Observations on the mixed antiglobulin reaction as a test for immunoglobulin-bearing lymphocytes in normal persons and in patients with chronic lymphatic leukaemia

Robin Coombs: his life and contribution to haematology and transfusion medicine

Robin Coombs was the last survivor of the distinguished group of immunologists that included Philip Gell, John Humphrey, John Marrack, Peter Medawar and Robert White and who were responsible for the renaissance of British Immunology after the Second World War. He is best remembered for describing the antiglobulin test that bears his name. The antiglobulin test revolutionised the diagnosis of haemolytic diseases and the compatibility testing of blood for transfusion. In all, Coombs authored over 200 scientific papers. Haemagglutination reactions became widely used in the diagnosis of a range of infectious agents. Together with Philip Gell, he devised the classification of allergic reactions; these were published in the textbook "Clinical Aspects of Immunology", which he and Gell first edited in 1963 and which became the leading textbook on medical immunology. Robin Coombs was also one of the founders of the British Society for Immunology.

The mixed antiglobulin rosetting reaction (MARR) and the direct antiglobulin rosetting reaction (DARR): sensitive tests for demonstration of immunoglobulin-bearing B lymphocytes

The technology of the mixed antiglobulin rosetting (MARR) and the direct antiglobulin rosetting reaction (DARR) is reviewed. These tests have been found to be more sensitive than the standard direct immunofluorescence (DIF) method for delineation of Ig-bearing B lymphocytes and to have practical advantages over DIF. Further, with these rosette tests, an important B lymphocyte population has been identified which is Ig-negative by DIF and functionally quite different from typical DIF-positive B lymphocytes but which expresses a low density of surface membrane Ig that is detectable by the MARR and the DARR.

Immunoglobulin synthesis by neoplastic cells: models of a clonal transition from IgM to IgG synthesis

Tumour populations from two B cell neoplasms were investigated for their capacity to synthesise immunoglobulin in vitro. Neoplastic cells from a patient with chronic lymphocytic leukaemia and an IgG lambda paraproteinaemia co-expressed surface IgG lambda and IgM lambda and synthesised both IgG lambda and IgM lambda in short-term culture. In the second patient with non-Hodgkin's lymphoma, the neoplastic cells expressed surface IgM lambda but synthesised both IgM lambda and IgG lambda in vitro. The findings are discussed in terms of a model for the clonal switch from IgM to IgG synthesis.

Human regional tumour lymph nodes: alterations of micro-architecture and lymphocyte subpopulations

Axillary lymph nodes draining mammary carcinoma showed an alteration of both micro-architectue and lymphocyte subpopulations. Lymph nodes with a normal or increased T and/or B lymphocyte compartment (assessed by histology) had a low incidence of nodal tumour spread, whilst hypocellularity of the T- or B-lymphocyte-dependent areas was associated with a significant increase in metastatic invasion. Tumour-draining lymph nodes, in particular the more proximal ones, were often enlarged, spherical and tense due to an increased cellular content, predominatly B lymphocytes and their various subsets. The increased number and percentage of B lymphocytes was associated with follicular hyperplasia and prominent germinal centres. Lymph nodes with a prominent paracortex tended to have a higher ratio of T to B lymphocytes than nodes with a hypocellular paracortical area, but in many instances both the T- and B-lymphocyte-dependent areas were increased. There was no correlation between a particular axillary-node lymphocyte subpopulation pattern (assessed by surface markers) and the size, degree of necrosis, inflammatory infiltrate or histologic type of breast carcinoma, or the presence of metastatic node invasion.

Technical improvements in the mixed antiglobulin rosetting reaction with consequent demonstration of high numbers of immunoglobulin-bearing lymphocytes in viable preparations of human peripheral blood

A modification of the mixed antiglobulin rosetting reaction (MARR) to improve sensitivity as a test for immunoglobulin (Ig)-bearing human blood lymphocytes is described. A mean 5.7%, lymphocytes Ig-positive by the MARR when rosettes were formed in medium containing 0.2% bovine serum albumin (BSA), increased to 20% when rosettes were formed in 5% BSA or by incubating the lymphocytes or indicator erythocytes with Vibrio cholerae neuraminidase before rosetting. Under these various rosetting conditions the MARR is as sensitive as the direct antiglobulin rosetting reaction (DARR). Further, with the MARR, false positive rosette formation due to unusual antimembrane antibodies can be excluded during the mixed antiglobulin rosetting procedure by use of blocking controls. Substitution of F(ab)2 antiglobulin for IgG anti-gamma, anti-alpha and anti-mu did not reduce the number of lymphocytes demonstrable with the MARR, indicating that the MARR does not react with adsorbed Ig molecules on lymphocytes. Summation of the number of sheep erythrocyte (E) rosetting lymphocytes and mixed antiglobulin rosetting lymphocytes approximated 100%, yet in T-enriched preparations a maximum of 4% of lymphocytes were Ig-positive by the MARR, suggesting that null lymphocytes which have been reported to be E-negative and immunofluorescence-negative are B lymphocytes with surface Ig determinants.

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.

Blood lymphocytes surface markers and clinical findings in chronic lympoproliferative disorders

Surface receptors on peripheral blood lymphocytes have been studied in 43 cases with chronic lymphocytic leukaemia (CLL), and five cases with lymphoma and overspill. One quarter of the cases with CLL had lymphocytes with no detectable surface immunoglobulin (SIg) by direct fluorescent antibody staining. The remainder had SIgM, which was associated with SIgD in one third of the cases. 70% of the SIg negative group had extensive extramedullary involvement (EMI) compared with 35% of the SIg positive group at presentation; correspondingly more of the SIg negative group were treated. 46% of the SIg negative group were CLL patients of more than 3 years standing compared with 9% of the SIgM+D group and 32% of the SIgM group. Some explanations for this pattern are discussed.

