Some but not all benefits of intravenous immunoglobulin therapy after marrow transplantation appear to correlate with IgG trough levels

Multiple benefits of intravenous immunoglobulin (IVIG) therapy after marrow transplantation have been reported, including decreased incidence of acute graft-versus-host disease (GVHD), infection, sepsis, cytomegalovirus (CMV) pneumonitis and platelet use. To test the hypothesis that the observed beneficial effects of IVIG are related to the serum IgG levels achieved, we followed IgG levels (pre-infusion, 1 h and 24 h post-infusion) in 45 consecutive marrow transplant recipients. IVIG 500 mg/kg was given weekly for six doses starting day -8 pre-transplant, then every other week for a total of 11 doses. Forty-one patients (22 allogeneic, 17 autologous, two syngeneic) were evaluable. Patients with acute GVHD had significantly lower serum IgG trough levels (less than 1200 mg/dl) noted at day +20 post-transplant and afterwards than patients without GVHD (greater than or equal to 1200 mg/dl). Pharmacokinetic modeling of the data indicates that IgG half-life between day -8 and day +6 may predict which recipients are at increased risk of acute GVHD. Allogeneic recipients in the group with trough levels less than 1200 mg/dl required more platelet transfusions. Although there was no significant difference in fungal infection rates or bacteremia, sepsis was noted in only two recipients (one allogeneic, one autologous), both with serum IgG trough levels less than 1200 mg/dl. In addition, three allogeneic recipients had cytomegalovirus pneumonitis, all in the group with lower IgG trough levels. Thus, while serum IgG trough levels less than 1200 mg/dl appear to be strongly associated with acute GVHD, low levels may also be associated with increased platelet utilization, with cytomegalovirus pneumonitis, and sepsis, but not with the overall incidence of infection.

Transfusions shortly before HLA-matched marrow transplantation for leukemia are associated with a decrease in chronic graft-versus-host disease

The effect of random red cell transfusions given shortly before allogeneic bone marrow transplantation (BMT) was evaluated in 969 leukemic patients transplanted from an HLA-identical sibling donor. Patients were divided into two groups: 501 who received a transfusion shortly before BMT, and 468 who did not. Both groups had a similar incidence of acute graft-versus-host disease (GVHD), but the recently-transfused group had a significantly lower incidence of chronic GVHD (35.9% vs 48.9%). These differences remained significant in a multivariate analysis of time to chronic GVHD (p = 0.022), taking into account other differences between the two groups and known risk factors for chronic GVHD.

Conditioning-related toxicity and acute graft-versus-host disease in patients given methotrexate/cyclosporine prophylaxis

Intensive chemoradiotherapy conditioning regimens and acute graft-versus-host disease (GVHD) are both associated with significant morbidity and mortality after bone marrow transplantation. In this study, we investigated whether the conditioning regimen affected the development of acute GVHD. Thirty-four patients, four with severe aplastic anemia and 30 with a lymphohemopoietic malignancy, were prepared for transplantation either with cyclophosphamide (CY) alone, with CY combined with total body irradiation (TBI) or CY combined with etoposide and either TBI or busulfan. GVHD prophylaxis included methotrexate (MTX 10 mg/m2) given on days 1, 3 and 6, and daily cyclosporine (CSP) on days--1 through 180. The overall incidence of acute GVHD was 36% (15% for HLA identical, 87% for HLA non-identical recipients). However, when assessed by the severity of conditioning regimen-related toxicity, the incidence of GVHD grades II-IV (HLA identical; HLA non-identical) was 0% (0%; 0%), 37% (20%; 67%) and 50% (22%; 100%) for patients with mild, moderate and severe toxicity, respectively. Compliance with GVHD prophylaxis declined with increasing intensity and toxicity of the conditioning regimen. These data suggest that a regimen of three doses of MTX and daily CSP is as effective as four doses of MTX/CSP for GVHD prophylaxis in patients given HLA identical marrow grafts. However, GVHD regimen compliance and efficacy of GVHD prevention are inversely related to the intensity of the conditioning regimen.

