasal or ocular topical routes. Tear IgA and serum IgG antibody concentrations were assessed by radioimmunoassay. The frequency of antibody-secreting cells in tissues, postulated to function in tear IgA induction, was measured by enzyme-linked immunospot assay.


RESULTS
Although uptake of microencapsulated antigen was greatest at the site of delivery, ocular topical administration resulted in antigen uptake in the conjunctiva and in nasal-associated lymphoid tissue. Intranasal immunization resulted in earlier and significantly higher tear IgA and serum IgG antibody responses and in higher frequencies of antibody-secreting cells in corresponding draining cervical lymph nodes and lacrimal glands than did ocular topical immunization.


CONCLUSIONS
Nasal-associated lymphoid tissue functions as a primary inductive site for tear IgA antibody responses by contributing triggered IgA-committed B cells to the lacrimal gland.
Ridley Lathers
D M
DM
Department of Immunology and Microbiology, Wayne State University, School of Medicine, Detroit, Michigan 48201, USA.
Gill
R F
RF
Montgomery
P C
PC
D000281:Administration, Intranasal; D000287:Administration, Topical; D000818:Animals; D000917:Antibody Formation; D000921:Antibody-Producing Cells / Q000276:immunology*; D001672:Biocompatible Materials; D004140:Dinitrophenols / Q000008:administration & dosage / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D018928:Immunity, Mucosal; D007071:Immunoglobulin A, Secretory / Q000096:biosynthesis*; D007074:Immunoglobulin G / Q000032:analysis; D007441:Intubation, Gastrointestinal; D019344:Lactic Acid; D008221:Lymphoid Tissue / Q000276:immunology; D008863:Microspheres; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers; D011863:Radioimmunoassay; D051381:Rats; D011916:Rats, Inbred F344; D012710:Serum Albumin, Bovine / Q000008:administration & dosage / Q000276:immunology*; D013666:Tears / Q000276:immunology*
D001672:Biocompatible Materials; D004140:Dinitrophenols; D007071:Immunoglobulin A, Secretory; D007074:Immunoglobulin G; D011108:Polymers; C034638:dinitrophenyl-bovine serum albumin; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D012710:Serum Albumin, Bovine; D019344:Lactic Acid