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Biology of the human B Lymphocyte
ABSTRACTS OF ANNUAL MEETING
finding in patients with B-CLL to date has been associated with generalized disease and shortened survival. These findings indicate that TK isozyme status is a useful adjunct in predicting for the clinical behaviour of human lymphoid malignancy. PATHOGENESIS OF ANTIBODY INDUCED ACQUIRED VON WILLEBRAND’S SYNDROME
T. E. GAN,R. J. SAWEM & J. KOUTTS Departments of Medicine and Haematology. Alfred Hospital, Prahran, and Department of Medicine, Westmead Medical Centre, Wesrrnead, N.S. W .
A patient is described with clinical and laboratory evidence of von Willebrand’s syndrome in association with an IgG-kappa immunoglobulin and Bence-Jones proteinuria due to a probable lymphoproliferative disorder. He had a persistently prolonged bleeding time of greater than 20 min, Factor VIII related antigen (VIII:RAg), Factor VIII procoagulant activity (VII1:C) and Factor VIII ristocetin co-factor (V1IIR:Rcof) below 10%. Following cryoprecipitate of high purity Factor VIII concentrate infusion, he had the expected immediate rise in VIII:C, VII1:RAg and VII1R:Rcof but with a rapid decline in all 3 components within 2 h. The larger forms of V1II:RAg were preferentially removed by the reticuloendothelial system (R.E.S.) and this paralleled the fall in plasma VI1IR:Rcof level. However, no inhibitory activity could be demonstrated in vitro using the patient’s plasma or IgG. Using Protein A it was possible to demonstrate that his plasma or IgG bound Factor VIII and this complex retained its biological activity in vitro. It is postulated that the monoclonal IgG forms complexes with Factor VIII in vivo and these are rapidly removed by the R.E.S. LABORATORY CONTROL OF HEPARIN TREATMENT
K. T. GOODALL,J. TILLETT& A. S . GALLUS Department of Haematology. Flinders Medical Centre, Eedford Park, S.A. A bewildering variety of laboratory tests is potentially suitable for monitoring the anticoagulant effects of heparin treatment. We have measured 5 laboratory tests (activated partial thromboplastin time, APTT; thrombin clotting time, TCT; chromogenic substrate assay for antithrombin activity, S2238; anti-Xa activity, S2222; and heparin level by protamine sulphate neutralization) during treatment with continuous intravenous heparin infusion in 69 patients with definite or suspected venous thromboembolism. Heparin dose was adjusted to maintain the APTT result within a pre-defined ‘therapeutic range’ of 50-80 s, corresponding to a heparin level in normal platelet-rich plasma of 0.15-0.4 units/ml. The aims of this preliminary investigation are to examine the relationship of these tests to each other, and to select those tests for further study which correlate poorly with each other and are therefore likely to give dissimilar information about heparin activity. The APTT correlated well with the TCT (r = ,7534, n = 113), but relatively poorly with protamine sulphate (r = ,4772, n = 68), S2222 (r = .4048, n = 58), and S2238 (r = ,4742, n = 38) assays. The TCT correlated moderately with the protamine sulphate (r = .6131, n = 57), and S2222 (r = ,5428, n = 40) assays, and best with the S2238 antithrombin assay (r = ,7066, n = 18). Protamine sulphate neutralization correlated well with the 2 chromogenic substrate assays (S2222; r = ,7080, n = 92, S2238; r = ,7228, n = 60), and the 2 chromogenic substrate assays correlated very well with each other (r = ,7910, n = 63). P values for all correlations were highly significant; P <0.01 for that of the APTT with the 2 chromogenic substrate assays, and P < 0.001 for all other correlations. This survey suggests that, regardless of theoretical considerations, the APTT and TCT are likely to give similar information about the level of heparin effect, protamine sulphate neutralization gives somewhat dissimilar information, and there is little to choose between the two chromogenic substrate assays. We are correlating test results with clinical outcome, but do not have sufficient patients to draw conclusions at this level.
