摘要:

The effect of the tritiated thymidine (3H-TdR) suicide technique on the ability of donor cells to induce fatal graft-versus-host disease (GVHD) was studied. C57BL/6 (H-2b) spleen cells were stimulated in vitro with irradiated BALB/c (H-2d) Moloney lymphoma cells in mixed culture and3H-TdR of high-specific activity added to eliminate proliferating cells. The ability of such cells to induce fatal GVHD was assayed by injecting them i.v. into adult BALB/c mice immunosuppressed with cyclophosphamide (180 mg/kg). These cells induced fatal GVHD in fewer mice (52%) than did C57BL/6 cells cultured with BALB/c lymphoma cells but without3H-TdR (87%) and C57BL/6 cells cultured with irradiated C57BL/6 cells with (95%) or without3H-TdR (86%). Thus, the3H-TdR suicide technique greatly diminished the ability of cells to induce lethal GVHD.

ISSN:0041-1337    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Pooled serum from 6− to 8-week-old female Lewis × Brown Norwegian F1hybrid (LBNF1) rats undergoing acute local graft-versus-host (GVH) reactions was found to have the ability, when compared with normal F1serum, to increase node weight in a popliteal lymph node weight gain assay in syngeneic animals. Suspension of donor cells in normal F1serum on one side and corresponding concentrations of GVH serum on the contralateral side resulted in an average increase in popliteal node weight of 28.8% on the side receiving GVH serum. Of the 64 animals tested, 50 had larger nodes on the GVH serum side. This effect was not impaired by heating (56 C, 30 min) or by rapid freezing (-75 C) and thawing of the serum. Preinjection of the serum into the footpads 2 hr before donor cells also gave increased node weights as did injection of the serum i.p. In contrast, GVH serum was found to inhibit unidirectional mixed lymphocyte cultures of seven different allogeneic rat strain combinations, the inhibition ranging from 35 to 74%. In addition, the blastogenic cell responses of three different strains to phytohemagglutinin P were inhibited between 45 and 77%. The relationship between these two phenomena, in vivo increase in node weight and in vitro inhibition of blastogenesis, is not clear and is the object of further investigation.

ISSN:0041-1337    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Renal function studies 12 to 41 months after transplantation have been performed on seven cadaver renal allograft recipients who demonstrated immediate primary function after transplant (group A) and seven similar recipients who had delayed primary function (group B). The groups were matched as closely as possible for major physical characteristics and their postoperative management; in particular, only one patient had a post-transplant renal biopsy. Glomerular filtration rate determined by 24-hr creatinine clearance, endogenous creatinine clearance, and inulin clearance was usually lower in those patients having delayed primary function and they excreted more glucose per 24 hr and reabsorbed a smaller proportion of the filtered glucose load under infusion conditions. These results are discussed in relation to the effect of immediate and delayed primary function on the long-term prognosis of such patients.

ISSN:0041-1337    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Alloimmunization of mice with M locus-incompatible lymphocytes resulted in the generation of suppressor cells in the immunized host. Lymph node cells from such alloimmunized mice suppressed the in vitro cytotoxic response of normal cells to H-2 alloantigens. The suppression generated was greater than could be accounted for by dilution of the prekiller cell population with cells possibly devoid of cytotoxic potential from M locus preimmunized mice. Using M locus pseudocongenic mice, the suppressive effect was shown to be largely attributable to M locus determinants; restimulation of suppressor cells in culture with the specific M locus was required for suppression of effector cell generation. The in vivo effect of suppressor cells was tested in a graftversus-host reaction; injection of M locus preimmunized cells into footpads of F1hybrid mice suppressed the popliteal lymph node enlargement compared with lymph node size after injection of control preimmunized cells. Although the suppressive effect is mainly attributable to M locus determinants, incompatibility for the DBA/2 antigen may add to the suppression.The study of inhibitory effects on T cell cytotoxicity because of serologically undetectable lymphocyte-activating determinants (Mls) could lead to the better understanding of suppressive mechanisms which may allow the growth of syngeneic tumours.

ISSN:0041-1337    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

The present experiments tested the ability of hydrocortisone and methylprednisolone to alter the process of in vitro generation of cytotoxic T lymphocytes against specific alloantigens or to suppress the lytic phase of the subsequent cytotoxic reactions. The continuous presence of hydrocortisone in culture reduced the total number of cytotoxic lymphocytes recovered following their sensitization in mixed leukocyte cultures. However, corticosteroids had no direct effect on the processes required for generation of cytotoxic lymphocytes, since equal numbers of effector lymphocytes generated in the presence or absence of hydrocortisone produced equivalent, specific lympholysis. The addition of either hydrocortisone or methylprednisolone only during the cytolytic phase of cell-mediated lympholysis failed to significantly suppress the killing of lymphocyte targets. In contrast, parallel studies of the capacity of the same lymphocytes to serve as effector cells in antibody-dependent cellular cytotoxicity showed that both hydrocortisone and methylprednisolone directly inhibited the killing of Chang liver cells sensitized with low concentrations of antibody.