Inhibition of cluster formation and lymphocyte proliferation by anti-fibronectin antiserum

Dendritic cells (DC) confer concanavalin A responsiveness to accessory cell-depleted canine lymphocytes. DC-lymphocyte cluster formation is followed by blast transformation and proliferation of lymphocytes. We investigated whether fibronectin, which is known to be involved in cell:cell interactions, might also be involved in the interaction between canine DC and lymphocytes. The addition of rabbit anti-dog fibronectin antiserum to concanavalin A-stimulated peripheral blood mononuclear cells decreased cluster formation and reduced 3H-thymidine incorporation by 57-70%. Similarly, when cell fractions, enriched for DC, were pretreated with anti-fibronectin antiserum before being added back to accessory cell-depleted lymphocytes, cluster formation was reduced and lymphocyte proliferation after concanavalin A stimulation decreased by 18-46% as measured by 3H-thymidine uptake. Ferritin-conjugated anti-fibronectin antibody was bound to the surface of DC, primarily at the dendritic processes. We conclude that fibronectin, located on the surface of canine DC, participates in the accessory cell function of these cells.

Transfusion-induced graft-versus-host disease in patients with malignant lymphoma. A case report and review of the literature

A case of transfusion-induced graft-versus-host disease (GVHD) occurring in a 31-year-old female with Hodgkin's disease in complete remission is reported. Clinical features are similar to 19 other reported cases of transfusion-induced GVHD associated with malignant lymphoma. The lack of relationship with underlying histology or disease stage and the nearly uniformly fatal outcome underscores the importance of prophylactic irradiation of blood products given to patients with malignant lymphoma undergoing therapy.

Effective ultraviolet irradiation of platelet concentrates in teflon bags

Several plastic materials used in blood storage were evaluated for their ability to transmit ultraviolet B (UVB) light. A plastic bag manufactured from sheets of transparent Teflon efficiently (78-86%) transmitted UVB light and was employed in subsequent functional studies of lymphocytes and platelets exposed to UVB light while contained in these bags. In vitro experiments showed a UVB dose-dependent abrogation of lymphocyte responder and stimulator functions, with concurrent preservation of platelet aggregation responses. In a phase I pilot study, UVB-treated platelet concentrates were administered to four bone marrow transplant recipients. Adverse effects attributable to the transfusions were not observed, and patients showed clinically effective transfusion responses. No patient developed lymphocytotoxic HLA or platelet antibodies. These studies suggest that platelets can be effectively irradiated with UVB light in a closed system. However, numerous variables, including container material, volume and composition of contents, steady exposure versus agitation, and exact UV wavelength, must be considered.

Processing and storage of human bone marrow: a survey of current practices in North America

We conducted a two-step survey to question 110 transplant centers in the United States and Canada regarding marrow processing and storage policies and procedures. Approximately 65% of the centers surveyed responded to the questionnaires. Major differences with respect to patient diagnoses, amount of marrow harvested, purging method applied, freezing procedure, storage bag, cell concentrations, storage duration, interval until transplantation, cell counting, viability determination and so forth were reported. Among those centers responding 13% stored not only autologous but also allogeneic marrow. There was no consensus regarding patient consent for duration of storage, coverage of cost for cryopreservation or utilization of stored marrow after a patient's death. Additional studies will be necessary to correlate in vitro methods of marrow storage with clinical transplantation results, and to determine the cost/benefit ratio of this approach to various diagnoses. This should provide the basis for the establishment of standards and should facilitate the approach to various ethical questions.

Ultraviolet B-induced loss of HLA class II antigen expression on lymphocytes is dose, time, and locus dependent

Ultraviolet B (UVB) irradiation interferes with the afferent and efferent loops of the immune response. One mechanism that has been suggested is the decline of class II histocompatibility antigen expression on the cell surface. However, data in the literature are controversial. In the present study, we examined the effect of UVB light (peak emission at 302 nm), at doses of 0.05-300 mJ/cm2, on class II antigen expression on normal peripheral blood lymphocytes enriched for non-T cells. Monoclonal antibodies directed at nonpolymorphic determinants on HLA-DR, -DQ, and -DP were used to label cells before and at time intervals up to 72 h after irradiation. Immediately following UVB exposure, fluorescence intensity for all three antigens was equal to or slightly increased above control values. Subsequently, there was a decline in antigen expression that was UVB dose dependent and varied for HLA-DR, -DP and -DQ. Although there was only a very moderate loss of surface labeling for HLA-DR up to 72 h, there was a steep decline for HLA-DQ and -DP. There was no significant decline in class II antigen expression on cells exposed to 2000 or 4000 cGy of gamma irradiation. Also, there was no effect of either gamma or UVB irradiation on class I antigen expression. These data explain some of the discrepancies in previous reports on the effects of UVB on class II antigens; they show not only a dose effect but also an effect of time after exposure and, most importantly, the class II antigen under study.

