Search PubMed⌕ Search

Biomedical subjects

A Ting

Publications and source records attributed to A Ting.

At least 145 records · Page 8Linked to original sources
PubMed1977

Renal transplantation and B-cell cross-matches with autoantibodies and alloantibodies.

Of 51 cadaveric kidneys transplanted between June, 1976, and June, 1977, 18 were transplanted in the presence of a positive cross-match against the donor's B lymphocytes. 11 of these positive cross-matches were due to alloantibodies and 7 due to autoantibodies. Autoantibodies were defined not only on the basis of autoreactivity with B lymphocytes but also by their absent or restricted reactivity with lymphocytes from patients with chronic lymphocytic leukaemia. Transplants in 8 of 11 patients with a positive alloantibody-B-cell cross-match and in 6 of 7 patients with a positive autoantibody-B-cell cross-match were successful at 3 months. These success-rates were no different from those found in patients with a negative B-cell cross-match. Thus, renal allografts may be performed with a reasonable assurance of success in the presence of a positive B-cell cross-match whether due to autoantibodies or to alloantibodies.

Antibodies, Heterophile↗
PubMed1977

Correlation of HLA and thyroid antibodies with clinical course of thyrotoxicosis treated with antithyroid drugs.

The prevalence of HLA-B8 in thyrotoxic (Graves' disease) patients who relapsed after withdrawal of antithyroid drugs was high (69%) compared with that in patients who remained in remission (40%) and in healthy controls (28%). B8-positive patients were 1-8 times more likely to relapse after withdrawal of drug therapy than B8-negative patients. The persistence of thyroid microsomal antibodies after withdrawal of therapy correlated significantly with the presence of HLA-B8. This association was more pronounced in patients who remained in remission. From this it might be assumed that B8 is also associated with the persistence of thyroid T.S.H. (thyroid-stimulating hormone) receptor stimulating antibodies. In view of these findings, it is suggested that patients who are thyrotoxic might be typed for HLA, and those who are B8-negative could be given a trial of long-term antithyroid drug therapy.

Adolescent↗
PubMed1977

Renal transplantation and a positive serological cross-match.

A renal transplant involving a recipient with a positive serological cross-match against donor lymphocytes generally results in hyperacute rejection of the graft. 13 cadaveric renal transplants were performed in recipients with a known positive serologic cross-match against donor B lymphocytes. 12 of these serological cross-matches were positive against donor blood, node, or spleen lymphocytes, but the reactivity was directed against donor B lymphocytes only. 3 transplants failed, 2 because of rejection and 1 because of renal-artery thrombosis. 10 transplants are functioning, 6 to 42 weeks after the operation. Of these 10 successful grafts, 3 had no acute rejection episodes, while 7 had an early acute rejection episode which responded to treatment. Histologically, the grafts showed a cellular rejection, similar to that in enhanced renal allografts in the rat. It is possible to transplant a kidney in a high-risk patient with a positive B lymphocyte cross-match with a low risk of failure. In addition active enhancement of the graft might sometimes occur.

Acute Disease↗
PubMed1977

Human B-lymphocyte antigens expressed by lymphocytic and myelocytic leukemia cells. II. Detection by human anti-B-cell alloantisera.

The majority of human lymphocytic and myelocytic leukemia cells express a polymorphic antigen that is found on peripheral blood B-lymphocytes and cultured lymphoblastoid B-cell lines. These B-lymphocyte antigens were detected by 34 human alloantisera that were repeatedly absorbed with pooled platelets to remove all activity against HLA antigens and T-lymphocytes. Absorption studies indicated that a common antigen was present on both B-lymphocytes and positive leukemia cells. Leukemia cells could be subdivided into two groups based on the presence of the B-lymphocyte antigen. Fourteen of 18 acute myelocytic leukemia cells, 10 of 13 acute lymphoblastic leukemia cells, 4 of 6 chronic myelocytic leukemia cells, and 2 of 2 chronic lymphocytic leukemia cells were positive. This group of leukemia cells also reacted with rabbit anti-B-cell sera raised to papain digests of spleen cell membranes. F(ab')2 fragments of the rabbit antsera were shown to specifically block the reactions of the human antisera against B-cells and leukemia cells. These results suggested that the rabbit and human anti-B-cell sera were reacting with identical molecules. This conclusion was supported by immunoprecipitation data.

Adult↗
PubMed1977

Development of Rh-specific maternal autoantibodies following intensive plasmapheresis for Rh immunisation during pregnancy.

Two cases of autoantibody formation following large volume plasmapheresis for rhesus immunisation during pregnancy are described. In each case the autoantibody was directed against the Rh complex but showed a preference for G-positive cells. It is postulated that repeated plasmapheresis in the presence of persistent antigenic stimulation has removed a feedback inhibition of the immune response. The specificity of the alloantibody has broadened resulting in cross-reactivity against self-antigens. The possible implications of these cases in relation to autoimmunity are discussed.

