Graft-versus-Host reactions: a review

Pathology of graft-versus-host disease in the gastrointestinal tract

Graft-versus-host disease (GVHD), a common complication of hematopoietic stem cell transplantation, is a clinical syndrome that requires synthesis of clinical, laboratory, and histopathologic findings for diagnosis. The gastrointestinal (GI) tract is commonly affected, and pathologists must recognize subtle morphologic alterations in GI mucosal biopsies to make the diagnosis and to rule out other causes of GI dysfunction such as cytomegalovirus infection and drug effects. This review summarizes the histopathologic features of GVHD in the GI tract and outlines recent recommendations for reporting of GI biopsies with suspected GVHD.

Efficacy of transient treatment with FK506 in the early phase on cyclophosphamide-induced bone marrow chimerism and transplant tolerance across MHC barriers

BACKGROUND

The use of mixed allogeneic bone marrow chimerism to induce donor-specific transplantation tolerance has been extensively demonstrated. In the present study, we assessed the effect of combined use of a short course of FK506 and a single-dose cyclophosphamide (CYP) on the induction of tolerance and development of GVHD after allogeneic BMT.

MATERIALS AND METHODS

Lewis rat (RT1(l)) recipients received BMT from Brown Norway (RT1(n)) donors on the next day after injection of CYP at a dose of 200 mg/kg. The recipients were further treated with no FK506 (n = 8), 0.3 mg/kg/day FK506 on days 10-16 (n = 6), or the same dose of FK506 on days 0-6 (n = 6). In a subgroup of animals, heterotopic heart transplantation was performed to investigate transplantation tolerance.

RESULTS

Six of eight recipient rats that did not receive FK506 died of severe GVHD, while high levels of chimerism were induced. Recipients of FK506 in the later phase developed mild transient GVHD around 2 to 3 weeks after BMT and recovered thereafter; however, the level of chimerism was significantly decreased (2.8 +/- 2.3% on day 100). Treatment with FK506 in the early phase completely prevented the development of GVHD and induced stable allogeneic chimerism in the long-term (13.8 +/- 8.3% on day 100). These recipients with stable chimerism accepted subsequent BN heart allografts indefinitely (>200 days x 5), while rejecting third-party (BUF) heart allografts by day 12.

CONCLUSIONS

Early transient FK506 promotes the induction of stable bone marrow chimerism without GVHD after BMT with CYP pretreatment. The timing of treatment with FK506 is critical with a view to preventing GVHD and inducing stable long-lasting chimerism.

Chronic graft-versus-host disease

Chronic graft versus host disease (GVHD) remains today one of the most vexing late complications of allogeneic stem cell transplantation. Occurring a minimum of 100 days following stem cell transplantation, approximately 50% of patients will experience some degree of chronic GVHD. Host-reactive lymphocytes of donor origin are the cells responsible for the "alloimmune" attack. The increased use of hematopoietic stem cells collected from the peripheral blood instead of bone marrow and the increasing age of stem cell transplant recipients has led to a higher incidence of chronic GVHD. Chronic GVHD most commonly affects the skin, liver, eyes or the mouth, however multiple other sites may also be affected. Chronic GVHD and the medications used to treat it result in a profoundly immunocompromised state. Death due to severe chronic GVHD is usually a consequence of infectious complications. Standard treatment for severe chronic GVHD is a combination of cyclosporine and prednisone. An alternating day regimen of these two agents prolongs survival and reduces drug-related adverse events. Topical therapy to affected areas is preferred for patients with mild disease. The 10-year survival of patients with mild chronic GVHD is approximately 80%, but is less than 5% for patients affected by severe chronic GVHD.

Emergent autoimmunity in graft-versus-host disease

Donor T-cell recognition of host alloantigens presented by host antigen-presenting cells (APCs) is necessary for the induction of graft-versus-host disease (GVHD), but whether direct alloreactivity is sufficient for the propagation of GVHD is unknown. In this study, we demonstrate that GVHD cannot be effectively propagated through the direct pathway of allorecognition. Rather, donor T-cell recognition of antigens through the indirect pathway is necessary for the perpetuation of GVHD. Furthermore, GVHD results in the breaking of self tolerance, resulting in the emergence of donor T cells that can cause autoimmune disease in syngeneic recipients. Notably, GVHD-induced autoreactivity is donor APC dependent, transferable into secondary hosts, and involves cells of the innate immune system. These results indicate that donor T-cell--mediated pathologic damage during GVHD becomes donor APC dependent and provide a mechanistic explanation for the long-standing observation that GVHD is associated with autoimmune clinical manifestations.

