Peripheral blood leukocyte grafts that induce human to mouse graft-vs.-host disease reject allogeneic human skin grafts.

Allogeneic graft-versus-host disease is characterized by skin, gut, and bile duct destruction by relatively few donor type lymphocytes. In contrast, we can now show that human-to-mouse xenogeneic graft-versus-host disease is characterized by vasculitis and tumor-like infiltrations of the murine lymphohemopoietic organs with many human CD25+, HLA-DR+, CD4+ lymphoblasts. Using the technique of serial transplantation, it appears that at least 90% of the human lymphoblasts were unreactive to murine tissues. It is demonstrated consistently that the donor type lymphoblasts induced typical allogeneic rejection of distantly located full thickness human unmatched fetal skin grafts. The fact that the human grafts show primary immune responses in vivo indicates that the graft-versus-host disease murine model may be suitable for vaccination studies.

Efficient replication of human immunodeficiency virus type 1 and measles virus in a human-to-mouse graft versus host disease model permits immunization research.

An acute graft versus host disease (GvHD) murine model was developed to study the pathogenic and protective mechanisms against viruses that replicate in cells of the human immune system. The model allowed efficient replication of lymphotropic, macrophage and amphitropic strains of human immunodeficiency virus type 1 (HIV-1) and measles virus (MV). Cytopathic lymphotropic strains of HIV-1 and a wild-type MV strain replicated in a 'burst'-like manner, whereas a non-cytopathic lymphotropic HIV-1 strain and all macrophage-tropic HIV-1 strains caused persistent infection of the graft. The replication kinetics of infection with these viruses were highly reproducible and were very similar to those observed in natural infection of humans. Infection with these viruses, with the exception of HIV-1SF2, led to a delay [corrected] and abrogation of the GvHD, indicating a direct immunosuppressive effect. Interestingly, infection with the lymphotropic HIV-1SF2 strain was rapidly and spontaneously abrogated. The model was also shown to be suitable for the evaluation of passive immunization strategies. Administration of a combination of antibodies against the HIV-1 V3 loop and the HIV-1 CD4 binding sites prevented subsequent infection with HIV-1IIIB. In contrast, administration of CD4 binding site specific human monoclonal antibody at a concentration that would neutralize the virus in vitro enhanced in vivo infection with HIV-1IIIB. The model also allowed evaluation of in vivo immunization studies. Immunization with a live attenuated measles vaccine resulted in protection from a wild-type MV challenge, whereas immunization with a subunit candidate vaccine appeared to give partial protection.

Cytokine dependence of human to mouse graft-versus-host disease.

Human peripheral blood leucocytes (PBL) induce chronic graft versus-host disease (GvHD) in non-conditioned severe combined immunodeficient mice. Chronic GvHD was observed in such animals after transplantation of 6 x 10(7) human PBL per g body weight. However, acute xenogeneic GvHD results from grafting at least 2 x 10(7) human PBL per g body weight to heavily conditioned murine hosts. The large numbers of human PBL were thought to be required to produce above threshold amounts of certain cytokines. We show that treatment of the recipient mice with human interleukin 2 reduces the number of cells to inflict acute GvHD by a factor of ten. Human T cells and not B cells or macrophages, were previously shown to generate acute xenogeneic GvHD, when selected cell types from peripheral blood were grafted. Most of the infiltrating cells had the CD4+ phenotype. We demonstrate that CD4+ T cells are the main mediator, as the disease is abrogated by treating the mice with cytotoxic CD4 antibodies, but not with CD8 antibodies. A survival pattern, similar to that seen in GvHD, was induced by transplantation of a Herpesvirus saimiri transformed human CD4+ clonal T cell line in conjunction with daily interleukin 2 injections. Herpesvirus saimiri transformed human T cells allow easily reproducible graft properties in chimeric mouse models for human diseases.

The role of natural antibodies and ABO (H) blood groups in transplantation of human lymphoid cells into mice.

