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Biomedical subjects

D L Longo

Publications and source records attributed to D L Longo.

At least 307 records · Page 17Linked to original sources
PubMed1990

Lymphocytic lymphoma of intermediate differentiation: morphologic, immunophenotypic, and prognostic factors.

Diffuse intermediately differentiated lymphocytic lymphoma (IDL) is a rare (approximately 2.5%) histologic subtype of malignant lymphoma. We have reviewed the morphologic, immunophenotypic, and clinical features of this disease in 23 patients treated at the National Cancer Institute in the 25-year period between 1963 and 1988. These tumors are uniformly of B-cell origin, but most of them express the T-cell antigen CD5; lambda light chain was expressed nearly twice as frequently as kappa. Median age at diagnosis was 58 years; all patients presented with stage III or IV disease, and the natural history of disease in these patients was heterogeneous. Median survival of patients was more than 5 years, but those with liver involvement documented by biopsy had a significantly shorter survival. No other prognostic factor or combination of prognostic factors significantly affected survival in this small series; however, patients with high expression of the proliferation-associated nuclear antigen Ki-67, absence of cell-surface antigens CD9 and CD10, and blastic morphology appeared to have poorer survival. Treatment was heterogeneous, but patients who achieved a complete response to combination chemotherapy survived longer than patients who failed to achieve a complete response. Only two patients had complete responses lasting longer than 2 years. Unlike patients with follicular lymphoma, those with relapsed IDL did not undergo histologic progression of the disease to an aggressive lymphoma. However, as with patients with follicular lymphoma, it was possible to observe patients with IDL without therapy for periods up to 5 years. Although a significant minority of patients may have very aggressive disease, it appears that, in most patients, IDL behaves similarly to other lymphomas with indolent histology, and thus, an optimal therapeutic approach has not yet been defined.

Adult↗
PubMed1990

Expression and role of p75 interleukin 2 receptor on human monocytes.

We investigated the expression of IL-2R subunits in human monocytes using the TU27 mAb, which recognizes the p75 chain, and anti-Tac mAb, which recognizes the p55 moiety of the IL-2R. We found that p75 but not p55 is constitutively expressed in more than 90% of fresh human monocytes. Antibody to p75, but not to p55, inhibited the activation of monocytes to a cytotoxic stage induced by IL-2 but did not block IFN-gamma-induced cytotoxicity. Our data demonstrate that the p75 chain is expressed on human monocytes and is involved in the activation of monocytes by IL-2.

Antibodies, Monoclonal↗
PubMed1990

Recombinant human granulocyte-macrophage colony-stimulating factor in patients with advanced malignancy: a phase Ib trial.

We evaluated the toxic, hematopoietic, and immunomodulatory effects of recombinant human granulocyte-macrophage colony-stimulating factor (rHuGM-CSF). The rHuGM-CSF was administered at doses up to 50 micrograms/kg by daily 2-hour intravenous infusions to 11 patients with advanced malignancy. It induced dose-related increases in cells of the myeloid series, but it had no significant effect on reticulocyte or platelet counts. Bone marrow cellularity increased with higher doses of rHuGM-CSF, but there was a dose-related decrease in the number of colony-forming units--granulocyte-monocyte--and colony-forming units--granulocyte-erythrocyte-monocyte-megakaryocyte--per 10(5) bone marrow cells. The rHuGM-CSF caused transient increased expression of CD11b and CD16 on granulocytes but increased expression of HLA-DR and decreased expression of the high-affinity Fc receptor on monocytes and no change in monocyte production of H2O2. Thus, rHuGM-CSF has potent effects on granulocyte, eosinophil, and monocyte numbers in the peripheral blood and bone marrow. In addition, it enhances the expression of monocyte and granulocyte activation-associated surface markers.

Antigens, Differentiation↗
PubMed1990

A role for cytokines in antigen presentation: IL-1 and IL-4 induce accessory functions of antigen-presenting cells.

Fixation of APC with 1-ethyl-3-(3-dimethylamino-propyl)carbodiimide (ECDI) eliminates their ability to stimulate proliferation of alloreactive T cells or the D10 T cell clone, although a partial response, IL-4 production, was measured. However, if APC were activated before fixation, they could be ECDI-fixed and retain the ability to induce T cell proliferation. IL-1, IL-4 or LPS were capable of activating APC in this way, whereas IFN-gamma was not. This activation step occurred in 6 h, required protein synthesis, and was distinct from increases in Ia or IL-1. This suggests resting APC lack structures that are essential for inducing T cell proliferation.