Clinical impact of graft-versus-host disease against leukemias not in remission at the time of allogeneic hematopoietic stem cell transplantation from related donors. The Japan Society for Hematopoietic Cell Transplantation Working Party

Acute graft-versus-host disease (GVHD) increases post-transplant mortality and morbidity, but exerts a potent graft-versus-leukemia (GVL) effect. To clarify the impact of GVHD on outcome after transplant in aggressive diseases, patients with acute myeloid or lymphoblastic leukemia (AML, n = 366 or ALL, n = 255) in nonremission states, or chronic myelogenous leukemia (CML, n = 180) in accelerated phase (AP) or blastic crisis (BC), who received allogeneic hematopoietic stem cell transplantation (HSCT) from a related donor between 1991 and 2000, were analyzed. Significant improvement in overall and disease-free survival (DFS) was detected with grade I acute GVHD in AML (P = 0.0002 for overall survival and 0.0009 for DFS, respectively) and in CML (P = 0.0256 and 0.0366, respectively), while the trend towards improved survival was observed in ALL. Relapse rate was lower in grade I acute GVHD than in grade II in all three diseases, suggesting that treatment for grade II GVHD may compromise the GVL effect associated with GVHD. Chronic GVHD was found to suppress relapse in CML and ALL, but not in AML, although no improvement in survival was observed in any disease category. Our results suggest that treatment for grade II acute GVHD may need to be attenuated in transplant for refractory leukemias.

Redefining 'self': the role of microflora (commensals) mismatch in the development of GvHD after allogeneic stem cell transplantation and some possible remedies

The discovery of human leukocyte antigen (HLA) molecules and their role in allorecognition has facilitated the initiation of allogeneic stem cell transplantation in human beings. HLA mismatch to a large extent explains the phenomenon of graft rejection and graft versus host disease (GvHD). Incidence of GvHD even in syngeneic transplants suggests a role for extra genetic factors in the causation of GvHD. We hereby propose a hypothesis that the definition of 'self' (in the immunological sense) should be broadened to include both genetically determined molecules (e.g. HLA) and the microbial flora that colonize an individual. This hypothesis explains several observations about GvHD which can not fully be accounted for by the HLA mismatch theory and gives some clues towards circumventing GvHD.

Perinatal fetal-cell and gene therapy

Several inherited diseases can now be treated using postnatal or prenatal, in utero, transplantation of stem cells from the human fetal liver. Twenty-four patients with severe immunodeficiency diseases have been treated in infancy and three at the fetal stage, in our institution. We have also treated similarly 34 patients with inborn errors of metabolism or hemoglobinopathies. A total of 64% of all patients are alive with either full cure of their initial disease or at least significant benefit from the treatment. Immunological reconstitution can develop despite full mismatch between the stem cell donor and the recipient patient. Tolerance is acquired both towards donor and host antigens. Gene therapy is starting its development in some infants with an immunodeficiency related to a known gene defect and, in the future, it may be used in fetuses, immediately after the prenatal diagnosis of the gene abnormality.

Long-term persistence of IL-2-unresponsive allogeneic T cells in sublethally irradiated SCID mice

Donor T cells that are activated by host alloantigens initiate graft versus host disease (GVHD) but their long-term fate is poorly understood. The behavior of alloreactive donor T cells was studied in sublethally irradiated SCID mice. Intravenous injection of 10(6) allogeneic lymphocytes caused a severe form of GVHD, characterized by host hematopoietic atrophy. Fifty-fold fewer donor cells did not induce disease and were not simply rejected by radioresistant host mechanisms. Instead, low numbers of allogeneic T cells expanded 20- to 50-fold and remained for >1 year without causing evidence of GVHD. Persistent non-cycling donor cells with an activated phenotype were mainly found in the spleen. Tolerance was inferred by the recovery of host hematopoiesis, despite the presence of donor allogeneic T cells, and the inability of long-term persisting donor T cells to mediate cellular cytotoxicity or proliferate in response to exogenous IL-2 or antigenic stimulation in vitro. The TCR density of long-term persisting donor T cells was down-regulated. These findings suggest that the development of GVHD depends on the magnitude of the initial anti-host response. Subsequently donor cells differentiate, over several months, into a senescent-like state. This behavior questions the rationale for current treatment approaches to GVHD and is of relevance to any clinical situation where chronic T cell activation takes place in the absence of thymic development.

Graft-Versus-Leukemia Effect and Graft-Versus-Host Disease Can Be Differentiated by Cytotoxic Mechanisms in a Murine Model of Allogeneic Bone Marrow Transplantation