Recently, evidence was presented that natural antibodies (NAb) are a crucial barrier to human cellular engraftment in severely immunosuppressed normal mice (Eur. J. Immunol. 1992. 22: 197.). In this report we show that normal mouse serum contains low titers of NAb against human cells of blood groups type O (H) and B and high titers against human cells of blood group A. Accordingly, human peripheral blood leukocytes (PBL) of group O (H) and B donors could be grafted successfully into normal BCBA mice (H-2b/k) following irradiation with high dose total body irradiation (TBI). PBL of blood group type A donors did not engraft in normal mice but could be transplanted without difficulty in B cell-deficient CBA/N mice which lack NAb, after conditioning with high dose TBI. Treatment of lethally irradiated normal BCBA mice with cobra venom factor (COF), which eliminates the third factor of complement, and liposomes containing dichloromethylene diphosphate (Cl2DMP), which eliminates macrophages, resulted in engraftment of human blood group type A PBL. This implies that the NAb barrier for discordant xenogeneic cell transplantation can be abrogated. A method utilizing directly labeled probes and flow cytometry is described for the quantitation in mouse serum of NAb, reacting with human cells. Using sera of H-2b/k mice we show that murine NAb react with human stem cells, granulocytes, lymphocytes and monocytes of blood group A and only weakly with similar cells from blood group O (H) and B donors. Sera of H-2b, H-2d and H-2k mice of different ages and microflora possess NAb against human erythrocytes of blood group type A and occasionally demonstrate weak titers against erythrocytes of blood groups B and O (H) and the Rhesus factor.

Detection of migrated allogeneic oligodendrocytes throughout the central nervous system of the galactocerebrosidase-deficient twitcher mouse.

Galactocerebrosidase-deficient oligodendrocytes of 'twitcher' (twi/twi) mice degenerate prematurely. Transplantation of normal bone marrow cells has been shown to alleviate symptoms and to prolong survival time. However, characteristic ataxia ('twitching') is not cured. In an attempt to improve further the condition of twitcher mice, allogeneic foetal liver cells were transplanted as a source of normal haemopoietic stem cells and supplemented with intracerebral transplantation of foetal brain cells. A reliable method was developed to detect donor-type cells in brain tissue. Bacteriophage lambda transgenic foetal mice were used as donors of both foetal liver and brain cells. Integrated copies of lambda DNA in donor cells were detected by in situ hybridization with biotinylated probes, which were then stained using streptavidin alkaline phosphatase. This technique was combined with immunohistochemistry to distinguish donor-type oligodendrocytes from macrophages. Immunoperoxidase staining with an antiserum to carbonic anhydrase-II produced dark perikarya of oligodendrocytes. The results demonstrated that local foetal brain cell grafts resulted in a wide dissemination of donor-type oligodendrocytes throughout the twitcher brain. The addition of a foetal brain cell graft to haemopoietic cell transplantation resulted in significantly prolonged survival of twitcher mice.

Determination of the origin and nature of brain macrophages and microglial cells in mouse central nervous system, using non-radioactive in situ hybridization and immunoperoxidase techniques.

The origin and nature of brain macrophages and microglial cells in the mouse central nervous system (CNS) were investigated. First, the expression and localization of determinants recognized by the different monoclonal antibodies (mAbs) MOMA-1, Mac-1-alpha, and F4/80 (raised against cells of the mononuclear phagocyte system) were immunohistochemically studied in the developing and adult mouse brain. In order to clarify the origin of brain macrophages and microglial cells, we used bacteriophage lambda transgenic mice as donors for bone marrow transplantations in recipient mice of different ages. During ontogeny, numerous MOMA-1-, Mac-1-alpha-, and F4/80-positive blood monocyte-derived brain macrophages (amoeboid microglia) infiltrated the CNS parenchyma. These brain macrophages gradually disappeared from the brain parenchyma at postnatal day 7 (P7). From P17 on, Mac-1-alpha- and F4/80-positive cells were detected within the brain parenchyma with the morphology of resting microglial cells. Transitional forms between brain macrophages and "resting" microglia were not observed in the developing brain. Combined non-radioactive in situ hybridization and immunohistochemistry revealed many MOMA-1-positive bone marrow-derived brain macrophages that were located in the leptomeninges, the ventricles, and occasionally the blood vessel walls. These results show that brain macrophages are of bone marrow origin. Many "resting" microglial cells were detected in the brain, mainly in the white matter. It appeared that about 10% of these cells displayed the transgenic signal. This result indicates that the majority of "resting" microglial cells are of local, presumably neuroectodermal, origin.