Animals↗
PubMed1990

Phorbol ester-induced, cell-cycle-specific, growth inhibition of human B-lymphoma cell lines.

The activation, growth, and differentiation of three B-cell- and one non-B-cell-derived human lymphoma cell lines were examined after treatment with protein kinase C-activating phorbol esters. Treatment with these agents resulted in early activation events similar to those observed in normal B cells. However, in contrast to their growth-promoting effect on normal human B lymphocytes, exposure to these phorbol esters induced profound growth inhibition of the three B-cell-derived lymphoma lines. Maximal inhibition was achieved within 24 hours of culture initiation and could be reversed if the phorbol ester was removed after 12, but not 20, hours in culture. Cell-cycle analysis of phorbol ester-treated lymphoma cells revealed a G1/S block in one line, whereas cells from the other two lines accumulated in G2/M. These data demonstrate that protein kinase C-binding phorbol esters can interrupt the cell cycle in two places in actively dividing human B-lymphoma cells. These findings may prove valuable with regard to potential therapy of human malignant lymphomas.

Antigens, Differentiation, B-Lymphocyte↗
PubMed1990

T cell tumor cure by T cell receptor-mediated activation requires the development of CD8-dependent host immunity.

The participation of the host in eliminating Ag-specific T hybridoma cells after their in vivo activation was studied. In our model system, treatment of the cytochrome c-specific T cell hybridoma 2B4.11 in vitro with Ag in the context of histocompatible APC results in cellular activation, as shown by IL-2 release and growth inhibition. In vivo treatment with Ag results in tumor cell elimination as a result both of a direct inhibitory effect of cytochrome c that is mediated through the 2B4.11 TCR and to the induction of host immunity. In vivo lymphocyte-depletion studies showed that CD8-bearing cells were critical to the successful elimination of tumor cells mediated by Ag, whereas depletion of CD4-bearing cells had only minor effects on the outcome. Cytotoxic cells from mice cured by Ag treatment lysed only 2B4.11 among a panel of related tumors, although in vivo cross-protection studies showed that 2B4.11-immune mice were also resistant to the growth of BW5147 and C10.9. Because spleen cells from 2B4.11 immune mice did not recognize 2B4.11 or other related tumors in proliferation assays, we concluded that a participant(s) with memory and specificity, not assayed in vitro, was also involved in the mediation of the immune effects observed. For therapies based on the use of less selective agents, i.e. mAb that share the activating properties of Ag but can react with T cell neoplasms of unknown specificity, it would appear that a relatively intact immune system is required for maximal success.

Animals↗
PubMed1990

CD8 is required during positive selection of CD4-/CD8+ T cells.

Interactions between self-MHC molecules and T cells are necessary for the proper development of mature T cells, in part due to an absolute requirement for self-MHC-TCR interactions. Recently, we showed that CD4-mediated interactions also participate in shaping the T cell repertoire during thymic maturation. We now examine the possible role of the CD8 molecule during in vivo T cell development. Our results demonstrate that perinatal thymi treated with intact anti-CD8 mAb fail to generate CD8 single-positive T cells, while the generation of the other main phenotypes remains unchanged. Most importantly, the use of F(ab')2 anti-CD8 mAb fragments gave identical results, i.e., lack of generation of CD4-/CD8+ cells, with no effect on the generation of CD4+/CD8+. Furthermore, selective blocking of one CD8 allele with F(ab')2 mAbs in F1 mice expressing both CD8 alleles did not interfere with the development of CD4-/CD8+ cells, demonstrating that the absence of CD8+ T cells in homozygous mice is not due to depletion, but rather is caused by a lack of positive selection. This is most likely attributable to a deficient CD8-MHC class I interaction. Our findings strongly advocate that CD8 molecules are vital to the selection process that leads to the development of mature single-positive CD8 T cells.

Animals↗
PubMed1990

Immunomodulatory properties and toxicity of interleukin 2 in patients with cancer.