ISSN:0041-1337    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

In some cases success or failure of a proposed innovation in transplantation may be better judged if we consider the average survival time of the graft rather than the actuarial survival at a point in time. It is suggested that HLA matching may be an example of such a case and that the possible clinical benefits of modest improvements in matching may have been underestimated.Calculations are made which show that transplanting to the best match available in a pool of 100 patients might increase the expected graft survival time by more than 1 year.

ISSN:0041-1337    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Agarose is known to inhibit nonspecifically the cytotoxic effects of normal sera on xenogeneic lymphoid cells. To find an explanation for this agarose effect we have studied its requirements using guinea pig and human sera as the source of activity and rat thymocytes as target cells. Control assays were performed using heat-inactivated (56 C, 30 min) normal rat serum. The inhibitory effect of agarose was readily reproduced with untreated sera and also when sodium ethyleneglycoltetraacetate, a selective chelator of calcium ions, was added to the sera together with excess magnesium. However, the agarose effect failed to occur in the presence of 0.01 M EDTA unless magnesium ions were restored. Abrogation of cytotoxicity in human serum by incubation with a large number of target cells instead of agarose was also found to be magnesium dependent. Titrations of human serum, performed after absorption with agarose in the presence of EDTA, which does not interfere with antigen-antibody binding, and subsequent restoration of divalent cations, revealed no significant change in its cytotoxic titer when compared with that of mock-absorbed serum not subjected to the agarose treatment. Incubation of human serum with either agarose or rat thymocytes resulted in the conversion of factor B, essential for complement activation via the alternative pathway, previously shown to provide the complement activity necessary for the cytotoxic reaction. These results suggest that the agarose effect is mainly attributable to complement consumption via the alternative pathway rather than to the absorption of “natural” antibodies.

ISSN:0041-1337    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

The majority of skin tumors induced in mice by ultraviolet (UV) light are rejected when implanted into normal syngeneic recipients. Subcarcinogenic levels of UV light exposure render the normally resistant mice susceptible to tumor challenge. The immunoregulatory effect of UV light appears to be additive, since the growth rate of a tumor transplant is dependent upon the length of UV exposure administered prior to implantation. This suppressive influence does not appear to be directly mediated by the UV light, because the amputation of UV-irradiated tail skin allows for a retention of tumor resistance in otherwise tumor-susceptible hosts. UV-irradiated mice could also be immunized against UV tumors, which suggests that immune recognition of tumor-specific transplantation antigens has not been inhibited. The ability of UV exposure to alter normal immunological reactivity to UV-induced tumors is possibly an integral factor in the mechanism underlying UV carcinogenesis.

ISSN:0041-1337    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Rabbit antisera to rat thoracic duct lymphocytes were examined by absorption analysis with quantitative radioimmunoassays to determine the tissue distribution of the antigens recognised and the amount of antibody against different specificities. Seven of eight sera were remarkably specific for leucocytes and one serum was analysed in detail. In this serum about 70% of the antibody was leucocyte specific and most was against determinants on thymocytes, bone marrow cells, peripheral lymphocytes, and macrophages. This specificity is referred to as the leucocyte-common antigen. Smaller amounts of antibody were specific for antigens on peripheral lymphocytes but not thymocytes, and this could be subdivided into two antigens, one present on bone marrow cells and the other not.For preliminary biochemical analysis of the leucocyte-common antigen, thymocyte membrane was solubilized in deoxycholate. The homogeneity and apparent size of the antigen was determined by gel filtration and zone sedimentation on sucrose gradients. The activity behaved as a single component with the following hydrodynamic properties: sedimentation coefficient, 5.9S; partial specific volume, 0.71 ml/g; and Stokes radius, 7.5 nm. The molecular weight (including any bound deoxycholate) was calculated to be 172,000 and the frictional ratio 2.05. All activity bound to a lentil lectin affinity column and was eluted by methyl α-D-glucopyranoside, suggesting that the antigen is a glycoprotein.

ISSN:0041-1337    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Renal transplantation was performed in five adult patients with thrombotic microangiopathy, three of whom had had a bilateral nephrectomy prior to transplantation. The graft remained functional in three patients 72, 18, and 12 months after transplantation. One patient developed a thrombosis of the renal artery and one patient died from infection. There was no clinical or histological evidence of recurrence of thrombotic microangiopathy in the five patients after transplantation.Immunological investigations were performed in four of five patients before transplantation; C3 and C1q levels were low in two patients; serum C3-splitting activity and circulating immune complexes were present in all four patients and remained unchanged on haemodialysis and/or after bilateral nephrectomy. Complement abnormalities and immune complexes were not detected in the three patients with successful renal transplatation.

ISSN:0041-1337    

出版商:OVID    

年代:1977

数据来源: OVID