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A J Munro

Publications and source records attributed to A J Munro.

12 recordsLinked to original sources
PubMed1979

Non-specific immunosuppressive effects of mouse spleen extracts in vitro.

Cell-free extracts were prepared from the spleens of keyhole limpet haemocyanin (KLH)-primed, ovalbumin (OVA)-primed or unprimed mice, and were shown to suppress non-specifically the secondary antibody response to TNP1000KLH in vitro. Non-specific activity was retained on storage in liquid nitrogen and was not removed by dialysis. These findings are in contrast to those reported elsewhere where it was found that cell-free extracts from the spleens of KLH-primed mice specifically suppressed the IgG response to TNP1000KLH; this discrepancy may well lie in the initial immunological status of the mice used. Nevertheless it is concluded that proper account should be taken of non-specific suppressive effects when studying the activity of cell-free extracts in vitro.

Animals↗
PubMed1978

The detection of alloantibodies to subpopulations of human lymphocytes: an adaptation of the indirect anti-immunoglobulin rosetting reaction (IARR).

An indirect anti-immunoglobulin rosetting reaction (IARR) can be successfully used to detect alloantibodies to human lymphocytes. In this paper we describe an adaptation of the IARR which allows detection of alloantibodies to human lymphocyte subpopulations. Fluorescein labelled sheep red cells, as a T cell marker, are incorporated into the rosetting reactions and by looking for rosettes with two indicator cell types, sheep and ox, one can determine if the alloantibodies are reacting with T cells or non-T cells. This type of assay is more sensitive than a standard cytotoxic test and can detect non-cytotoxic antibodies. The results show that this rosetting assay with two types of indicator cell can be useful in the study of pregnancy anisera, particularly those that are thought to contain reactivity directed solely against non-T cells. These antisera probably recognise the human DR antigens which are thought to be equivalent to the rodent Ia antigens.

Animals↗
PubMed1977

An indirect anti-immunoglobulin rosetting reaction to detect alloantibodies to human lymphocytes.

A test is reported which detects alloantibody, absorbed onto the surface of human lymphocytes from multiparous antisera, by means of a red cell rosette assay. The red cells, trypsinised ox, are coupled with anti-immunoglobulin using chromic chloride. The antiglobulin used is rabbit anti-human IgG (Fc), chosen to avoid reaction with the surface immunoglobulin naturally present on human B lymphocytes. The reaction is termed the Indirect Anti-immunoglobulin Rosetting Reaction (IARR). The IARR is shown to be specific in the following ways: anti-immunoglobulin coupled ox cells do not react with normal human lymphocytes nor with lymphocytes treated with non-reactive serum. Red cells coupled with normal rabbit IgG do not react with normal or alloantibody coated lymphocytes. Multiparous sera (reactive with other individuals) do not react with cells of the serum donor in the IARR. Finally, the coupled red cells do not usually react with lymphocytes which have absorbed immune complexes onto their Fc receptors. The IARR is shown to be more sensitive than a standard cytotoxic test for detection of alloantibody. Several possible applications of the IARR are discussed.

Isoantibodies↗
PubMed1977

Suppressor T cell product, which depresses the passive transfer of contact sensitivity, shares epitope(s) with the major histocompatibility complex.

Specific suppressor T cell product appears in the supernatant of cultures of lymph node cells of mice injected with picryl sulphonic acid and then painted with picryl chloride. It is detected by its ability to depress the passive transfer of contact sensitivity by immune cells incubated in it. This communication shows that the product can be absorbed by antisera prepared against the major histocompatibility locus but not by antisera prepared against mouse immunoglobulin.

Animals↗
PubMed1976

Cooperation across the histocompatibility barrier: H2d T cells primed to antigen in an H-2d environment can cooperate with H-2k B cells.

H-2d spleen cells derived from either tetraparental or semiallogeneic radiation bone marrow chimeras can be primed to antigen within H-2d recipients to generate helper T cells capable of cooperating in a secondary response with equal efficiency with H-2d or H-2k B cells. Thus it would seem that the cooperative act between T and B cells does not require that the T cell interacts with its target B cells by either cell interaction genes or via an altered self mechanism involving both antigen and the target B-cell I-region products. This does not preclude a requirement for associative recognition or altered self in the interaction of helper T cells with accessory cells.

Animals↗
PubMed1976

Antigen-specific T-cell factor in cell cooperation and genetic control of the immune response.

Cell interactions between thymus-derived (T) and bone marrow-derived (B) lymphocytes in the antibody response appear to involve soluble T-cell mediators known as 'factors.' This paper describes the properties of a T-cell factor that has specificity for the inducing antigen, a synthetic polypeptide (T, G)-A--L, and is able to replace T cells in the thymus-dependent antibody response to (T, G)-A--L. Besides antigen specificity, the main features of the molecule are that it is nonimmunoglobulin; it has a molecular weight of about 50,000; and it is a product of the I-A subregion of the H-2 complex (the mouse major histocompatibility complex). These properties suggest that the factor is closely related to the T-cell receptor, which may, by inference, also be a product of the H-2 complex. The factor cooperates well with allogeneic B cells. It can also be absorbed by bone marrow cells and B cells. Studies on the genetic control of the immune response to (T, G)-A--L using the T-cell factor indicate that two immune response genes in the H-2 complex are involved in genetic control, one expressed in T cells and the other in B cells. This two gene hypothesis has been confirmed by showing that an F1 between two low responders to (T, G)-A--L can be a high responder.

Animals↗