Inhibition of the enzyme purine nucleoside phosphorylase (PNP) reduces refractoriness to transfused platelets in a dog model

To better define the role of T-cells in alloimmunization, we induced purine nucleoside phosphorylase (PNP) deficiency in a dog platelet transfusion model. Short-term administration of eight different drug schedules using several combinations of the PNP inhibitor 8-aminoguanosine and/or deoxyguanosine did not induce significant toxicity in four treated animals as demonstrated by blood chemistries, cell counts, and autologous platelet recovery and survival measurements. However, continuous long-term daily administration of these agents produced significant renal and/or hepatic toxicity leading to death in five of six animals. Modification of the drug schedule to early short-term administration of both deoxyguanosine and 8-aminoguanosine, followed by long-term intermittent doses of only 8-aminoguanosine, was not only well tolerated by all the animals but also resulted in significant immunosuppression. Overall, six of nine evaluable dogs (67%) treated with some combination of PNP inhibitors did not become refractory to eight weekly transfusions of platelets from a single random donor dog, P less than 0.005, compared to untreated controls, only 3/21 (14%) not immunized. Furthermore, in four evaluable recipients, discontinuation of the 8-aminoguanosine while continuing platelet transfusions from their original donors did not result in refractoriness. In addition, these four recipients were also unable to recognize platelets from two other random donors. This suggests that both specific and non-specific tolerance to foreign platelet antigens had been induced by PNP-inhibitor therapy. Other evidence for the efficacy of this immunosuppressive treatment was the almost normal post-transfusion recovery and survival of donor platelets, both during and after treatment. This suggests failure to form even low levels of platelet alloantibodies in the immunosuppressed recipients. In contrast, B-cell immunity to soluble antigens was intact as demonstrated by a normal antibody response to keyhole limpet haemocyanin (KLH) antigen.

Management of acute graft-versus-host disease

Current graft-versus-host disease (GVHD) prophylaxis is not uniformly successful. Since the development of GVHD has a profound impact on transplant success, treatment is required. The mainstay of therapy has been glucocorticoids (steroids), along with anti-thymocyte globulin, cyclosporine, monoclonal antibodies, and aggressive supportive care, resulting in response rates of 30-50%, dependent upon severity of the disease, type of transplant, underlying diagnosis, prophylaxis given and other factors. Dose intensification or combinations of agents may increase response rates (60-80%), however, without necessarily improving survival, due to intervening complications. Nevertheless, patients with complete responses have a higher probability of survival, and a subgroup of patients will not develop chronic GVHD. As our understanding of cell recruitment, cell interactions and cytokine networks improves, new strategies are likely to be developed. The sequential use of antibodies directed at different cell populations or cytokines, along with anti-inflammatory measures, may be helpful. Prevention of GVHD has to remain our objective; however, efforts at therapy must continue until that goal is achieved.

Delayed complications and long-term effects after bone marrow transplantation

Bone marrow transplantation is being used with increasing frequency and success for an expanding number of indications. At present, more than 1000 patients are surviving more than 5 years and several hundred more than 10 years after transplantation. Extended observation periods have shown that numerous complications have to be expected in these patients, particularly in those given TBI as part of the conditioning regimen. However, other factors including chemotherapy, GVHD, viral infections, host environment, and genetic factors also contribute to the problem. It has been pointed out by critics of bone marrow transplantation that success is often reported as disease-free survival, meaning survival in remission. However, there are, obviously, secondary problems that can significantly impair patients' quality of life, even though their leukemia (or lymphoma) is in unmaintained remission. Very few data on quality of life in long-term surviving patients have been reported. Several studies are currently ongoing (Forman S, Blume K, personal communication), and the results are urgently needed. It will also be of interest to compare patients given, allogeneic transplants with those given autologous marrow infusions in an attempt to determine to what extent conditioning regimens and alloreactivity contribute to long-term side effects. It will be even more important to design regimens that are less likely to induce these problems and to design therapeutic approaches to treat complications effectively.