Allogeneic bone marrow transplantation (allo-BMT) is associated with both graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) effect. In the present study, we examined the contribution of cytotoxic effector mechanisms, which are mediated by tumor necrosis factor- (TNF-), Fas ligand (FasL), or perforin, to GVHD and GVL effect in a murine BMT model. Bone marrow cells plus spleen cells (BMS) from wild-type, FasL-defective, or perforin-deficient donors were transferred into lethally irradiated recipients in the parent (C57BL/6) to F1 (C57BL/6 × DBA/2) BMT model with or without prior inoculation of DBA/2 leukemia L1210 or P815 mast cytoma cells. The effect of anti–TNF- antibody administration was also examined. Whereas the defect or blockade of each cytotoxic pathway could ameliorate lethal acute GVHD, the GVL effect was differentially affected. The wild-type BMS recipients died of acute GVHD within 50 days without residual leukemia cells. The FasL-defective BMS recipients showed 60%< survival over 80 days without acute GVHD or residual leukemia cells. Administration of anti–TNF- antibody resulted in early leukemia relapse and the recipients died within 25 days with massive leukemia infiltration in the liver. The perforin-deficient BMS recipients died within 60 days with residual leukemia cells. These results suggest that blockade of the Fas/FasL pathway could be used for ameliorating GVHD without impairing GVL effect in allo-BMT.

Graft-Versus-Leukemia Effect and Graft-Versus-Host Disease Can Be Differentiated by Cytotoxic Mechanisms in a Murine Model of Allogeneic Bone Marrow Transplantation

Allogeneic bone marrow transplantation (allo-BMT) is associated with both graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) effect. In the present study, we examined the contribution of cytotoxic effector mechanisms, which are mediated by tumor necrosis factor- (TNF-), Fas ligand (FasL), or perforin, to GVHD and GVL effect in a murine BMT model. Bone marrow cells plus spleen cells (BMS) from wild-type, FasL-defective, or perforin-deficient donors were transferred into lethally irradiated recipients in the parent (C57BL/6) to F1 (C57BL/6 × DBA/2) BMT model with or without prior inoculation of DBA/2 leukemia L1210 or P815 mast cytoma cells. The effect of anti–TNF- antibody administration was also examined. Whereas the defect or blockade of each cytotoxic pathway could ameliorate lethal acute GVHD, the GVL effect was differentially affected. The wild-type BMS recipients died of acute GVHD within 50 days without residual leukemia cells. The FasL-defective BMS recipients showed 60%&lt; survival over 80 days without acute GVHD or residual leukemia cells. Administration of anti–TNF- antibody resulted in early leukemia relapse and the recipients died within 25 days with massive leukemia infiltration in the liver. The perforin-deficient BMS recipients died within 60 days with residual leukemia cells. These results suggest that blockade of the Fas/FasL pathway could be used for ameliorating GVHD without impairing GVL effect in allo-BMT.

Donor-specific unmodified bone marrow transfusion does not facilitate intestinal engraftment after bowel transplantation in a porcine model

BACKGROUND

The immunosuppression required to prevent rejection of intestinal transplants causes a high rate of infection and lymphoma. It is crucial that immunomodulatory strategies be developed to facilitate intestinal engraftment.

METHODS

We prospectively examined the effect of unpurified donor-specific bone marrow transfusions (DSBMTs) on rejection, infection, graft-versus-host disease (GVHD), and survival after intestinal transplantations in 44 Yorkshire Landrace pigs. Four groups that differed according to presence or abscence of treatment with FK506 and DSBMT were analyzed.

RESULTS

In nonimmunosuppressed pigs, DSBMTs had no effect on survival (8 days versus 9 days in controls; p = 0.9). In FK506 pigs, DSBMTs tended to reduce survival (21 days versus 37 days in FK506 controls; p = 0.1); no difference was seen between two bone marrow dosages 5 x 10(7) or 5 x 10(8) bone marrow cells/kg. No difference in the incidence of death caused by rejection was seen between DSBMTs and controls, but there was a marked tendency toward more deaths caused by rejection in DSBMTs + FK506 versus FK506-only pigs (p = 0.09). Daily stomal assessment showed a higher rate of moderate and severe interstitial rejection in DSBMT + FK506 versus FK506-only pigs; DSBMT was also associated with increased vascular rejection. Finally, groupwise comparison showed an order of susceptibility to lethal GVHD and infection as follows: DSBMT + FK506 > FK506 > DSBMT > controls.

CONCLUSIONS

Rather than promoting engraftment, DSBMT can sensitize recipients and cause rejection after intestinal transplantation. It aggravates the risks of generalized GVHD and infection and tends to reduce graft and recipient survival. Before being applied clinically, DSBMT needs to be refined to increase its tolerogenic potential without causing GVHD.

Effects of T cell adoptive transfer into nude mice on alveolar bone resorption induced by endotoxin

Using the method of reconstitution of nude mice with T cells, we examined the effects of T cell on alveolar bone resorption induced by repeated injections of Escherichia coli endotoxin into periodontal tissue. Three mice groups (normal, nude and T cell reconstituted nude mice) were used. Endotoxin derived from E coli was repeatedly injected into the gingiva of the mice left mandibles every 48 h and the mice were killed on the day after the 1st, 4th, 7th, 10th, 13th and 20th injections of endotoxin. Alveolar bone resorption was examined histopathologically and histomorphometrically. Bone surfaces in contact with the osteoclast were defined as the site of active resorption and the ratios of active resorption were compared among the 3 mice groups. Consequently, no active resorption was found after the first injection of endotoxin in any group. After the 4th injection, active resorption was found in normal mice and T cell reconstituted nude mice and gradually rose with the increase in the injection frequency. In contrast, few osteoclasts were found even after the 10th injection in the nude mice. In addition, there were statistically significant differences between the normal mice and nude mice after the 4th and 10th injections (p < 0.05). These findings suggested that T cell influences periodontal bone destruction induced by local administration of endotoxin during the early phases.