We performed a phase Ia/Ib study of interleukin 2 (IL2) in patients with cancer. Single doses of IL2 from 10(3) units/m2 to 10(7) units/m2 were well tolerated but failed to induce significant immunological changes. Chronic IL2 treatment for 5 days out of 7 for 3 weeks was well tolerated at doses below 10(7) units/m2 and was accompanied by significant immunological changes. Following chronic treatment with intramuscular injections of IL2 at 1 x 10(6) units/m2, we observed augmentation of peripheral blood natural killer activity and induction of peripheral blood LAK activity. Induction of LAK activity was most evident when IL2 was included in the cytotoxicity assay. There was a marked increase in the number of peripheral blood mononuclear cells bearing the Leu-19 marker in association with the observed increases in natural killer and LAK activity. A small percentage of Leu-19+ cells coexpressed CD3. There was heterogeneous expression of the low affinity Fc receptor (CD16). In vivo induced Leu-19+ cells could be divided into two populations, dim and bright, based on the intensity of fluorescent staining with antibodies to Leu-19. The majority of Leu-19 bright cells were CD16- while the majority of Leu-19 dim cells were CD16+. In addition, the intensity of CD16 staining was higher for Leu-19 dim cells than for Leu-19 bright cells. Increases in the amounts of CD38 and CD8 antigens were also observed. Significant increases in serum levels of the soluble IL2 receptor were observed during treatment. One partial remission was noted in a woman with non-Hodgkin's lymphoma.

Cell Line↗
PubMed1990

Surface light chain phenotype in indolent lymphomas: lack of prognostic significance.

The indolent follicular and diffuse lymphomas are neoplasms of B-cell origin. In several other B-cell neoplastic disorders, including multiple myeloma, hairy cell leukemia, and chronic lymphocytic leukemia, the light chain isotype of the surface immunoglobulin has been reported to have prognostic significance. Patients with tumors expressing lambda light chains usually fare more poorly than those with kappa light chain-bearing tumours. We analyzed the clinical data and immunologic phenotype of 101 patients with indolent lymphoma. Eighty-nine of the 101 patients demonstrated surface immunoglobulin of only one light chain type (kappa-47, lambda-42). Patients in both groups were matched for known prognostic factors. There were no significant differences in disease-free survival or overall survival between the two groups or within histologic subtypes. These results indicate that the immunologic light chain phenotype in indolent lymphoma, unlike other B-cell neoplasms, is not a prognostic indicator of survival.

Humans↗
PubMed1990

Biological response modifiers in the management of patients with breast cancer.

Despite impressive progress in understanding the biology of breast cancer, mechanisms of host defense, and the pathophysiology of the metastatic process, this burgeoning fact bank has made little impact on the management of patients with breast cancer. There are many interesting ideas for improved diagnosis and therapy in various stages of development, but few have actually translated into improved survival of patients with breast cancer. Potentially useful biological agents include cytokines, monoclonal antibodies, immunotoxins, vaccines, and adoptive cellular therapies. Therapies targetting growth factor receptors and the cellular machinery required for metastasis may become useful, especially when used in combination with other cytotoxic agents. Colony-stimulating factors may allow a test of the hypothesis that augmented dose-intensity of cytotoxic chemotherapy will cure more patients. Though we are not yet sure precisely how to use all of these new tools, there can be little doubt that their application will make a significant impact on the management of patients with breast cancer and other malignancies in the next decade.

Biological Products↗
PubMed1990

Lymphocytic lymphoma of intermediate differentiation. Morphologic and immunophenotypic spectrum and clinical correlations.

All cases of lymphocytic lymphoma of intermediate differentiation (IDL) referred to the National Cancer Institute were reviewed in order to define the histopathologic spectrum of the disease and to investigate morphologic and immunophenotypic features with potential prognostic relevance. Thirty-three cases were classified as IDL according to histologic criteria. Immunophenotypic analysis was performed in 27 cases, and clinical records were available for 22 patients. The median age was 58 years, and the male-to-female ratio, 3.4:1. All patients presented with stage III or IV disease, and five had extranodal presentations. Median survival was 56.3 months, with only three patients having a prolonged relapse-free survival (greater than 2 years). Morphologically, 14 cases were diffuse or only vaguely nodular; 18 cases showed a mantle zone pattern with naked germinal centers. There was a trend toward prolonged median survival for patients with the mantle zone (77.4 months, p = 0.098). The neoplastic population was composed of irregular or cleaved small lymphoid cells with a mitotic rate ranging from 5 to 62 per 20 high-power fields (hpf). A histologically distinctive variant with blastic cytologic features was identified (seven cases). The blastic variant was associated with a higher mitotic index (51.3 versus 19.0) and shortened survival (24.9 months). In contrast to the histologic progression often observed in follicular lymphomas, in no case was transformation to a large-cell or small noncleaved lymphoma observed. All cases had a mature B-cell phenotype demonstrating monoclonal Ig and B-cell surface antigens. Seventy-eight percent were CD5 positive; three of six CD5-negative cases presented in mucosal-associated extranodal sites. CD10 and CD25 were expressed in 52% and 44%, respectively, but did not show clinical correlations. The proliferative rate measured by Ki-67 positivity correlated with the mitotic index, but neither of these parameters had a statistically significant influence on survival.

