In the Working Formulation (WF), non-Hodgkin's lymphomas (NHL) are grouped according to their clinical behavior. These disorders are listed as entities defined by morphology, phenotype, and cytogenetics in the proposed Revised European-American Classification of Lymphoid Neoplasms (REAL), the clinical relevance of which is still debated. We analyzed 670 NHL cases included in two randomized clinical trials (EORTC 20855 WF-intermediate/high-grade and 20856 WF-low-grade malignancy) with histologic material available for review. Based on hematoxylin-eosin-stained sections, 77% of cases could be subtyped. Immunophenotyping was considered to be mandatory only in diagnosing T-cell lymphoma and anaplastic large-cell lymphoma. Of 522 cases subtyped, 11% were mantle cell lymphoma (MCL), 5% were marginal zone B-cell lymphoma (MZBCL), 46% were follicle center lymphoma, and 32% were diffuse large B-cell lymphoma. Statistical analysis and comparisons between classifications were made only within each trial and treatment group. MCL and MZBCL were characterized by a shorter median survival (3.4 and 4.1 years, respectively) in comparison with low- and intermediate-grade WF groups (> 9.3 and 5.8 years, respectively). In terms of progression-free survival, MCL showed a behavior similar to the low-grade group, with frequent relapses. Follicle center cell lymphomas behaved as low-grade lymphomas as defined by the WF and diffuse large B-cell lymphomas as the WF-intermediate grade group. Because several NHL entities have a clinical behavior of their own, their recognition by the REAL classification offers clinicians additional information that is not obtained when the WF is used.

To understand the role of the proinflammatory cytokine interleukin-1 (IL-1) in disease, investigators have studied how production of the different members of the IL-1 family is controlled, the various biologic activities of IL-1, the distinct and various functions of the IL-1 receptor (IL-1R) family, and the complexity of intracellular signaling. Mice deficient in IL-1Beta, IL-1Beta converting enzyme, and IL-1R type I have also been studied. Humans have been injected with IL-1 (either IL-1alpha or IL-1beta) for enhancing bone marrow recovery and for cancer treatment. The IL-1-specific receptor antagonist (IL-1Ra) has also been tested in clinical trials. The topics discussed in this review include production and activities of IL-1 and IL-1Ra molecules, the effects of IL-1 on gene expression, functions of cell-bound and soluble IL-1 receptors, the importance of the IL-1R accessory protein, newly discovered signal transduction pathways, naturally occurring cytokines limiting IL-1 production or activity, the effects of blocking cyclooxygenase and nitric oxide, and the outcomes of IL-1 and IL-1 Ra in human trials. Special attention is paid to IL-1beta converting enzyme and programmed cell death. The roles of IL-1 in hematopoiesis, leukemia, atherosclerosis, and growth of solid tumors are also discussed. This is a lengthy review, with 586 citations chosen to illustrate specific areas of interest rather than a compendium of references. At the end of each section, a short commentary summarizes what the author considers established or controversial topics linking the biology of IL-1 to mechanisms of disease.

Three unrelated Japanese patients with chronic nonspherocytic hemolytic anemia wer found to have marked deficiency of red blood cell (RBC) reduced glutathoine (GSH) (4.4%, 13.1%, and 6.9% of normal, respectively). A panel of RBC enzyme assays showed that one patient had decreased glutathione synthetase activity and the other two were moderately deficient in gamma-glutamylcystine synthetase. Some family members of each patient showed mild deficiency of the respective enzymes. RBCs of these patients also showed a decreased level of glutathione-S-transferase as in previously described GSH-deficient cases. Hemolytic anemia was their only manifestation, and neither 5-oxoprolinemia nor 5-oxoprolinuria, which are usually associated with to generalized type of glutathione synthetase deficiency, was noted in our patients.

Thrombopoietin is known to be essential for megakaryocytopoiesis and thrombopoiesis. Recently, we and others have shown that thrombopoietin induces rapid tyrosine phosphorylation of Jak2 and other proteins in human platelets and BaF3 cells, genetically engineered to express c-Mpl, a receptor for thrombopoietin. The Jak family of tyrosine kinases are known to mediate some of the effects of cytokines or hematopoietic growth factors by recruitment and tyrosine phosphorylation of a variety of Stat (signal transducers and activators of transcription) proteins. Hence, we have investigated whether Stat proteins are present in platelets and, if so, whether they become tyrosine phosphorylated in response to thrombopoietin. We immunologically identified Stat1, Stat2, Stat3, and Stat5 in human platelet lysates. Thrombopoietin induced tyrosine phosphorylation of Stat3 and Stat5 in these cells. Thrombopoietin also induced tyrosine phosphorylation of Stat3 and Stat5 in FDCP-2 cells genetically engineered to constitutively express human c-Mpl. Thus, our data indicate that Stat3 and Stat5 may be involved in signal transduction after ligand binding to c-Mpl and that this event may have a role in megakaryopoiesis/thrombopoiesis or possibly a mature platelet function such as aggregation.