Cytotoxic T cells deficient in both functional fas ligand and perforin show residual cytolytic activity yet lose their capacity to induce lethal acute graft-versus-host disease

Graft-versus-host disease (GVHD) is the main complication after allogeneic bone marrow transplantation. Although the tissue damage and subsequent patient mortality are clearly dependent on T lymphocytes present in the grafted inoculum, the lethal effector molecules are unknown. Here, we show that acute lethal GVHD, induced by the transfer of splenocytes from C57BL/6 mice into sensitive BALB/c recipients, is dependent on both perforin and Fas ligand (FasL)-mediated lytic pathways. When spleen cells from mutant mice lacking both effector molecules were transferred to sublethally irradiated allogeneic recipients, mice survived. Delayed mortality was observed with grafted cells deficient in only one lytic mediator. In contrast, protection from lethal acute GVHD in resistant mice was exclusively perforin dependent. Perforin-FasL-deficient T cells failed to lyse most target cells in vitro. However, they still efficiently killed tumor necrosis factor alpha-sensitive fibroblasts, demonstrating that cytotoxic T cells possess a third lytic pathway.

Tonsil lymphoma presenting as tonsillitis after bone marrow transplantation

Bone marrow transplantation for the treatment of leukemia is increasingly successful in rendering patients disease free. However, it has become evident that the associated severe immunosuppression predisposes this population to an increased risk for other neoplastic disorders. We report on six patients in whom non-Hodgkin's lymphoma of the tonsillar region developed within 5 months after T-cell-depleted bone marrow transplantation for the treatment of leukemia at Memorial Sloan-Kettering Cancer Center from October 1990 to October 1992. These patients initially had what appeared to be infectious exudative pharyngitis/tonsillitis; however, they did not improve with medical therapy. Because of the persistence of pharyngitis/tonsillitis in association with cervical lymphadenopathy and odynophagia, the patients underwent definitive biopsy in the form of tonsillectomy, cervical lymph node biopsy, or both. Histopathologic review revealed non-Hodgkin's lymphoma. An association with Epstein-Barr virus has been noted in five of these patients. This article is aimed at alerting the clinician to consider the diagnosis of lymphoma in a patient with persistent pharyngitis/tonsillitis despite adequate medical therapy after bone marrow transplantation.

Graft-versus-host disease and the development of late complications

Graft-versus-host disease (GVHD) in both its acute and chronic forms is a severe complication after allogeneic marrow transplantation. GVHD is associated with structural and functional defects in many organs and tissues. Severe immunoincompetence may result in frequent, often severe and at times fatal infections caused by various organisms. Prolonged antibiotic prophylaxis, and possibly immunoglobulin administration are beneficial. Ocular complications, airway and pulmonary damage, and oral or dental problems may cause severe morbidity. Despite aggressive management, a proportion of patients will succumb to these complications. Severe skin disease and joint contractures are currently seen less frequently, mostly due to early treatment of the disease. Psychosocial rehabilitation of patients with chronic GVHD is a demanding and protracted challenge and should be approached by a multidisciplinary team.

Relevance of tumor necrosis factor to graft-versus-host disease after small bowel transplantation

The small bowel (SB), an organ replete with lymphocytes, may provoke graft-versus-host disease (GVHD) after transplantation (Tx). Since tumor necrosis factor (TNF) has been suspected of mediating the tissue lesions of GVHD, we sought to determine whether TNF could be detected in the serum of rats undergoing GVHD after SBTx or lymphocyte transfer. For this purpose, postoperative serum TNF activity was determined in Lewis x Brown Norway (LBNF1) hybrid rats suffering from GVHD after undergoing transplantation of an entire (group 1; n = 8) or a segmental (group 2; n = 4) Lew SB, or after i.p. injection with lethal doses (500 x 10(6)) of Lew lymphocytes (group 3; n = 3). Control LBNF1 received i.p. small doses (50 x 10(6)) of Lew lymphocytes (group 4; n = 4). Serum TNF activity was assessed using the WEHI bioassay. In rats with acute and lethal GVHD after entire SBTx (group 1) or injection with large doses of lymphocytes (group 3), TNF activity gradually increased and reached high levels by the time the rats were agonal. In segmental SBTx rats (group 2), GVHD was less severe than in entire SBTx rats. Similarly, the increase in TNF activity was less intense and only transient since it had returned to control levels by the time the rats had completely recovered from GVHD. In control rats primed with small doses of lymphocytes (group 4), GVHD did not occur and no increase in TNF activity was detected.(ABSTRACT TRUNCATED AT 250 WORDS)

