Robertson Parkman

Terminal Deoxynucleotidyl Transferase Activity in Human Leukemic Cells and in Normal Human Thymocytes

Peripheral leukocytes from patients with and without leukemia were assayed for presence of terminal deoxynucleotidyl transferase. Activity of this enzyme was detected in circulating leukemic cells from 11 to 13 patients with acute lymphoblastic leukemia, and in one of four with chronic myelogenous leukemia in blast crisis, but not in leukocytes from patients with other kinds of leukemia or in normal leukocytes. Its presence in a patient with chronic myelogenous leukemia in blast crisis lends biochemical support to the suggestion that some patients with chronic myelogenous leukemia undergo a lymphoblastic rather than a myeloblastic crisis. The thymocyte and leukemic-cell enzyme have the same substrate and primer preference. Normal thymocytes and leukemic cells contain two forms of terminal deoxynucleotidyl transferase that can be separated by phosphocellulose chromatography. The enzyme may provide a means for classifying leukemic cells on a biochemical basis independently of classic morphologic and clinical criteria.

Aberrations of Suppressor T Cells in Human Graft-versus-Host Disease

To determine whether imbalances in immunoregulatory T-cell subsets exist in patients with graft-versus-host disease, we analyzed T cells in three patients with acute and in six patients with chronic graft-versus-host disease after bone-marrow transplantation. The normal human peripheral-blood T-cell compartment is composed of 80 per cent TH2-and 20 per cent TH2+ T cells, and defined by reactivity with subset-specific heteroantiserums. Human suppressor cells are TH2+, whereas helper cells are TH2-. Patients with acute and chronic graft-versus-host disease had abnormalities in these populations, and their T cells frequently bore la-like antigens. Patients with acute disease lacked TH2+ cells, and the reappearance of this subset preceded the cessation of disease activity. Chronic disease, in contrast, was more heterogeneous. Suppressor cells were lacking in two patients but increased in the other four. Two of these four patients had TH2+, la+ T cells, suggesting in vivo activation of suppressor cells. Studies showing that these TH2+, la+ cells actively suppressed the in vitro immune response support this hypothesis and suggest that the immunoregulatory cells may profoundly affect the overall immune response.

Serum levels of IL-7 in bone marrow transplant recipients : relationship to clinical characteristics and lymphocyte count

IL-7 is produced by stromal cells and is the major lympho- and thymopoietic cytokine. IL-7 induces proliferation and differentiation of immature thymocytes, and protects thymocytes from apoptosis by induction of bcl-2 expression. The regulation of IL-7 production is poorly characterized, although down-regulation by transforming growth factor-β (TGF-β) has been described. We measured the serum levels of IL-7 before and after bone marrow transplant (BMT) in 32 children undergoing BMT for genetic diseases (severe combined immune deficiency (SCID) and thalassemia), aplastic anemia, and acute lymphoblastic and non-lymphoblastic leukemia (ALL and ANLL). Prior to BMT, the highest IL-7 levels were observed in patients with SCID and ALL, ie those patients with genetic or acquired lymphopenia. Patients with thalassemia and ANLL had normal levels of IL-7. Over the 8 weeks following BMT, the IL-7 levels of patients with SCID and ALL fell as the absolute lymphocyte count (ALC) increased. No detectable change in IL-7 levels was observed in the patients with thalassemia and ANLL. Levels of IL-7 were highest in the young infants with SCID compared to the age-matched controls. Together, the data demonstrate that serum levels of IL-7 in lymphopenic patients are inversely related to patient age and the absolute lymphocyte count (ALC). The inverse relationship to ALC suggests that there is either direct regulation of stromal production or more likely, binding of secreted IL-7 to lymphocytes expressing IL-7 receptors.

Complete Correction of the Wiskott-Aldrich Syndrome by Allogeneic Bone-Marrow Transplantation

Two patients with the Wiskott-Aldrich syndrome had complete donor lymphoid and hematopoietic engraftment after successful allogeneic bone-marrow transplantation. One patient had had only a temporary donor T-lymphocyte graft after a previous transplantation, for which he had been prepared with cytarabine and cyclophosphamide; the patients own T lymphocytes returned six months later. A repeat transplant, for which the patient was prepared with anti-human thymocyte serum, total-body irradiation and procarbazine, resulted in complete donor engraftment. The second patient underwent a successful transplantation after similar preparation, except that procarbazine was omitted. At 11 and five months after transplantation both had normal hematopoiesis and no evidence of graft-versus-host disease. This treatment of the Wiskott-Aldrich syndrome may be a model for the correction of other genetically determined immune and hematologic bone-marrow disorders.

Severe combined immunodeficiency and adenosine deaminase deficiency.