Distribution of B, T, and O lymphocytes in blood and tissues of normal humans reflecting a kinetic model

The occurrence of the lymphocyte subpopulations TE, BFc, BC3, BFc + C3, BIg, and O-, percentage as well as absolute, was studied in lymphocyte suspensions from tonsils, abdominal lymph nodes, spleens, bone-marrow aspirates, and at the same time in venous blood. The absolute lymphocyte content (number of lymphocytes per g tissue) was highest in the abdominal lymph nodes, lower in the spleens and tonsils, and lowest in the blood. TE lymphocytes were found in the significantly highest percentage, 60%, in the blood. B lymphocytes, comprising BFc + C3 plus BIg, were present in the highest percentage in the bone marrow: 74%. Tonsils, spleens, and abdominal lymph nodes contained fewer B lymphocytes, and the blood fewest: 39%. A significant correlation was found only between the absolute numbers of T and B lymphocytes. A relationship between the absolute number of T lymphocytes and the total number of B lymphocytes as well as fractions thereof was thus demonstrated in the various tissues and in the blood and also between the blood and the tissue. O- lymphocytes were found in bone marrow, lymph nodes, and spleens, apparently as markerless precursors of other subpopulations. The main conclusion of the study is: In the lymphocytokinetic system the T lymphocytes must play a guiding role as an afferent vector, trigging the B fractions which thus constitute the efferent vector of the system.

Lymphocyte markers in newborn infants

Purified peripheral blood lymphocytes from 20 newborn infants and 12 adults have been studied for the presence of surface markers. Adults and infants did not differ in the percentage of sheep RBC-binding cells (means 58-65%) or in Ig-bearing cells measured by the mixed antiglobulin reaction (means 7.2-11.6%). However, newborn infants had a significantly lower percentage of lymphocytes binding Fc of IgG (mean 10.4%) as compared to adults (mean 17.2%). No overall correlation between plasma Ig levels and Ig-bearing lymphocytes was found but a single infant with increased plasma IgA also showed the highest level of Ig-bearing lymphocytes among all infants.

Separation of lymphocyte sub-populations using antibodies attached to staphylococcal protein A-coated surfaces

Plastic surfaces which had been coated sucessively with IgG, Staphylococal protein A (SpA) and diluted whole antiserum specific for cell membrane antigens, were used successfully to separate rabbit lymphocyte sub-populations. This method does not require the purification of SpA or antibody, and uses only small quantities of antiserum. The specificity of the cell separation method was demonstrated using various rabbit "b" locus anti-allotype sera, and the number of cells removed by the SpA-antiallotype system correlated well with the number of Ig+ve or "B" lymphocytes detected by other methods. Optimal conditions for cell attachment could readily be determined using multi-well plastic trays, and the adherent cells rapidly quantitated. Using 125I-labelled rabbit IgG (Rb IgG) or sheep IgG (Sh IgG) it was possible to quantitate the amount of IgG coupled to plastic surfaces, or binding to SpA-coated surfaces. By using 125I-labelled (As4) Rb IgG it was also possible to estimate the amount of antibody bound to SpA. The wide application of the SpA-antibody method relative to other affinity-antibody methods is discussed.

Properties of Fcgamma receptors in normal and malignant human tissues

Properties of the IgG receptors were studied by treating tissue sections or suspensions of peripheral mononuclear cells with various chemical reagents and determining changes in their ability to react with IgG-sensitized erythrocytes (EA). A heterogeneity of the Fc receptors was revealed. Iodoacetamide, 2-mercaptoethanol, sodium azide, EDTA, and a pH varying from 6.0 to 8.2 had no effect on Fc receptors in sections of normal lymphoreticular tissue and malignant tissue. Formaldehyde, low pH, and high salt concentrations affected receptor activity to various degrees. Receptors in liver sections and on monocytes were generally more resistant than receptors in spleen sections and on B lymphocytes. Receptors in malignant tissue behaved either like receptors in spleen or like receptors in liver. Although all tissues were sensitive to periodic acid, the Fc receptors in malignant tissue were always more resistant.

The lymphocyte plasma membrane: locus of control in the immune response

The lymphocyte plasma membrane is the locus of events which control the immune response. T and B lymphocytes, which mediate cellular and humoral immunity respectively, show distinctive plasma membrane morphologies and cell surface receptors. The dynamic state of these plasma components is emphasized by their lateral mobility in the fluid plane of the membrane, as well as variation in their structure or expression as the lymphocyte proliferates and differentiates in response to stimulation by antigen or mitogens. The best understood membrane glycoproteins are surface membrane immunoglobulins that serve as antigen receptors on B cells, and the histocompatability-beta2 microglobulin complex that has an immunoglobulin-like structure. Other less well defined surface structures showing modulation during the cell cycle may affect growth regulation of proliferating lymphocytes. Some of these are shared by fetal and neoplastic cells. Major theories of lymphocyte signaling are discussed, and the early events in lymphocyte activation are reviewed. While a complete model encompassing all these early events is not yet possible, the central issues can be usefully discussed in term of receptor-transducer-effector concepts derived by strong parallels from a knowledge of hormone-membrane interactions.

Combined T and B cell acute lymphoblastic leukaemia

A case of acute lymphoblastic leukaemia in a 17-year-old male is described. The patient had many distinctive features including a very high blast cell count, prominent lymphadenopathy and hepatosplenomegaly, thymic mass, and a fulminant clinical course. Immunological studies on the blast cells using a variety of techniques showed the presence of two distinct subpopulations, one having the surface characteristics of thymus-dependent (T) lymphoid cells and the other those of bursa-equivalent (B) lymphoid cells. The case therefore represents the first example of a combined T and B cell acute leukaemia.