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Biomedical subjects

R Parkman

Publications and source records attributed to R Parkman.

At least 127 records · Page 7Linked to original sources
PubMed1977

Concomitant presence of tumor-specific cytotoxic and inhibitor lymphocytes in patients with osteogenic sarcoma.

The lack of detectable tumor-specific cytotoxicity by the peripheral blood lymphocytes of patients with cancer may be due to a lack of cytotoxic lymphocytes or the presence of suppressor lymphocytes that inhibit cytotoxic cells. Unfractionated peripheral blood lymphocytes from 12 of 28 patients with osteogenic sarcoma were cytotoxic to osteogenic sarcoma cells in vitro (P less than 0,001). When the peripheral blood lymphocytes from patients whose lymphocytes were not cytotoxic underwent fractionation, a tumor-specific cytotoxic subpopulation was isolated from 11 of 13 patients (P less than 0.0001). Lymphocytes that inhibited cytotoxic activity of autologous tumor-specific cytotoxic lymphocytes were found in four of 10 patients with osteogenic sarcoma but not in six normal controls. Inhibitor lymphocytes form rosettes with sheep erythrocytes and adhere to nylon, whereas cytotoxic lymphocytes have a receptor for C3 but no surface immunoglobulin. The lack of tumor-specific lymphocytotoxicity in some patients can be due to inhibitor lymphocytes.

Cell Fractionation↗
PubMed1977

Abelson virus-transformed lymphocytes: null cells that modulate H-2.

A-MuLV-transformed lymphoid cells from Balb/c mice had the properties of null lymphocytes. They did not secrete Ig and all but one did not have detectable cell-associated Ig; one line synthesized, but did not secrete, the mu chain of IgM. The cells expressed H-2D and H-2K, but not H-21 histocompatibility antigens or theta-antigen; they had Fc receptors. Most cell lines grew to form donor cell tumors after inoculation into (Balb/c X C57B1/6)F1 mice. The tumor cells have more H-2Dd than cells passaged in vitro. Cell lines carried in vitro progressively lost H-2Dd. A line in which 5-30% of the cells were lysable by anti-H-2Dd was cloned; all eleven clones had H-2Dd (13-69% lysable) demonstrating that H-2 modulates in vitro. A clone with little H-2Dd (10-15% lysable) was tumorigenic even after treatment with anti-H-2Dd sera; at least 50% of the tumor cells were lysed by anti-H-2Dd. Thus A-MuLV-transformed lymphocytes modulate H-2 in vivo to higher levels and in vitro to lower levels.

Animals↗
PubMed1977

Bone marrow transplantation for an infant with neutrophil dysfunction.

A child with severe neutrophil dysfunction and intractable infections received bone marrow transplants from histocompatible siblings. After a first transplant preceded by cyclophosphamide (CY), antithymocyte serum (ATS) and procarbazine (PCB) preconditioning, there was no evidence for engraftment and autologous marrow function rapidly returned. Cell mediated lysis showed no evidence of patient sensitization against the marrow donor suggesting that graft rejection did not cause the transplant failure. A second transplant was performed utilizing another matched sibling donor. Total body irradiation was added to CY, ATS, and PCB for preconditioning after in vitro studies of the colony forming capacity (CFUc) of the patient's marrow cells showed normal sensitivity to radiation. Full engraftment ensued with correction of granulocyte function abnormalities. The patient eventually died of intractable pulmonary disease. Our experience with this child suggests that cyclophosphamide alone may be insufficient preparation for marrow transplantation in some patients with non-neoplastic hematologic disorders. Experimental and clinical data supporting this contention are reviewed.

Antilymphocyte Serum↗
PubMed1977

Whole antilymphocyte serum: a potent safe immunosuppressive agent for intravenous use in man.

Fifty-one renal and marrow graft recipients have been treated with whole, absorbed rabbit anti-human-lymphocyte serum. Such sera are potent nontoxic immunosuppressive agents. Preexisting sensitivity can be erased, and early rejection episodes are essentially eliminated. Prolonged treatment is necessary and safe, and it ensures a sustained depression in circulating T cells. Adaptation between kidney graft and host then occurs, so that the combination of prednisone and Imuran alone can sustain graft viability.

Animals↗
PubMed1976

Identification of a subpopulation of lymphocytes in human peripheral blood cytotoxic to autologous fibroblasts.

A naturally occurring subpopulation of human peripheral blood lymphocytes is cytotoxic to autologous and/or allogeneic fibroblasts. The autocytotoxic lymphocytes have a receptor for the third component of complement and for aggregated gamma globulin, do not form rosettes with sheep red blood cells, and are not removed by passage through nylon. The autocytotoxic subpopulation is not present in the thymus and tonsils of normal children or in the peripheral blood of individuals with X-linked agammaglobulinemia. Fibroblast absorption experiments demonstrate that the autocytotoxic cells are "sensitized" to antigens expressed on allogeneic fibroblasts in addition to the antigens expressed on autologous cells. Some normal individuals have a second subpopulation of lymphocytes that may "regulate" the autocytotoxic cells. The relevance of these observations to the murine autocytotoxic cells is discussed.

Agammaglobulinemia↗
PubMed1976

Detection of genetically determined histocompatibility antigen differences between HL-A identical and MLC nonreactive siblings.