Because others had described a lack of the enzyme adenosine deaminase as associated with severe combined immunodeficiency, we surveyed kindreds with infants affected with such an immunodeficiency. Three infants in two families with severe combined immunodeficiency were found to have no detectable erythrocyte adenosine deaminase. Eleven family members heterozygous for adenosine deaminase deficiency were encountered among the first-degree relatives; adenosine deaminase deficiency and severe combined immunodeficiency were associated and inherited as autosomal recessive traits in both kindreds. Successful bone-marrow transplantation was carried out in two of these infants. Normal immunologic function was established in both children, but the deficiency of adenosine deaminase persisted in their erythrocytes. The enzyme deficiency did not impair the successful establishment of normal humoral and cellular immunity by transplants of bone-marrow cells from siblings who were either normal or heterozygous for adenosine deaminase deficiency.

Immunological reconstitution following bone marrow transplantation

Summary: The recipients of hematopoietic stem cell transplants are characterized by an immunodeficiency of varying severity and duration. Their immunoincompetence is due in part to: 1) a lack of sustained transfer of donor immunity, 2) a recapitulation of lymphoid ontogeny, 3) the effects of graft‐versus‐host disease and its therapy, and 4) a reduction in thymic function. Recipients can have delays in the production of naive T lymphocytes following transplantation which result in defects in the production of new antigen‐specific T lymphocytes and an inability to produce antibodies, especially to carbohydrate antigens.

Graft-versus-Host Disease after Intrauterine and Exchange Transfusions for Hemolytic Disease of the Newborn

Abstract Fatal graft-versus-host disease developed in two immunologically normal infants after intrauterine and exchange transfusions for Rh-incompatible hemolytic disease of the newborn. In both cases, the diagnosis of graft-versus-host disease was established by the clinical and pathological features of the disease and the presence of lymphoid chimerism. The origin of the lymphocytes causing the graft-versus-host disease was demonstrated by karyotype analysis to be an exchange-transfusion donor in both cases. (N Engl J Med 290:359–363, 1974)

Acute graft-versus-host disease in recipients of bone-marrow transplants from identical twin donors.

Three patients with acute leukaemia received bone-marrow from identical twin donors after pre-transplant preparation with cyclophosphamide, cytosine arabinoside, and total body irradiation. Later clinical and microscopic changes in all three patients suggested cutaneous acute graft-versus host disease. In two of the recipients thrombolytic thrombocytopenia developed during the seventh week after transplantation, and platelet half-life was reduced to 9 h in one recipient (normal 3--4 days). It is suggested that acute graft-versus-host disease in bone-marrow recipients sometimes may result from an imbalance between autoreactive lymphocytes and lymphocytes which suppress their effect and not always from genetically determined histocompatibility differences between donor and recipient.

SURFACE PROTEIN ABNORMALITIES IN LYMPHOCYTES AND PLATELETS FROM PATIENTS WITH WISKOTT-ALDRICH SYNDROME

Lymphocytes from three patients with the Wiskott-Aldrich syndrome were subjected to surface radioiodination and their 125I-labelled surface proteins were analysed by SDS-polyacrylamide gel electrophoresis and autoradiography. Autoradiographs demonstrated the absence in all three patients of an 125I-labelled protein, molecular weight of 115 000, that was present in normal individuals. In addition, one patient had an additional labelled protein, molecular weight 135 000, not found in normal individuals. The platelets from one patient were radioiodinated and the 125I-labelled membrane proteins were analysed. Glycoproteins Ia and Ib were reduced in amount and restricted in heterogeneity while glycoproteins IIb and IIIa were normal. These results suggest that the primary defect in the Wiskott-Aldrich syndrome may be abnormalities of (glyco)proteins normally present on the surface of lymphocytes and platelets.

Correction of infantile agranulocytosis (Kostmann's syndrome) by allogeneic bone marrow transplantation

Allogeneic bone marrow transplantation has been unsuccessful as therapy for genetically determined bone marrow disorders. In patients prepared for transplantation with drugs alone long-term hematopoietic engraftment is not achieved due to the overgrowth of the infused donor bone marrow cells by residual recipient hematopoietic stem cells. Utilizing a combination of total body irradiation and antihuman thymocyte serum, the successful eradication of the abnormal hematopoietic stem cells of patients with the Wiskott-Aldrich syndrome and now infantile agranulocytosis has been achieved. Following preparation with total body irradiation and antihuman thymocyte serum a 20 month old patient with infantile agranulocytosis has complete donor hematopoietic and lymphoid engraftment one year after a histocompatible allogeneic bone marrow transplant. Prior to transplantation, this patient had no circulating or bone marrow granulocytes; following transplantation he has normal numbers of circulating granulocytes with normal in vivo and in vitro function. This therapeutic result demonstrates that genetic disorders of myeloid function can be corrected by allogeneic bone marrow transplantation following preparation with total body irradiation and antihuman thymocyte serum, and suggests that infantile agranulocytosis is due to an intrinsic defect of the pluripotent hematopoietic stem cell and not to a micro-environmental defect.