T-Cell help for the IgA response: The function of T cells from different lymphoid organs in regulating the proportions of plasma cells expressing various isotypes

Maternal Determinants of Neonatal Immune Response to Ovalbumin: Effect of Breast Feeding on Development of Anti-Ovalbumin Antibody in the Neonate

“…However, little or no IgA anti-OVA response was observed after such immunization. These obser vations are similar to studies by several other investi gators [9,10]. In the rodent, particularly rats, high lev els of maternal IgG seem to cross the neonatal gut ep ithelium in suckling neonates.…”

Con A-Propagated, Auto-Reactive T Cell Clones that Secrete Factors Promoting High IgA Responses

“…Goat antimouse p-chain antiserum was purchased from Cappel Scientific Division, Cooper Biomedical Inc., (Malvern, Pa.). Rabbit antimouse y-chain and an timouse cc-chain antisera were prepared as previously described [7] and the latter was also purchased from Miles Scientific (Naperville, III.). The specificities of these antisera were checked by immunoelectrophoresis and Ouchterlony tests and also by blocking the de velopment of PFC with purified mouse myeloma protein of the ap propriate isotype.…”

“…Heavily conjugated TNP-SRBC for use in the cultures and TNP-ox red blood cells (TNP-ORBC) for use in the IgA Fc recep tor assay, lightly conjugated TNP-horse red blood cells (TNP-HRBC) for use in the Jerne plaque assay, and TNP-conjugated keyhole limpet hemocyanin (KLH) from Calbiochem (La Jolla, Calif.) were prepared by methods previously described [7]. The TNP-KLH contained 21 TNPgroups per 100,000daltons KLH.…”

“…The clearest evidence that they may be is pro vided by the demonstration [6] that concanavalin A (Con A)-activated T cells from Peyer's patches (PP) but not from spleen or peripheral lymph nodes (PN) help B cells secrete IgA in a lipopolysaccharide (LPS)-driven system and by the Finding [7] that super natants of Con A-activated T cells from PP promote production of much higher ratios of IgA to IgM and IgG plaque-forming cells (PFC) by 2,4,6-trinitrophenyl (TNP)-primed splenic B cells in the presence of TNP-sheep red blood cells (TNP-SRBC) than do su pernatants of similarly activated T cells from spleen or PN. The demonstration that 2 PP-derived Con Apropagated T cell clones could promote expression of surface IgA (slgA) on slgA-negative B cells whereas 2 spleen-derived Con A-propagated clones could not [8,9] is supportive evidence, but not interpretable on a statistical basis.…”

“…Indeed, individual antigen-specific T cell clones from peripheral lymphoid tissues often help quite high IgA responses [12][13][14], Furthermore, when pools of anti gen-specific T cells from PP, MN and PN of SRBCprimed mice were directly compared, no important difference in their ability to help IgA responses rela tive to responses of other isotypes was found [7], Because work with Con A-activated, antigen non specific T cells provides the clearest evidence favour ing the idea that GALT is enriched in T cells that pro mote high IgA responses, we have prepared Con Apropagated T cell clones from several lymphoid or gans and compared their abilities to help IgA re sponses by TNP-primed splenic B cells. Here we pre sent the results of the comparison and describe some of the properties of four of the clones.…”