Abdominal Neoplasms↗
PubMed1990

Are the IL-2 receptors expressed in the murine fetal thymus functional?

It is well established that the majority of murine fetal thymocytes (day 15 of gestation) express receptors for interleukin 2 (IL-2), but the functional significance of these IL-2 receptors (IL-2Rs) is not clear. In situ hybridization data show a developmentally regulated expression of IL-2 and IL-2R mRNA. IL-2 binding studies were performed on fetal thymocytes and the results show the presence of both high (kD approximately equal to 20 pM) and low (kD approximately equal to 10 nM) affinity IL-2Rs. These IL-2Rs are indeed functional: intact fetal thymic lobes (but not cell suspensions) cultured in IL-2 exhibited an in vitro proliferative response at 20 pM of IL-2, corresponding with the presence of a functional high-affinity IL-2R on fetal thymocytes. The IL-2-dependent growth was primarily observed in the IL-2R+ thymic subset, which contains the CD3-/CD4-/CD8- precursor thymocytes. Furthermore, in vitro blocking of IL-2 in intact fetal thymic lobes resulted in a reduction in the cell yield, which predominantly affected the expansion of the immature CD3-/CD4-/CD8- thymocytes. Our findings strongly support the concept that the IL-2/IL-2R pathway is responsible for the proliferation of precursor cells within the fetal thymus.

Animals↗
PubMed1990

Phase II trial of intermittent high-dose recombinant interferon alfa-2a in mycosis fungoides and the Sézary syndrome.

We previously demonstrated that recombinant interferon alfa-2a (IFN-alfa) in a dose of 50 X 10(6) U million units (MU)/m2 intramuscularly (IM) three times per week has efficacy against mycosis fungoides (MF) and the Sézary syndrome (SS). However, this regimen given to patients with refractory disease was uniformly complicated by toxicities requiring major dose reductions. The present study was designed to determine if intermittent high-dose IFN-alfa would preserve efficacy and decrease toxicity in a similar patient population. Twenty-four patients with advanced disease refractory to one or more standard therapies received IFN-alfa, 10 MU/m2 IM on day 1 followed by 50 MU/m2 IM on days 2 to 5 every 3 weeks; after the first four cycles, stable and partially responding patients underwent dose escalation to twice the starting dose. One complete (CR) and six partial responses (PRs) were observed (response rate, 29%; 95% confidence interval, 13% to 51%) lasting 4 to 19 months (median, 8 months). No improvement in objective response was seen in the eight patients who received dose escalation. Dose reductions were necessary in eight of 22 patients receiving one or more cycles of therapy. Weighted mean dose rate intensity for patients on this study over the first four cycles of treatment was 65.5 MU/m2/wk compared with 73.2 MU/m2/wk over the first 12 weeks of treatment in patients from the previous study, in which all 19 patients receiving more than 1 week of treatment required dose reduction. IFN-alfa is effective against previously treated MF and the SS and is better tolerated on this intermittent schedule.

Combined Modality Therapy↗
PubMed1990

Treatment of hairy cell leukemia with alternating cycles of pentostatin and recombinant leukocyte A interferon: results of a phase II study.