Acute human vs. mouse graft vs. host disease in normal and immunodeficient mice.

Recent reports of persistent engraftment of human lymphocytes and myeloid cells in hereditary immunodeficient severe combined immunodeficient mice (SCID) and beige athymic nude X-linked immunodeficiency (Bg/Nu/XID) mice have raised the question of why attempts to graft human cells into artificially immunosuppressed normal mice have failed so far. In the present study we provide evidence that this difference is due to the absence of natural antibodies in the mutant mice. We demonstrate that human PBL can be grafted in normal mice immunosuppressed by heavy doses of total body irradiation, provided the transplant is performed when the recipients lack natural antibodies in their serum, e.g. as in newborn normal mice, in mice treated with anti-mouse IgM antibody from birth, and in 3-week-old B cell-deficient CBA/N mice. In all cases, large numbers of human PBL were required. Under these conditions an acute and fatal graft vs. host disease (GVHD) developed in the recipients, regardless of whether these were artificially immunosuppressed or hereditary immunodeficient. The clinical manifestations and the histopathology of this xenogeneic acute GVHD are quite different from those of allogeneic GVHD. The former is primarily confined to the hematolymphoid tissues and locations close to accumulations of proliferating lymphoblasts, such as the peritoneal cavity in case of i.p. transplantation. The discordant xenogeneic GVHD is induced by human T lymphocytes and can be abrogated by treatment with anti-human T cell serum.

Medical care and postmodern management.

Because of the persistent influences of modern philosophies of management, health care has suffered from a monomania for economic thinking in a world thought of as a simple, unchanging machine. This form of management fails in the Netherlands, even in its own economic terms. We argue that best management is postmodern management and is inspired by postmodern thinking. It assumes that there is a non-reducible plurality of forms of life in human society which mostly interact in a powerful and complex way. It, therefore, stresses simplicity and dynamics in structure making. It advocates the principle of freedom, within constraints, for the staff of the medical organization. As a paradigm of new management we suggest the deconstruction of the present piecework payment per activity of doctors: it is static, expensive and fails to control the quality of medical care. Instead, two dynamic structures are suggested consisting of a payment per treated patient, together with the creation of a limited number of teams of highly qualified medical controllers. Both of these measures should improve the quality of health care as well as its cost-effectiveness.

Immunophenotyping of non-Hodgkin's lymphoma. Correlation with relapse-free survival.