Oral and nutritional status in allogeneic marrow recipients treated with T-cell depletion or cyclosporine combined with methotrexate to prevent graft-versus-host disease

To investigate how the use of T-cell-depleted marrow or a combination of cyclosporine and methotrexate to prevent graft-versus-host disease affect oral health and the ability to maintain adequate nutrition during the neutropenic phase after allogeneic bone marrow transplantation, 48 allogeneic bone marrow recipients were studied. From a group of adult leukemic marrow recipients of HLA identical sibling marrow, 23 patients were randomly chosen to receive T-cell-depleted marrow and 25 were selected to receive cyclosporine and four doses of methotrexate to prevent graft-versus-host disease. Before the transplantation, all patients were given all necessary dental treatment as well as oral hygiene and nutrition instructions. The oral mucosal and nutritional status in all patients (except one who died) were followed from 5 days before the procedure, during the neutropenic period after transplantation, and until discharge from the hospital. The number of oral lesions was similar in both groups. The subjective experience of orally related problems, such as pain from the oral cavity and number of days with total parenteral nutrition, was less in the T-cell-depleted recipients compared with those who received a graft-versus-host disease prophylaxis with cyclosporine and methotrexate (p less than 0.005). The oral cavity was considered to be the port of entry in four of six patients in the cyclosporine and methotrexate group who developed septicemia, compared with only one of six patients in the T-cell-depleted group with septicemia. The difference in the frequency of septicemia derived from the oral cavity did not, however, reach the significant level.(ABSTRACT TRUNCATED AT 250 WORDS)

CD3+ T cells in severe combined immunodeficiency (SCID) mice. V. Allogeneic T cells engrafted into SCID mice do not induce graft-versus-host disease in spite of the absence of host veto and natural suppressor cell activity

Intravenous injection of 10(6) to 10(7) non-fractionated spleen cells (SC) from C57BL/6 (B6, H-2b) mice into completely allogeneic, immunodeficient H-2d severe combined immuno deficiency (scid) mice leads to engraftment of allogeneic donor T cells. Mice analysed in the tenth week posttransfer had engrafted donor-type CD4+ and CD8+ T cells in the spleens but showed no clinical evidence of graft-versus-host disease (GVHD). Transfer of allogeneic T cells engrafted in scid recipients did not induce GVHD upon i.v. injection into secondary scid recipients and lead in most recipients to engraftment of a pure CD4+ T-cell population. Experiments were carried out to investigate the reason(s) for the lack of GVHD in recipient scid mice, i.e. the presence of allotolerance in the engrafted donor T cells. Scid spleen cells (SC) efficiently stimulated alloreactive responses of B6 T cells: scid SC stimulated H-2d-specific cytotoxic responses in a B6 anti-scid mixed lymphocyte culture in vitro, and scid SC injected i.v. into B6 mice efficiently primed splenic cytotoxic lymphocyte precursors against H-2d alloantigens. Moreover when assayed in vitro, no veto activity or natural suppressor activity was detectable in scid SC. These data demonstrate that tolerizing mechanisms currently believed to operate in vivo can not explain the fact that allogeneic T cells injected i.v. into immunodeficient scid mice become tolerized against host-type alloantigens. Our results are discussed in the light of clinical experience of allogeneic T-cell transfer in scid infants.

CD3+ T cells in severe combined immunodeficiency (scid) mice. IV. Graft-vs.-host resistance of H-2d scid mice to intravenous injection of allogeneic H-2b (C57BL/6) spleen cells

Intraperitoneal injection of 2 x 10(7) nonfractionated spleen cells (SC) from C57BL/6 (B6, H-2b) mice into completely allogeneic immunodeficient H-2d scid mice induced clinical and histological signs of acute graft-vs.-host disease (GVHD), with all transplanted severe combined immunodeficiency (scid) mice dying in the 3rd week post-transfer. In contrast four out of five scid mice survived for greater than 7 weeks after intravenous (i.v.) injections of equal numbers of B6 SC. Intravenously allotransplanted scid mice analyzed in the 8th week post-transfer had engrafted donor-type CD4+ and CD8+ T cells in the spleens but showed no clinical or histological evidence of GVHD. i.v. injection of 10(7) or 10(6)O B6 SC engrafted allogeneic T cells in spleens of scid recipients; in contrast, i.v. injection of 10(5) nonfractionated B6 SC or 3 x 10(5) cell sorter-purified, naive or anti-H-2d-primed splenic CD4+ or CD8+ B6 T cells led to rejection by young scid recipient mice. B6 T cells engrafted into spleens of scid mice after i.v. injection showed proliferative anti-host alloreactivity in vitro. No cytotoxic reactivity against host-type alloantigens was found in standard 4-h 51Cr-release assays. These data demonstrate that allogeneic T cells injected i.v. into immunodeficient scid mice are partially tolerized against host-type alloantigens.