There is a large increase in lymphoid malignancy in A-T patients and a total absence of myeloid tumors. Penetrance of the tumor phenotype is about 10% to 15% by early adulthood. The increase in lymphoid malignancy includes both B- and T-cell tumors. However, young A-T patients do not show an increased susceptibility to cALL, and the UK data suggest that B-cell lymphoma occurs in older A-T children. T-cell tumors may occur at any age and may be T-ALL, T-cell lymphoma, or T-PLL; most strikingly, there may be a fourfold to fivefold increased frequency of T-cell tumors compared with that of B-cell tumors in these patients. If this is correct, it is possible that a significant proportion of all T-ALL/T-cell lymphoma in infants might be associated with undiagnosed A-T. The age range and sex predominance for T-ALL may be different for A-T and non-A-T patients and the age range for T-PLL may also be different in A-T and non-A-T patients. There is clearly some uncertainty concerning the ratio of T-cell to B-cell tumors in A-T, but this could be clarified by the publication of all tumors that occur in the disorder. In contrast, 8 of 9 tumors reported in NBS, which shows the same cellular features as A-T, were lymphomas and none was a leukemia. There are several indicators of genetic heterogeneity in A-T that suggest that not all patients are equally susceptible to all T-cell tumor types. Concordance for tumor type within individual families suggests that particular gene defects may be associated with particular tumor types. The logical extrapolation of this argument is that some patients may not have any increased risk for B-cell tumors at all or even to all T-cell types but only to a particular type of T-cell tumor. What is the cause of the increased predisposition to leukemia/lymphoma in A-T patients? There is no evidence that the immunodeficiency in A-T is related to this predisposition. One of the major findings in all A-T patients is the increase in V(D)J-mediated chromosome rearrangement observed in T lymphocytes. Particular chromosome translocations in T cells, involving a break in a TCR gene, are characteristically associated with either T-ALL or T-PLL in non-A-T patients. The majority of T-cell tumors in A-T are T-ALL and T-cell lymphoma, about which virtually nothing is known chromosomally, and the assumption is that the increased number of translocations leads to the increased level of these tumors. In older T patients, the expansion of specific translocation T-cell clones has been followed to the point to which they develop into T-PLL. All the evidence, therefore, suggests that the A-T mutation in the homozygous state allows a large increase in production of translocations formed at the time of V(D)J recombination, and this leads to the increased predisposition to leukemia. The general increased predisposition to T-cell tumors compared with B-cell tumors in A-T patients may be related to a preferential occurrence of translocations in T cells. Relatively little is known about translocations in circulating B lymphocytes in normal individuals, but A-T siblings have been shown to have clonal chromosome rearrangements of both B and T cells, simultaneously, although in these siblings the T-cell clones occupied all the T-cell compartment and the B-cell clones were small. An important inference from these facts is that the A-T defect preferentially affects immune system gene recombination in T cells rather than B cells. Recent evidence suggests that the V(D)J recombination machinery is not identical or is not regulated identically in T- and B-cell progenitors. This finding is consistent with the hypothesis that V(D)J rejoining in the majority, at least, of A-T patients may be preferentially deficient in T cells compared with B cells giving rise to the greatly increased number of translocations and T-cell tumors. Carbonari et al proposed that the recombination defect in A-T cells affected both Ig isotype switching and TCR rearrangeme