Adult↗
PubMed1976

Multiple sclerosis and high incidence of a B lymphocyte antigen.

Multiple sclerosis patients were tested for six new antigens present on human B lymphocytes. The group 4 specificity occurred in 83.9% of the 56 patients as compared to 32.5 percent in 72 healthy controls (P less than .003). The antiserums defining the five other B lymphocyte specificities reacted at a lower frequency to B cells from multiple sclerosis patients, showing that increased reactivity to group 4 antiserum was specific. Linkage of a hypothesized multiple sclerosis susceptibility gene with certain haplotypes of HLA-A3, HLA-B7 HLA-DW2, and the new B group 4 can be inferred.

Alleles↗
PubMed1976

Anti-B lymphocytotoxins in renal-allograft rejection.

To determine the possible role of the B lymphocyte alloantigen system in renal-transplant rejection, we examined serum specimens from 81 allograft recipients for cytotoxic activity against a panel of normal B lymphocytes. Specimens from 22 of 25 recipients undergoing allograft rejection demonstrated strong B-lymphocyte cytotoxicity whereas only 13 of 56 recipients with normal allograft function showed similar B lymphocyte cytotoxocitiy (P less than 0.0001). In the serum samples of recipients with graft rejection who were followed sequentially, B-lymphocyte cytotoxicity preceded or was concurrent with the onset of functional impairment. The results show that anti-B-lymphocyte antibodies are associated with rejection, but it is quite possible that they are the products of rejection rather than the cause.

Antibodies↗
PubMed1976

B-lymphocyte alloantigens in Caucasians.

Human B lymphocytes have been shown to have at least five polymorphic specificities defined by 32 antisera. The antisera were produced by absorption with pooled platelets to remove HLA activity and were selected out of over 400 tested sera. The sera that defined the five specificities had high correlation coefficients within a group (generally in the range of 0.6-0.9). As shown by the fit in the Hardy-Weinberg equilibrium, the five specificities appear to be determined by alleles at one genetic locus. No association between these specificities and HLA was noted.

Alleles↗
PubMed1975

Lymphocyte-dependent antibody cross-matching for transplant patients.

Cadaver donor transplant patients who had a negative complement-dependent cytotoxicity cross-match test were tested in parallel with the specific donor at the time of transplantation by the lymphocyte-dependent antibody (L.D.A.) test. Transplants were performed on the basis of negative standard and long (2-5-hour) ment-dependent cross-match tests and the results of the L.D.A. test were withheld from the transplant centres. Of the 57 transplants tested, 49 had a negative L.D.A. result with 74 percent one-month function whereas 8 had a positive L.D.A. Result with 25 percent one-month function (P smaller than 0-02). When the results were further divided into methods of preservation of donor kidneys, among L.D.A.-Negative transplants, of the 20 kidneys preserved by Collins Sacks solution, 95 percent were functional at one month, whereas of the 28 kidneys preserved on the Belzer machine, 64 percent were functional at one month (P smaller than 0-05). The risk of the most hazardous period of transplantation (i. e., the first month) may be reduced drastically by simple preservation methods and the se of L.D.A. cross-matching.

Antibodies↗
PubMed1975

HL-A in cancer family "N".

Actual HL-A typing has been performed on 115 members of cancer family N, a large kindred (over 1000 members ascertained) showing the findings consistent with the cancer family syndrome. In the cancer-prone line (branches C and D) of the family, 20 of 21 members with cancer had one HL-A haplotype, HL-A2-HL-A12 (relative odds = 6.30), including some decreased family members who had haplotypes assigned. Eleven of 12 family members with cancer in branches C and D, actually typed, had HL-A2-HL-A12 (relative odds = 6.06). The single exception showing cancer and another haplotype in branch D is a child of a family member with haplotype HL-A2-HL-A12.

Female↗
PubMed1975

Utilization of cultured human lymphoid cells for detection of humoral sensitization in prospective recipients of kidney transplants.

Prospective recipients of kidney transplants were tested for lymphocytotoxicity; from these we selected 102 sera that lacked cytotoxic antibodies against peripheral lymphocytes from at least 80 unrelated subjects. To detect humoral sensitization, we then reacted these with 17 cultured human lymphoid cell lines having different HL-A phenotypes. Cytotoxic antibodies reacting with these cultured cells were now detected in some of the sera. These antibodies were not directed against HL-A antigens, yet mediated lysis of target cells in the presence of rabbit but not of human or guinea pig complement. Furthermore, they activated the classical pathway of the rabbit complement system. Later, a significant association was found between occurrence of cytotoxic antibodies and rejection of the transplant. Thus, cultured human lymphoid cells, because of their great susceptibility to complement-mediated lysis, appear to be useful in detecting humoral sensitization in candidates for kidney grafts.

Antibody Formation↗