Strong donor mononuclear cell reactivity for herpes simplex virus (HSV) antigen in HSV immune donors combined with recipient seropositivity for HSV is associated with acute graft-versus-host disease

Prior to bone marrow transplantation (BMT) titres of IgG antibodies for cytomegalovirus (CMV), herpes simplex virus (HSV) and varicella zoster virus (VZV) were analysed in 51 donors and recipients of allogeneic bone marrow. Donor mononuclear cells from peripheral blood and bone marrow cells were stimulated with antigen prepared from CMV, HSV and VZV. High IgG titres for HSV in the recipient were associated with grade II-III acute graft-versus-host disease (GVHD) (P = 0.05). Furthermore, the combination of positive IgG titre for HSV antibodies in the recipient, and strong donor blood mononuclear cell reactivity to HSV antigen in HSV immune donors, significantly increased the incidence of grade II-III acute GVHD (P = 0.04). The data suggest that HSV immune donor mononuclear cells may initiate a GVH reaction.

Variables predicting oral mucosal lesions in allogenic bone marrow recipients

One hundred and forty-eight (72%) of 205 allogenic bone marrow transplant recipients developed mucosal lesions in the oral cavity during the aplastic period after transplantation. Lesions were most frequent 8 to 9 days after transplantation. Factors that correlated with the development of mucosal lesions after univariate and multivariate analysis were a marrow cell dose of less than 3 x 10(8) cells/kg body weight, (p less than 0.0001), prolonged aplastic period (white blood cell count less than 0.2 x 10(9) cell/l during more than 14 days (p less than 0.005), herpes simplex virus-1 seropositivity of the recipient (p less than 0.01), and conditioning with total body irradiation (p less than 0.02).

Regulation of alloreactivity in vivo by a soluble form of the interleukin-1 receptor

In vitro studies have shown that cytokines are involved in the regulation of the immune response, but their role in vivo is less well defined. Specific cytokine antagonists enable the identification of particular cytokines involved in the response and offer a means for modifying it. Systemic administration of a soluble, extracellular portion of the receptor for interleukin-1 (sIL-1R) had profound inhibitory effects on the development of in vivo alloreactivity. Survival of heterotopic heart allografts was prolonged from 12 days in controls to 17 days in mice treated with sIL-1R. Lymph node hyperplasia in response to a localized injection of allogeneic cells was completely blocked by sIL-1R treatment. The inhibition was overcome by simultaneous administration of interleukin-1 (IL-1); thus, sIL-1R acts by neutralizing IL-1. These results implicate IL-1 as a regulator of allograft rejection and demonstrate the in vivo biological efficacy of a soluble cytokine receptor.

Influence of the length of the small bowel graft on the severity of graft versus host disease

The influence of the length and origin of a small bowel graft on graft versus host disease (GVHD) was studied in 33 (Lewis x brown Norway) F1 hybrids transplanted with different types of Lewis small bowel grafts. Recipients of an entire small bowel graft (N = 9), a jejunal graft (N = 6), or an ileal graft (N = 6) displayed a similar acute lethal GVHD, with 100% mortality rate and equivalent survival time (15 +/- 0.7, 16.8 +/- 0.9, and 16 +/- 0.6 days, respectively) (P greater than 0.01). On the other hand, 80% of the recipients of a segmental jejunal graft (N = 10) recovered from a transitory form of GVHD and regained weight similarly to the isografted rats (N = 4). It was concluded that the entire small bowel, jejunum, and ileum can provoke an equivalent GVHD after transplantation, whereas a segment of jejunum decreases the intensity of GVHD, probably by reducing the amount of transplanted lymphoid tissue.

Ocular complications of bone marrow transplantation

Thirty-four patients who had undergone bone marrow transplantation (BMT) were examined; 83.3% of those who received single shot and none of those who received fractionated total body irradiation (TBI) developed cataracts. The use of steroids to treat chronic Graft Versus Host Disease (GVHD) produced more severe cataracts in those who had allogeneic transplants after single shot TBI, but follow-up has not been long enough to assess their effect following fractionated TBI. Keratoconjunctivitis sicca (KCS) was seen in 81.8% of patients with chronic GVHD and in 33.3% of patients after autologous BMT.

Postoperative erythrodermia (POED), a type of graft-versus-host reaction (GVHR)?