231
SOLITARY PLASMACYTOMA OF BONE AND EXTRAMEDULLARY PLASMACYTOMA: THEIR RELATIONSHIP TO MULTIPLE MYELOMA TERENCE FROST & J. VIVIAN WELLS Department of Haematology and Kolling Institute of Medical Research, Royal North Shore Hospital of
Sydney
Data on 23 cases of solitary plasmacytoma (SP) are presented, comprising 14 with solitary plasmacytoma of bone (SPB) and 9 with extra-medullary plasmacytoma (EMP). The 23 patients included 13 males and 10 females and the average age was 58 yr (range 20-8 I yr). A monoclonal immunoglobulin was found in 14 of the 22 SP patients tested (12 SPB and 2EMP). There were 5 IgG-k, 3 IgG-A, 2 IgA-I, 1 IgA-k, 2k, 8 non-secretory, and one untyped. The commonest sites of presentation for SPB were spine (43%), pelvis (21%) and femur (14%), whereas EMP most commonly presented in upper respiratory tract and mouth, and thyroid gland. Eleven of the 23 patients (9 SPB and 2 EMP) progressed to multiple myeloma (MM), with a mean interval time of 32 months between diagnosis of SP and multiple myeloma. Generally, a worse prognosis was associated with IgG-k, k, and IgG-L, than with other cases. Nonsecretory plasmacytomas are more likely to be EMP, and are less likely to progress to MM. The data suggest that monoclonal immunoglobulins are more common than previously reported in SPB. All patients received radiotherapy, and 65% received subsequent chemotherapy. Radiotherapy doses were no less than 4000 rad. SPB and EMP probably represent different diseases. EMP often has an indolent course, is commonly non-secretory, progresses occasionally to MM, and is generally treated with surgery and high dose local radiotherapy. SPB has a higher incidence of paraproteins, frequently progresses to MM, has a poorer prognosis, and may represent an early form of MM. SPB is generally treated with operative biopsy, local radiotherapy and intermittent chemotherapy. This work was supported in part by a grant from the N.H. & M.R.C. of Australia. BIOLOGY OF THE HUMAN B LYMPHOCYTE
RONALD PENNY Department of Immunology, St Vincent‘s Hospiral and the Department of Medicine, University of New South Wales, Sydney B cells are derived from precursors in the bone marrow. Migration via the blood is directed to secondary lymphoid organs such as spleen, lymph nodes and mucosa-associated lymphoid tissues. Some recirculation via efferent lymphatics and thoracic duct occurs. Differentiation to plasma cells involves progressive loss of membrane receptors (C3, Ig, Fc and Ia) with emergence of the cytoplasmic Ig synthesizing and secreting capacity of mature plasma cells. These steps are dependent in various phases to regulatory T cells, macrophages, antigen, soluble factors and MHC coded proteins. A number of other B cell activators including lectins and microbial products can reproduce in vitro these events. Corticosteroids in addition have been shown in our laboratory to enhance B cell activation significantly. During B cell maturation important genetic switches and deletions occur with respect to H and L chain expression. Great attention has been directed to the genetic events involved in coding for such mechanisms. Identification of B cells depends on demonstration of the membrane receptors, cytoplasmic immunoglobulin or more recently B cell specific antigens with monoclonal antibodies. Normal functions of B cells includes secretion of immunoglobulins (antibody, auto antibody, idiotypic antibody), interferon, osteoclast activating factor and other soluble factors influential on immune response. Disturbances of B cell function may arise from quantitative or qualitative deficiencies, malignancies (myeloma, lymphomas and leukaemias), and immunoregulatory disturbances of a primary or secondary nature that may be important in autoimmune diseases. The most dramatic recent application of B cell physiology applies in the area of hybridoma technology. As yet, only partial success has occurred in human cloning experiments.
finding in patients with B-CLL to date has been associated with generalized disease and shortened survival. These findings indicate that TK isozyme status is a useful adjunct in predicting for the clinical behaviour of human lymphoid malignancy. PATHOGENESIS OF ANTIBODY INDUCED ACQUIRED VON WILLEBRAND’S SYNDROME
T. E. GAN,R. J. SAWEM & J. KOUTTS Departments of Medicine and Haematology. Alfred Hospital, Prahran, and Department of Medicine, Westmead Medical Centre, Wesrrnead, N.S. W .
A patient is described with clinical and laboratory evidence of von Willebrand’s syndrome in association with an IgG-kappa immunoglobulin and Bence-Jones proteinuria due to a probable lymphoproliferative disorder. He had a persistently prolonged bleeding time of greater than 20 min, Factor VIII related antigen (VIII:RAg), Factor VIII procoagulant activity (VII1:C) and Factor VIII ristocetin co-factor (V1IIR:Rcof) below 10%. Following cryoprecipitate of high purity Factor VIII concentrate infusion, he had the expected immediate rise in VIII:C, VII1:RAg and VII1R:Rcof but with a rapid decline in all 3 components within 2 h. The larger forms of V1II:RAg were preferentially removed by the reticuloendothelial system (R.E.S.) and this paralleled the fall in plasma VI1IR:Rcof level. However, no inhibitory activity could be demonstrated in vitro using the patient’s plasma or IgG. Using Protein A it was possible to demonstrate that his plasma or IgG bound Factor VIII and this complex retained its biological activity in vitro. It is postulated that the monoclonal IgG forms complexes with Factor VIII in vivo and these are rapidly removed by the R.E.S. LABORATORY CONTROL OF HEPARIN TREATMENT
K. T. GOODALL,J. TILLETT& A. S . GALLUS Department of Haematology. Flinders Medical Centre, Eedford Park, S.A. A bewildering variety of laboratory tests is potentially suitable for monitoring the anticoagulant effects of heparin treatment. We have measured 5 laboratory tests (activated partial thromboplastin time, APTT; thrombin clotting time, TCT; chromogenic substrate assay for antithrombin activity, S2238; anti-Xa activity, S2222; and heparin level by protamine sulphate neutralization) during treatment with continuous intravenous heparin infusion in 69 patients with definite or suspected venous thromboembolism. Heparin dose was adjusted to maintain the APTT result within a pre-defined ‘therapeutic range’ of 50-80 s, corresponding to a heparin level in normal platelet-rich plasma of 0.15-0.4 units/ml. The aims of this preliminary investigation are to examine the relationship of these tests to each other, and to select those tests for further study which correlate poorly with each other and are therefore likely to give dissimilar information about heparin activity. The APTT correlated well with the TCT (r = ,7534, n = 113), but relatively poorly with protamine sulphate (r = ,4772, n = 68), S2222 (r = .4048, n = 58), and S2238 (r = ,4742, n = 38) assays. The TCT correlated moderately with the protamine sulphate (r = .6131, n = 57), and S2222 (r = ,5428, n = 40) assays, and best with the S2238 antithrombin assay (r = ,7066, n = 18). Protamine sulphate neutralization correlated well with the 2 chromogenic substrate assays (S2222; r = ,7080, n = 92, S2238; r = ,7228, n = 60), and the 2 chromogenic substrate assays correlated very well with each other (r = ,7910, n = 63). P values for all correlations were highly significant; P <0.01 for that of the APTT with the 2 chromogenic substrate assays, and P < 0.001 for all other correlations. This survey suggests that, regardless of theoretical considerations, the APTT and TCT are likely to give similar information about the level of heparin effect, protamine sulphate neutralization gives somewhat dissimilar information, and there is little to choose between the two chromogenic substrate assays. We are correlating test results with clinical outcome, but do not have sufficient patients to draw conclusions at this level.