Because hematopoietic cells express multiple Fc gamma receptor isoforms, the role of the individual Fc gamma receptors in phagocytosis has been difficult to define. Transfection of Fc gamma receptors into COS-1 cells, which lack endogeneous Fc gamma receptors but have phagocytic potential, has proved valuable for the study of individual Fc gamma receptor function. Using this model system, we have established that a single class of human Fc gamma receptor mediates phagocytosis in the absence of other Fc receptors and that isoforms from each Fc gamma receptor class mediate phagocytosis, although the requirements for phagocytosis differ. In investigating the relationship between structure and function for Fc gamma receptor mediated phagocytosis, the importance of the cytoplasmic tyrosines of the receptor or its associated gamma chain has been established. For example, two cytoplasmic YXXL sequences, in a configuration similar to the conserved tyrosine-containing motif found in Ig gene family receptors, are important for phagocytosis by the human Fc gamma receptor, Fc gamma RIIA. Fc gamma RI and Fc gamma RIIIA do not possess cytoplasmic tyrosines but transmit a phagocytic signal through interaction with an associated gamma subunit that contains two YXXL sequences in a conserved motif required for phagocytosis. The human Fc gamma RII isoforms Fc gamma RIIB1 and Fc gamma RIIB2 do not induce phagocytosis and have only a single YXXL sequence. Cross-linking the phagocytic Fc gamma receptors induces tyrosine phosphorylation of either Fc gamma RIIA or the gamma chain, and treatment with tyrosine kinase inhibitors reduces both phagocytosis and phosphorylation of the receptor tyrosine residues. Activation of protein tyrosine kinases follows Fc gamma receptor engagement of IgG-coated cells. The data indicate that coexpression of the protein tyrosine kinase Syk, which is associated with the gamma chain in monocytes/macrophages, is important for phagocytosis mediated by Fc gamma RI and Fc gamma RIIIA. Furthermore, phosphatidylinositol-3 kinase is required for phagocytosis mediated by Fc gamma RIIA as well as for phagocytosis mediated by Fc gamma RI/gamma and Rc gamma RIIIA/gamma.

Infectious complications are a major cause of morbidity and mortality after allogeneic bone marrow transplantation (BMT). We have evaluated the incidence of late infections (beyond day +50) in recipients of related (RD) and unrelated donor (URD) allogeneic BMT, factors associated with increased risks of infection, and the impact of the late infections on survival. Between 1989 and 1991, 249 patients received an RD (n = 151) or URD (n = 98) allogeneic BMT at the University of Minnesota and all late infections were investigated. Three hundred sixty-seven late infectious events developed in 162 patients between 50 days and 2 years after BMT. The incidence of any late infection was greater in URD versus RD recipients (84.7% v 68.2%, respectively; P = .009). In multivariate analysis, advanced graft-versus-host disease (GVHD) was significantly associated with late infections. The effect of GVHD was apparent only in RD recipients (relative risk [RR], 2.29; P = .003), whereas URD recipients, with or without GVHD, had more late infections compared with RD recipients without GVHD. Multivariate analysis showed that late posttransplantation infections were the dominant independent factor associated with increased nonrelapse mortality (RR, 5.5; P = .0001), resulting in improved 3-year survival for RD versus URD recipients (49.9% +/- 8% v 34.4% +/- 10%; P = .004). In this study, we observed that late infections are more frequent in URD recipients, resulting in substantially higher nonrelapse mortality. This prolonged period of increased infectious risk in URD recipients suggests the need for aggressive surveillance and therapy of late infections and perhaps prolonged antibiotic prophylaxis for all URD BMT recipients.

Between August 1985 and July 1994, we performed 115 volunteer unrelated donor (VUD) bone marrow transplants (BMT) for first chronic phase (n = 86) or advanced phase (n = 29) chronic myeloid leukemia (CML). Standard serologic HLA typing of potential donors and recipients was supplemented with one-dimensional isoelectric focusing (IEF) for class I proteins, allogenotyping for DR and DQ alleles using DNA restriction fragment length polymorphism (RFLP) analysis, and the measurement of antirecipient major histocompatibility complex (MHC) cytotoxic T-lymphocyte precursor cells in the donors' blood (CTLp assay). Recipients were conditioned for transplantation with a combination of high-dose chemotherapy and total body irradiation (n = 103) or high-dose chemotherapy alone (n = 12). Twenty eight recipients received ex vivo T-cell-depleted marrow, and 84 underwent some form of in vivo T-cell depletion. The probability of severe (grades III or IV) acute graft-versus-host disease (aGVHD) was 24%, and that of extensive chronic graft-versus-host disease (cGVHD), 38%. Proportional hazards regression analysis showed an association between low frequency CTLp and a reduced incidence of severe aGVHD (relative risk [RR], 0.28; P = .0035). The probability of relapse at 3 years was 23%, with first chronic phase disease being independently associated with a lower risk of relapse (RR, 0.71; P = .01). The overall leukemia-free survival (LFS) at 3 years was 37%; the LFS for the first chronic phase and advanced phase recipients was 41% and 26%, respectively. First chronic phase disease (RR, 0.56; P = .063) and the combination of recipient cytomegalovirus (CMV) seronegativity and an IEF-matched donor (RR, 0.48; P = .011) were both associated with improved LFS. The probabilities of survival and LFS for patients under 40 years of age transplanted in first chronic phase from an IEF-matched donor were 73% and 50%, respectively. We conclude that VUD BMT is a reasonable option for patients with CML; when using ex vivo or in vivo T-cell depletion, optimal results are achieved in patients transplanted in chronic phase with marrow from donors without demonstrable class I HLA mismatch and a low CTLp frequency.