Postoperative erythrodermia (POED) is a rare disease appearing several days after surgery for which blood transfusion has been required, characterized by erythrodermia, fever, pancytopenia, hepatic insufficiency or diarrhea. Most affected patients die within four weeks. The etiology remains unknown, but some assume it to be a type of graft-versus-host reaction (GVHR) caused by transfused lymphocytes. In this study, skin biopsies taken from 9 POED patients were examined to clarify whether POED is a type of GVHR. In seven samples, changes compatible with GVHR, such as lymphocyte infiltration in the basal layer and occasional eosinophilic or vacuolar degeneration of the epidermal cells, with occasional satellitosis, were noted. Immunopathologically, infiltrating lymphocytes mostly expressed suppressor/cytotoxic T cell markers like those in GVHR. Meanwhile, immunostaining with anti-HLA-A type specific antibodies failed to differentiate infiltrating lymphocytes from host cells. Thus, the present morphologic and in vivo marker study suggested POED to be a type of GVHR, while in vivo HLA-A typing showed two contradictory possibilities: first, that POED is a GVHR in which major histocompatibility antigen-matched donor lymphocytes attack host cells, and secondly that POED is not a GVHR, the infiltrating lymphocytes being of host origin.

The pathology of combined heart-lung transplantation: an autopsy study

Clinical heart-lung transplantation (HLT) began at Stanford University (Stanford, CA) in 1981, and since then, over 40 HLTs have been performed. There is now a worldwide total of 250 HLTs. While much of the pathology that occurs in patients receiving an HLT is similar to that which develops in patients with other transplanted organ systems, these patients also develop unique clinical complications and pathologic processes that deserve emphasis. We report the autopsy findings of 20 HLT recipients, of whom 12 died in hospital one day to 4 months post-HLT. A major contributing factor in five of these postoperative deaths was pleural hemorrhage from adhesions due to prior chest surgery. Overwhelming viral and fungal infections accounted for six deaths. The seventh patient died as a result of adult respiratory distress syndrome (ARDS). Two patients showed histologic evidence of the reimplantation response. Six long-term survivors died (mean survival, 22 months) with obliterative bronchiolitis (OB). In four patients, OB was the immediate cause of death, while one patient died of an intercurrent myocardial infarct, and the other patient died of complications from an appendectomy. Two long-term survivors died without OB, one of iatrogenic causes at 63 months and the second due to unexplained ARDS at 52 months. Both patients without OB had virtually normal underlying pulmonary parenchyma. All of the long-term survivors had either coronary arterial or pulmonary vascular intimal sclerosis, and renal lesions attributable to cyclosporine A toxicity. Although histologic features of mild acute pulmonary and cardiac rejection were observed in four patients overall, these did not contribute to the cause of death in any case. Although OB is a major threat to its success, HLT is a viable option for patients with endstage pulmonary disease.

Angiogenic activity by spleen cell supernatants from tumor-bearing and tumor-resected mice

Supernatants of cultured spleen cells (SCS) from small tumor-bearing mice (STBM) and large tumor-bearing mice (LTBM) are able to enhance tumor growth as well as accelerate tumor takes in vivo when inoculated 24 h before tumor implant. After tumor resection enhancing activity disappears at a rate depending on the size of the resected tumor. Spleen cells from tumor-bearing mice also evoke a complex vascular response, lymphocyte-induced angiogenesis (LIA) elicited via the release of lymphokines from activated T cells. As angiogenic factors promote tumor development we investigated if SCS from tumor-bearing and tumor-resected mice contain factors capable of evoking a LIA response. Angiogenic activity was detected by SCS of small and large tumor-bearing mice as well as in large tumor-resected mice. On the other hand, SCS from small tumor-resected mice are not able to evoke an angiogenic response. Possibly, the large antigenic burden in LTRM stimulate the immune system in a different way than in STRM. We can suggest that the different behavior of spleen cells after small and large tumor removal can be explained by quantitative or qualitative changes in the spleen subpopulations.

Hematopoietic factors in graft-versus-host reaction

Graft-versus-host (GVH) reaction has a curious unsolved area in the immunopathogenesis and pathophysiology of the immunohematopoietic system, and GVH disease remains one of the major obstacles in clinical allogeneic bone marrow transplantation. T lymphocytes and T lymphocyte subpopulations are now recognized to be initiators of this GVH reaction and disease. Also, T lymphocytes are known to be accessory cells in the regulation of hematopoiesis, and produce a variety of lymphokines relevant to hematopoiesis. Admittedly, remarkable hematopoietic changes can be found in GVH reaction, but the cellular mechanisms underlying these changes are so complex they have yet to be fully elucidated. In fact, elevated serum levels of myeloid and erythroid colony-stimulating activities were found in mice suffering from GVH disease in which marked granulopoiesis and suppression of erythropoietic differentiation were seen. In addition, each granulocyte/macrophage colony-stimulating factor (GM-CSF) or burst-promoting activity (BPA) could be detected in sera from patients with GVH disease following allogeneic bone marrow transplantation. There seems to be at least two mechanisms involved in the control of hematopoiesis with either humoral or local environmental factor, probably via the T lymphocytes or T lymphocyte subpopulations activated by alloantigens or autologous non-T cells.