In a retrospective analysis the authors studied the relation between the immunologic phenotype of B-cell non-Hodgkin's lymphoma (NHL) and disease-free survival. The phenotype included immunoglobulin isotypes; B-cell maturation/differentiation antigens of clusters of differentiation CD9, CD10, CD19-24, CD37, CD38; T-lymphocyte antigens in CD5-7; HLA-DR; peanut agglutinin binding capacity; terminal deoxynucleotidyl transferase; the activation marker CD25 (interleukin-2 receptor); and the proliferation marker transferrin receptor. The phenotype and clinical data were available for 109 patients. Two patients underwent bone marrow transplantation, and 15 patients (with low or intermediate grade NHL) did not receive treatment intended to achieve complete remission. These 17 cases were excluded from the analysis. For individual markers, CD23 expression was associated with a longer actuarial disease-free survival (50% survival in CD23-positive cases was 40 months; and in CD23-negative cases, 16 months; P = 0.01). Among the total study population of 92 patients, this finding applied in particular to those with a low-grade malignancy according to the Kiel classification (P = 0.03). In high-grade NHL (Kiel classification) the absence of CD38 or presence of CD24 on tumor cells correlated with a higher degree of disease-free survival (P values 0.009 and 0.04, respectively). For a combination of five CD markers associated with stages in physiologic B-lymphocyte maturation/differentiation (CD9, CD10, CD21-23), the lowest measure of disease-free survival was observed where NHLs were at an immature stage, and the greatest extent of survival where NHLs were associated with a resting B-cell stage (P = 0.006). These statistical significances aside, the detailed immunologic phenotyping has relatively little prognostic value when compared with that of the malignancy grade assessed by conventional histopathology.

The glomerular tip lesion: a distinct entity or not?

Howie and Brewer recently described a novel glomerulopathy: the glomerular tip lesion (GTL). The characteristic feature of this entity is a collection of intracapillary foam cells and marked vacuolization of the epithelial cells of the glomerular segment adjacent to the origin of the proximal tubule. Although this lesion resembles focal segmental glomerulosclerosis (FSGS), Howie and Brewer suggested that it constitutes a distinct entity, differing also clinically from FSGS, in that it would have a better response to steroid treatment. We treated five patients fulfilling the criteria of Howie and Brewer. However, neither corticosteroids (1.5 mg/kg/day for 1 month in five patients) nor cyclosporin-A (5 mg/kg/day for three months in four patients) caused a decrease in proteinuria to below 4 g/day. In two patients, renal function deteriorated and in one of them, recurrence of classical FSGS was found in the renal transplant. A sixth patient was observed in whose biopsy a combination of GTL with membranous glomerulopathy was present. We conclude that GTL is not a distinct entity and that in the clinical course and response to treatment it does not differ from FSGS.

Immunophenotyping of non-Hodgkin's lymphoma. Lack of correlation between immunophenotype and cell morphology.

The establishment of Clusters of Differentiation for T- and B-lymphoid cells during International Workshops on Human Leukocyte Differentiation Antigens prompted the authors to evaluate the immunophenotypes in 160 cases of non-Hodgkin's lymphoma (NHL). In this group, 130 were of B-lymphocyte lineage (117 by monotypic immunoglobulin expression), and 30 of T-cell lineage. In the B-NHL series the expression of immunoglobulin isotypes, B-cell maturation/differentiation antigens of CD9, CD10, CD19-24, CD37, and CD38 (OKT10), HLA-DR and peanut agglutinin binding showed no significant relationship with histopathologic diagnosis as defined by the Kiel classification. Of the T-cell markers, CD5, CD6, and CD7 showed lineage promiscuity by their presence on some B-NHL. Conversely, the authors grouped the cases according to phenotypes (either CD antigens or immunoglobulin isotypes) which occur in distinct stages of (physiologic) B-cell maturation/differentiation. Eighty-six of the 130 cases could be fitted according to CD phenotype expression. This approach did not yield a significant relationship between phenotype and individual histopathologic categories either. The staging by CD phenotype and by immunoglobulin isotype yielded different results in this respect. Most B-NHL had an intermediate stage of B-cell maturation/differentiation. In the T-NHL series most cases showed a phenotype (CD1-CD8, CD38, TdT, and peanut agglutinin binding capacity) compatible with mature T-lymphocyte characteristics. The exceptions were lymphoblastic convoluted lymphomas, which exhibited an immature immunophenotype. It is concluded that NHL in distinct histopathologic categories are heterogeneous in immunologic phenotypes, and that the immunophenotype of lymphoma cells has no evident association with that of their presumed counterparts in physiologic cell maturation/differentiation.