Structure and Biological Function of Human IgD

Abstract

The relative frequency of peripheral blood T and B cells and their biological function(s) from a group of patients with pityriasis rosea (PR) was investigated during the acute and convalescent phases of the disease using rosetting, immunofluorescent tests, and in vitro cell culturing with anti-δ and anti-μ antibodies and phytohemagglutinin (PHA). The total number of immunoglobulin (Ig) bearing cells was significantly increased, in conjunction with a slight decrease in the T cell population. Lymphocytes with surface IgD, IgM, or both Ig, accounted for the increase in the B cell population. This increase was transient, since it was only observed during the acute phase of the disease. In spite of the increase in IgD/IgM bearing B cells, the mitogenic responsiveness of B or T lymphocytes to anti-δ, anti-μ, or PHA was similar to the same patients during the convalescent phase, or to normal donors. Similary, the levels of serum IgM, IgD, IgG, IgA and IgE in PR remained constant and at a normal concentration throughout the experimental period. The significance of the transient increase in IgD/IgM bearing cells in the pathogenesis and etiology of PR and its possible impact on the immune system is discussed.

Pityriasis rosea (Gibert): abnormal distribution pattern of antigen presenting cells in situ

“…Peripheral T4ff8 ratios were not determined. There is one study in which circulating lymphocytes of PR patients were studied (20). These authors described a slight decrease in T-cells as determined by an E rosetting technique.…”

Antigen‐induced helper and suppressor T cells in normal and agammaglobulinemic chickens

“…Suppressor cells for antibody production can be induced in agammaglobulinemic (Ay) chickens by injection of B cells [l] and transfer of agammaglobulinemia to irradiated normal recipients is readily obtained with such suppressor cells [2][3][4]. However, induction of antigen-specific suppressor cells in chickens appears facilitated by the presence of bursa-"dependent" thymus cells, since suppressor activity is more significant with thymus cells from normal than from bursectomized chickens [S].…”