Specific suppression of the in vitro parent anti-hybrid reaction. I. Characterization of a suppressor cell induced in hybrids by pretreatment with parent-strain spleen cells

Spleen cells from B6D2F1 hybrid mice pretreated with 5 X 10(7) B6 spleen cells iv 7 days earlier (B6-pretreated B6D2F1) exhibit a reduced capacity to stimulate the in vitro proliferative and anti-D2 CTL responses of B6 spleen cells. This inability of B6-pretreated B6D2F1 spleen cells to stimulate B6 spleen cells efficiently is due neither to the absence of stimulating cells bearing the D2 alloantigens nor to the destruction of B6 responding cells, but to the presence in the B6-pretreated B6D2F1 cell population of a suppressor mechanism, since the addition of B6-pretreated B6D2F1 spleen cells to a culture of normal B6 responding and irradiated B6D2F1-stimulating spleen cells can suppress the B6 anti-B6D2F1 response. This suppression is mediated by a nylon adherent, Thy-1-negative cell of parent-strain origin which is radioresistant at 2000 R. This suppressor cell is not induced by the injection to B6D2F1 hybrids of spleen cells from the other parent strain (D2) or an allogeneic strain (C3H). It does not suppress either the response of the other parent (D2) or an allogeneic strain (C3H) to B6D2F1 antigens, or the response of B6 cells to an allogeneic strain (C3H).

Specific suppression of the in vitro parent anti-hybrid reaction. II. Parameters influencing suppressor cell induction in the F1 hybrid

In the accompanying paper (K. Kosmatopoulos et al., Cell. Immunol. 104, 319-334, 1987) we have reported that the spleens of B6D2F1 hybrids pretreated with B6 spleen cells 7 days earlier contain a cell which specifically suppresses the in vitro proliferative and cytotoxic B6 anti-B6D2F1 responses. The results we present here concern the in vivo conditions under which this suppressor cell can be induced. Suppressor cell activity appears early after the injection of B6 spleen cells (day +1), increases on Day 7, and disappears by Day 30; it is always detectable after the injection of 5 X 10(7) B6 spleen cells and never after the injection of 1.25 X 10(7) cells, the intermediate dose of 2.5 X 10(7) cells being followed by variable results. This variability is attributable to the age of B6 donor and B6D2F1 recipient mice, and suppression is never observed when 2.5 X 10(7) spleen cells from 6-week-old B6 mice are injected into 6-week-old B6D2F1 hybrids. The suppressor cell is induced by the injection of B6 spleen cells of the Thy-1+ Ly-1-2+ phenotype, even if they are irradiated at 1000 R just before their injection. Lymph node cells from B6 mice induce the suppressor cell, whereas thymocytes do not. Irradiation of B6D2F1 hybrids at 600 or 950 R does not prevent the induction of suppressor cell, nor does thymectomy. Moreover, in the thymectomized or 600 R-irradiated B6D2F1 animals suppression can be induced even by the injection of only 1.25 X 10(7) B6 spleen cells. This phenomenon of specific suppression is not limited to the B6-B6D2F1 genetic combination since it has been observed in all parent-hybrid combinations tested to date.

Survey of experimental data on fetal liver transplantation

Fetal liver transplantation has been shown to induce hematological and immunological reconstitution in irradiated rodents, dogs, horses, and sheep. Engraftment and reconstitution without GvHD has been readily obtained using histocompatible donors. When mismatched fetal donors were used, a comparatively larger number of donor cells was required, in addition to pre-treatment of host with higher doses of irradiation or irradiation plus chemotherapy. Stem cell suspensions devoid of any T lymphocyte can be transplanted across major histocompatibility barrier without inducing overt GvHD. The transplanted animals become tolerant to both donor and host grafts.

Sustained recovery of hematopoiesis and immunity following transplantation of fetal liver cells in dogs

We studied the ability of fetal liver cells to reconstitute hematopoiesis and immunity in lethally irradiated dogs. Engraftment and sustained lymphoid and hematopoietic recovery was achieved when the recipients received a preparative regime of high-dose total body irradiation (TBI) alone followed by transplantation of DLA-identical fetal liver. The combination of high-dose TBI and cyclosporine allowed engraftment in DLA-mismatched fetal liver transplants. Typical features of graft-versus-host disease (GvHD) did not occur although autoimmune-like syndromes (myasthenia gravis, immune thrombocytopenia) were observed in some recipients. Hematopoietic recovery was rapid and complete. Recovery of T- and B-lymphocyte function was comparatively delayed, but sufficient to prevent opportunistic infections after the initial 3 months post transplant. These data indicate that cells from a single fetal liver can reconstitute hematopoiesis and immunity in DLA-mismatched recipients and suggest that human fetal liver cell transplantation may be an effective source of stem cells for patients who lack an HLA-identical donor for bone marrow transplantation.