Fifteen patients with hairy cell leukemia (HCL) were treated with deoxycoformycin (pentostatin; dCF) (4 mg/m2 intravenous [IV] every week x 3) and recombinant interferon-alpha 2a (rIFN-alpha 2a) (3 x 10(6) units subcutaneously [SC] daily x 4 weeks) in alternating months for a total of 14 months. Eleven patients had undergone splenectomy; four had received prior systemic therapy with chlorambucil and/or steroids. All 15 are evaluable for toxicity and peripheral blood response, while 14 are assessable for bone marrow response. Toxicity was tolerable with grade 3 or 4 nausea and vomiting in three patients, neutropenic fevers in five, transient but significant depression in eight, and localized cutaneous herpes zoster in four. Circulating hairy cells were undetectable by the end of the first month in 10 of 13 patients, and by the end of the second month in the other three. Fourteen patients had bilateral bone marrow biopsies performed at baseline after 6 months of treatment, at the end of treatment (14 months), and at 6-month intervals during follow-up. Before treatment, all patients had hypercellular marrows with hairy cels replacing normal marrow elements; all showed at least a 95% clearing of their hairy cell infiltrate by 6 months of therapy. However, small collections of residual hairy cells could be detected intermittently on at least one side of bilateral samples in all patients. All patients have completed treatment with a median duration of follow-up off therapy of 27 months (range, 15 to 31 months). To date, all peripheral counts and serum soluble interleukin-2 receptor (sIL2R) levels remain stable, and no patient has had progression of the hairy cell infiltrate in the bone marrow. Although no patient achieved a pathologic complete response, alternating monthly cycles of dCF and rIFN-alpha 2a produced durable partial remissions (PRs) in all patients. Continued follow-up is required to determine the length of such remissions.

Adult↗
PubMed1990

Growth inhibition of a human lymphoma cell line: induction of a transforming growth factor-beta-mediated autocrine negative loop by phorbol myristate acetate.

Transforming growth factor-beta (TGF-beta) exerts profound inhibitory effects on a number of cell types, including normal B- and T-lymphocytes. In contrast, we have found a number of lymphoid tumor cell lines to be insensitive to the antiproliferative effects of TGF-beta 1 or TGF-beta 2. Binding and cross-linking with radioiodinated TGF-beta 1 demonstrated either low or absent expression of all three TGF-beta receptor species on three B-cell tumor lines, but T-cell and non-T, non-B tumors expressed large numbers of receptors. Treatment of the B-cell lines with phorbol 12-myristate 13-acetate (PMA) induced the expression of TGF-beta receptors and inhibited proliferation in all three lines in a dose- and time-dependent manner. The cell lines constitutively produced TGF-beta mRNA and released small amounts of latent TGF-beta; however, PMA induced the release of active TGF-beta. A neutralizing antibody to TGF-beta was able to reverse the PMA-induced growth inhibition of the malignant lymphoma cell line, RL, and addition of exogenous TGF-beta reversed the effect of the neutralizing antibody. Thus, TGF-beta can inhibit human lymphoma cell growth in vitro through an autocrine mechanism. Some lymphoma cells appear to have escaped from TGF-beta negative regulation by failing to express functional TGF-beta receptors and/or by failing to secrete active TGF-beta receptors and/or by failing to acts to inhibit lymphoma cell growth is by inducing the expression of TGF-beta receptors and the secretion of active TGF-beta, thereby reestablishing an autocrine growth-inhibitory loop.

B-Lymphocytes↗
PubMed1990

Treatment of Hodgkin's disease.

The available data support the hypothesis proposed by Smithers that Hodgkin's disease appears to be a systemic disorder of the lymphatic system. Standard treatments have been developed that cure approximately 70% of all patients who present to most institutions. Physicians should know the treatment approaches before proceeding with staging, because intelligent use of the best available treatment often obviates the need for staging laparotomy. At present, it is best that either chemotherapy or radiotherapy be used alone, except in patients who have massive mediastinal disease and for whom combinations of radiotherapy and combination chemotherapy are superior. Despite the long series of clinical trials conducted over the past two decades, no combination of four drugs has improved the results obtained with the original mechlorethamine-vincristine-procarbazine-prednisone program, when it is given in sufficient doses. It has been assumed that drug resistance of a specific type was the major reason for treatment failure. Attempts by physicians to overcome drug resistance, using alternating cyclical non-cross-resistant combination chemotherapy, have thus far not proved this approach to be superior to the use of a four-drug combination in full doses, and call into question this approach to testing the Goldie-Coldman hypothesis. Dose intensity has been a poorly controlled variable in virtually all clinical trials in Hodgkin's disease, and inadequate dosing may be the prime reason for treatment failure. This point has been highlighted by recent excellent results with marrow-ablative, high-dose chemotherapy and autologous bone marrow transplantation support for patients with very advanced "drug-resistant" disease. Investigators are now attempting to improve dose intensity by using more concentrated versions of standard drug combinations with colony-stimulating factors for support.

Antineoplastic Combined Chemotherapy Protocols↗