231
SOLITARY PLASMACYTOMA OF BONE AND EXTRAMEDULLARY PLASMACYTOMA: THEIR RELATIONSHIP TO MULTIPLE MYELOMA TERENCE FROST & J. VIVIAN WELLS Department of Haematology and Kolling Institute of Medical Research, Royal North Shore Hospital of
Sydney
Data on 23 cases of solitary plasmacytoma (SP) are presented, comprising 14 with solitary plasmacytoma of bone (SPB) and 9 with extra-medullary plasmacytoma (EMP). The 23 patients included 13 males and 10 females and the average age was 58 yr (range 20-8 I yr). A monoclonal immunoglobulin was found in 14 of the 22 SP patients tested (12 SPB and 2EMP). There were 5 IgG-k, 3 IgG-A, 2 IgA-I, 1 IgA-k, 2k, 8 non-secretory, and one untyped. The commonest sites of presentation for SPB were spine (43%), pelvis (21%) and femur (14%), whereas EMP most commonly presented in upper respiratory tract and mouth, and thyroid gland. Eleven of the 23 patients (9 SPB and 2 EMP) progressed to multiple myeloma (MM), with a mean interval time of 32 months between diagnosis of SP and multiple myeloma. Generally, a worse prognosis was associated with IgG-k, k, and IgG-L, than with other cases. Nonsecretory plasmacytomas are more likely to be EMP, and are less likely to progress to MM. The data suggest that monoclonal immunoglobulins are more common than previously reported in SPB. All patients received radiotherapy, and 65% received subsequent chemotherapy. Radiotherapy doses were no less than 4000 rad. SPB and EMP probably represent different diseases. EMP often has an indolent course, is commonly non-secretory, progresses occasionally to MM, and is generally treated with surgery and high dose local radiotherapy. SPB has a higher incidence of paraproteins, frequently progresses to MM, has a poorer prognosis, and may represent an early form of MM. SPB is generally treated with operative biopsy, local radiotherapy and intermittent chemotherapy. This work was supported in part by a grant from the N.H. & M.R.C. of Australia. BIOLOGY OF THE HUMAN B LYMPHOCYTE
RONALD PENNY Department of Immunology, St Vincent‘s Hospiral and the Department of Medicine, University of New South Wales, Sydney B cells are derived from precursors in the bone marrow. Migration via the blood is directed to secondary lymphoid organs such as spleen, lymph nodes and mucosa-associated lymphoid tissues. Some recirculation via efferent lymphatics and thoracic duct occurs. Differentiation to plasma cells involves progressive loss of membrane receptors (C3, Ig, Fc and Ia) with emergence of the cytoplasmic Ig synthesizing and secreting capacity of mature plasma cells. These steps are dependent in various phases to regulatory T cells, macrophages, antigen, soluble factors and MHC coded proteins. A number of other B cell activators including lectins and microbial products can reproduce in vitro these events. Corticosteroids in addition have been shown in our laboratory to enhance B cell activation significantly. During B cell maturation important genetic switches and deletions occur with respect to H and L chain expression. Great attention has been directed to the genetic events involved in coding for such mechanisms. Identification of B cells depends on demonstration of the membrane receptors, cytoplasmic immunoglobulin or more recently B cell specific antigens with monoclonal antibodies. Normal functions of B cells includes secretion of immunoglobulins (antibody, auto antibody, idiotypic antibody), interferon, osteoclast activating factor and other soluble factors influential on immune response. Disturbances of B cell function may arise from quantitative or qualitative deficiencies, malignancies (myeloma, lymphomas and leukaemias), and immunoregulatory disturbances of a primary or secondary nature that may be important in autoimmune diseases. The most dramatic recent application of B cell physiology applies in the area of hybridoma technology. As yet, only partial success has occurred in human cloning experiments.