Stimulation of humoral antibody formation by polyanions. V. Relationship between enhancement of sheep red blood cell uptake by the spleen and adjuvant action of dextran sulfate

Abstract

The effect of a polyanion, dextran sulfate, on the uptake of 51Cr‐labeled sheep red blood cells (51Cr‐SRBC) by the spleen of mice was investigated. Enhancement of 51Cr‐SRBC uptake by the spleen could only be detected under the conditions which had previously been detected as requirement for the adjuvant action of dextran sulfate. Plaque‐forming cell (PFC) values assayed in the spleen of mice injected with dextran sulfate and graded amounts of SRBC were compared with PFC values of controls and PFC values calculated from effective antigen amounts, i. e. total radioactivity measured in the spleen of dextran sulfate‐treated animals. PFC values assayed were found to correlate with the PFC values calculated. The possible significance of increased antigen uptake by the spleen for the mechanism of adjuvant action of polyanions has been discussed.

Prolongation of Scrapie Incubation Period by an Injection of Dextran Sulphate 500 within the Month Before or After Infection

“…Some such mechanism could explain the unusual, protracted aspects of the DS500 effect. Certainly, although DS500 is traditionally considered to blockade the reticuloendothelial system, at the doses used in this work it is not cytotoxic for tissue macrophages, and while some aspects of function such as phago-lysosome fusion are interrupted (Bloksma et al, 1980), this temporary impairment by DS500 normally does not alter responses dependent on antigen presentation (Diamantstein et al, 1971). Indeed, the measurement of such immunological parameters at points throughout infection may well fail to uncover long-term interactions between cells and these 'unusual' agents.…”

“…We do not know whether peripheral nerve membranes are subject to such changes. DS500 generally increases cell pinocytosis and phagocytosis (Cohn & Parks, 1967;Ginsberg et al, 1981) and can act as both an adjuvant or a suppressor in cell-mediated immune responses (Diamantstein et al, 1971 ;McCarthy et al, 1977;.…”

Adjuvants and immune regulation by lymphoid cells

“…Carbonyl iron [57], zymosan and other glucans (Hadden et al, in [73]), and possibly polyelectrolytes in general [63] appear to act by providing a phagocytic load and macrophage replication in response to this load. Polyanions such as dextran sulfate and polyacrylic acid are strong adjuvants which also appear to act directly on macrophages [43,44,45,46], enhancing not only primary and secondary antibody responses but also the delayed hypersensitivity response to antigen given at the same site. Here something more than simple phagocytosis must be at work, perhaps a form of membrane activation analogous to that produced by hydrophobic antigens mentioned earlier.…”

Synthetic Polyacrylate Polymers as Particulate Intranasal Vaccine Delivery Systems for the Induction of Mucosal Immune Response

“…In vivo activation of B-cells in mice devoid of T-cells has also been observed [59,60]. Thus, the PAA polymers are capable of initiating an immune response in B-cells, without assistance of T-cells or APCs [60][61][62][63][64]. This ability of PAA to respond independently of T-cells has important implications for mucosal immune response as T-cell dependent IgA class switching and T-cell dependent antibody responses takes 5 to 7 days to develop [65].…”