Five patients with aplastic anemia were shown to be sensitized in vivo to the transplantation antigens of HL-A identical and MLC nonreactive sibling bone marrow transplantation donors. The sensitization in four cases were detected by antibody-dependent cell-mediated lysis (AICML) techniques, and in one case by antibody-dependent cell-mediated lysis (ADCML). In two cases the inherited nature of the sensitizing antigen was demonstrated, and in one case the inheritance of the antigen was shown by a family study to be independent of the HL-A and MLC loci. Maximal AICML was demonstrated in two cases at the time of bone marrow graft rejection. Successful transplants after immunosuppression with rabbit anti-thymocyte serum, procarbazine, and cyclophosphamide were performed in two patients, in whom sensitization was detected before transplantation.

Antibody Specificity↗
PubMed1976

Purine nucleoside metabolism in the erythrocytes of patients with adenosine deaminase deficiency and severe combined immunodeficiency.

Deficiency of erythrocytic and lymphocytic adenosine deaminase (ADA) occurs in some patients with severe combined immunodeficiency disease (SCID). SCID with ADA deficiency is inherited as an autosomal recessive trait. ADA is markedly reduced or undetectable in affected patients (homozygotes), and approximately one-half normal levels are found in individuals heterozygous for ADA deficiency. The metabolism of purine nucleosides was studied in erythrocytes from normal individuals, four ADA-deficiency patients, and two heterozygous individuals. ADA deficiency in intake erythrocytes was confirmed by a very sensitive ammonia-liberation technique. Erythrocytic ADA activity in three heterozygous individuals (0.07,0.08, and 0.14 mumolar units/ml of packed cells) was between that of the four normal controls (0.20-0.37 mumol/ml) and the ADA-deficient patients (no activity). In vitro, adenosine was incorporated principally into IMP in the heterozygous and normal individuals but into the adenosine nucleotides in the ADa-deficient patients. Coformycin (3-beta-D-ribofuranosyl-6,7,8-trihydroimidazo[4,5-4] [1,3] diazepin-8 (R)-ol), a potent inhibitor of ADA, made possible incorporation of adenosine nucleotides in the ADA-deficient patients...

Adenosine Deaminase↗
PubMed1975

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.

Adolescent↗
PubMed1975

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.

Adenosine↗
PubMed1975

Adenosine-deaminase deficiency in a child diagnosed prenatally.

Deficiency of red-blood-cell adenosine deaminase (R.B.C.-A.D.A.) has been reported in a proportion of patients with the autosomal recessive form of severe combined immunodeficiency (S.C.I.D.). In a family in which a child had died with S.C.I.D., R.B.C.-A.D.A. levels in the parents and other members of the family were compatible with a heterozygous state for A.D.A. deficiency. Cultured amniotic-fluid cells obtained from a subsequent pregnancy contained less than 1.5% of A.D.A. activity of normal amniotic cultures. The prenatal diagnosis of A.D.A. deficiency was confirmed at birth by the absence of A.D.A. ACTIVITY IN THE CHILD'S RED-BLOOD-CELLS. Clinical and laboratory findings in this child are similar to those of the sibling who had died with S.C.I.D.

Aminohydrolases↗
PubMed1975

Isolation on discontinuous gradients of bovine albumin of a subpopulation of human lymphocytes exhibiting precursor characteristics.

Purified subpopulations of lymphocytes were obtained from discontinuous bovine serum albumin (BSA) gradients and by rosetting sheep erythrocytes (E) or EAC1-3. Cells from layers 1 to 3 of the BSA gradient which failed to rosette with E were highly reactive with EAC1-3 and with anti-human IgM. Demonstrating a high spontaneous rate of DNA synthesis and primitive morphology, these cells responded to pokeweed mitogen, concanavalin A and alloantigens, but not to phytohemagglutinin or soluble antigens. Constituting from 0.5% to 3.0% of all lymphocytes from each of the tissues studied, these lymphocytes appear to represent an earlier stage in human lymphocyte development distinct from both T and B cells.

Antigens↗
PubMed1975

Selection of patients for bone marrow transplantation in severe aplastic anemia.

Despite androgens and intensive supportive care, satisfactory survival in severe aplastic anemia remains at 20% or less. Histocompatible bone marrow transplantation can restore normal hematopoiesis in approximately 40% of similarly severe individuals. Delay of transplantation for 3 wk after diagnosis allows time for proper evaluation and for many spontaneous recoveries. Further delay increases risks of fatal complications and decreases chances for successful transplantation while the incidence of spontaneous remission declines. When available, early histocompatible bone marrow transplantation may be the treatment of choice for severe aplastic anemia.

Adolescent↗
PubMed1975

Transplantation in severe combined immunodeficiency disease with hl-a identical bone marrow.

The immunologic reconstitution of 7 patients with severe combined immunodeficiency disease was attempted with bone marrow transplantation from histoidentical donors. Four patients were successfully reconstituted and discharged from the hospital. Two patients died with sepsis. One patient died from a preexisting neurologic disease. All the patients who have been successfully reconstituted have had some degree of graft-vs-host disease. A dose of 50 x 10(6) nucleated bone marrow cells per kg seems necessary for successful engraftment. The use of density gradient separation had no advantage over whole, unfractionated bone marrow.

Animals↗