Incapacitating peripheral neuropathy as a manifestation of chronic graft-versus-host disease

A 35-year-old caucasian man developed mild and transient signs of chronic graft-versus-host disease (GVHD) 5 months after bone marrow transplantation. At 16 months he presented with painful cramps in hands, feet, and truncal muscles. Electrophysiological studies revealed generalized sensory neuropathy. There was occasional fasciculation and high frequency motor units during involuntary muscle contractions, and agonist/antagonist cocontractions of peripheral muscle groups (non-continuous). A sural nerve biopsy showed Schwann cells and macrophages with myelin debris, and Schwann cell stacks with collagen pockets. The patient's symptoms responded to treatment with glucocorticoids and azathioprine. We propose that this patient's incapacitating polyneuropathy was a major manifestation of chronic GVHD, suggesting that the peripheral and possibly central nervous systems can be targets of chronic GVHD.

Batten's disease: failure of allogeneic bone marrow transplantation to arrest disease progression in a canine model

We investigated whether the course of canine ceroid lipofuscinosis (CCL), a model of Batten's disease in man, was affected by allogeneic bone marrow transplantation. Four English setters with CCL, 4 1/2 months of age, were given 9.2 Gy of total body irradiation, followed by the infusion of bone marrow cells from healthy DLA identical sibling donors. All transplanted dogs had complete hematologic reconstitution. However, at 12-13 months posttransplant, all dogs developed characteristic and progressive signs of CCL. Autopsies revealed cerebral atrophy and findings of ceroid storage not different from those in non-transplanted controls. These findings suggest that bone marrow cells do not contain or release the gene product(s) necessary to correct the disease. It appears unlikely that with our current knowledge, allogeneic marrow transplantation would be beneficial in the treatment of Batten's disease.

Cluster formation of canine dendritic cells and lymphocytes is calcium dependent and not inhibited by cyclosporine

Canine peripheral blood mononuclear cells (PBMC), dendritic cells (DC), and lymphocytes either alone or in combination were cultured with concanavalin A (ConA), calcium ionophore, and phorobol-12-myristate-13-acetate (PMA), and examined for lymphocyte/DC cluster formation and lymphocyte proliferation as determined by thymidine uptake. ConA- or calcium ionophore-stimulated proliferation of PBMC required the presence of normal DC, and was preceded by cluster formation of DC and lymphocytes. PMA-triggered proliferation was not preceded by cluster formation but also required the presence of normal DC. The presence of ultraviolet (UV)-irradiated rather than normal DC did not permit ConA-, calcium ionophore-, or PMA-triggered lymphocyte proliferation. Addition of interleukin 2 (IL-2) to cultures of lymphocytes and UV-irradiated DC restored responsiveness to PMA, suggesting that a decrease in cytokine production was the central event in UV-induced accessory cell inhibition. Cyclosporine, known to interfere with IL-2 release and responses, completely blocked both ConA- and PMA-induced lymphocyte proliferation but did not interfere with ConA-triggered cluster formation. Verapamil blocked both cluster formation and proliferation. These data show that DC/lymphocyte cluster formation is Ca2+ dependent and cannot be inhibited by cyclosporine. The data show, furthermore, that in agreement with findings in other species, triggering of canine lymphocytes by lectins and phorbol esters follows distinct pathways.

Prevention of transfusion-induced graft-versus-host disease in dogs by ultraviolet irradiation

Ten dogs were given 9.2 Gy of total body irradiation and autologous bone marrow infusion followed by ten daily transfusions of leukocytes for a total of 11.5 to 36.2 (median, 18.8) x 10(8)/kg obtained via leukapheresis from histoincompatible unrelated donors. Four dogs were given unirradiated leukocytes, and all developed graft-versus-host disease (GVHD). In contrast, only two of three dogs given leukocytes irradiated with 20 mJ/cm2 of ultraviolet (UV) light (200 to 300 nm), and none of three dogs given leukocytes irradiated with 1,000 mJ/cm2 developed GVHD. These data indicate that UV irradiation abrogates the alloreactive potential of transfused leukocytes, and suggest that UV irradiation can be used to prevent the development of transfusion-induced GVHD.