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W Zhong

Publications and source records attributed to W Zhong.

137 records · Page 8Linked to original sources
PubMed1991

[Preparation of SOKT1-RTA immunotoxin and its specific cytotoxic effect on human T lymphocytes].

An immunotoxin, SOKT1-RTA, was prepared successfully by conjugating a murine anti-human T lymphocyte monoclonal antibody (McAb) SOKT1 and the ricin toxin A chain (RTA) with the heterobifunctional linker SPDP. At the presence of 20 mmol/L NH4Cl, the SOKT1-RTA conjugate killed 82% of the human peripheral blood T cells (PBT), and decreased their 3H-Leu incorporation to 6.2% of the untreated controls. The toxic effect of the immunotoxin can be partially blocked by unconjugated SOKT1, but not by an irrelevant McAb D51. These results indicated that the SOKT1-RTA conjugate still retains both functions of its component parts:binding to human PBT specifically, and inhibiting protein synthesis. It may be an effective reagent for in vitro depletion of immunocompetent T cells from human bone marrows.

Antibodies, Monoclonal↗
PubMed1991

[Influences of an anti-pan-T cell ricin A-chain immunotoxin on generation of human immunocompetent T cells and hematopoietic progenitor cells].

SOKT1 -RTA immunotoxin, which consisted of an anti-pan-T cell monoclonal antibody SOKT1 and ricin toxin A-chain, decreased the peripheral blood lymphocyte transformation in response to PHA and to alloantigen by 92.9% and 84.7%, respectively. The generation of allocytotoxic T cell was also dramatically inhibited by this immunotoxin. After treatment of human bone marrow mononuclear cells with the immunotoxin, erythroid proliferation in CFU-E test preserved 62.9%. Based on these findings, we concluded that SOKT1-RTA immunotoxin can effectively inactivate human T lymphocytes in vitro without serious toxic effect on the hematopoietic progenitor cells. It may be an effective agent in aGVHD prophylaxis.

Antibodies, Monoclonal↗
PubMed1989

Axonal signals regulate expression of glia maturation factor-beta in Schwann cells: an immunohistochemical study of injured sciatic nerves and cultured Schwann cells.

Glia maturation factor-beta (GMF-beta) is a 17 kDa protein purified and sequenced from bovine brains. Using the monoclonal antibody G2-09 directed against GMF-beta, we previously demonstrated endogenous GMF-beta in astroblasts, Schwann cells, and their tumors in culture. In the present study, we have used indirect immunofluorescence microscopy with G2-09 to examine the effects of transection, crush, and regeneration of sciatic nerve on the expression of GMF-beta in Schwann cells in situ and to study the time course of GMF-beta induction in Schwann cells in vitro. For comparison, a parallel study was carried out with monoclonal antibodies directed against nerve growth factor (NGF) receptor. We found that (1) neither GMF-beta nor NGF receptor was detectable in intact sciatic nerves, (2) all Schwann cells of the distal segment of the transected nerve expressed GMF-beta as early as 3 d after axotomy that persisted up to 3 weeks, (3) axonal regeneration repressed the Schwann cell expression of GMF-beta, (4) isolated Schwann cells derived from rat sciatic and adult human sural nerves developed intracellular GMF-beta in culture following an initial lag period, and (5) the induction of Schwann cell NGF receptor coincided temporally with that of GMF-beta in the transected nerve and in culture. These results show that the expression of GMF-beta in Schwann cells, as is the case with the NGF receptor, is induced by the loss of the normal axon-Schwann cell contact. We propose that the induction of GMF-beta, as well as NGF receptor, in Schwann cells after nerve injury plays a role in axonal regeneration.

Animals↗
PubMed1988

[Luteinizing hormone-releasing hormone (LRH) agonist in the treatment of breast cancer, osteosarcoma and prostate carcinoma--analysis of 12 patients].

This paper first reports the results of 12 patients with sex hormone-dependent neoplasms, including 9 women with breast cancer, 2 men with osteosarcoma and 1 man with prostate carcinoma, treated by LRH agonist, (D-Ala6, des-Gly-NH2(10))-LRH-ethylamide (LRH-A) 100-200 micrograms, IM, QD. After 15-30 days of administration, the concentrations of plasma mean estradiol, progesterone, testosterone, serum luteinizing hormone and follicle-stimulating hormone were lowered significantly in the peripheral blood of all patients, associating with improvement of the patients' general condition and reduction of the tumors and/or metastatic foci. No serious side effects were observed except vaginal irregular bleeding in isolated patients. Three patients died and the others were alive in follow-up of 4-30 months. The results suggest that LRH-A be useful in the treatment of the sex hormone-dependent tumors and worth further study.

Adolescent↗
PubMedDate not supplied

Relationship between the Borrelia burgdorferi specific immune response and different stages and syndromes in neuroborreliosis.

One hundred untreated neuroborreliosis patients were investigated by IgG/IgM immunoblot to find out if different stages and syndromes are characterized by different patterns of their Borrelia burgdorferi specific immune responses in CSF and serum. Stage III (n = 10) was characterized by a broad, highly specific intrathecal immune response (the mean number of IgM bands in CSF was 3.1 and of IgG bands 6.3). All patients recognized one or more of the following proteins (p35, p21, p18) or the 5 kd glycolipid. In contrast, the immune response in stage II (n = 90) was less restricted (28%) and heterogeneous (mean number of IgM bands 1.4 and of IgG bands 3.4). It was mainly directed against the highly crossreactive p41 antigen (91%). The different clinical features of stage II were comparable regarding the intrathecal immune response. However anti-glycolipid and anti-p35, -p21, -p18 IgG antibodies were detected in a small subset of patients, mainly corresponding to more severe courses of the disease. Our data are compatible with a direct agent-related pathomechanism in neuroborreliosis. Antibodies against certain proteins and the glycolipid of B. burgdorferi seem to have a prognostic value as to the development of more severe disease or transition to stage III.

Adolescent↗
PubMedDate not supplied

New flexible growth function and its application to the growth of small mammals.

The function [formula: see text] where a is the upper asympotic weight and b, c, k are constants, is derived as a new flexible growth equation and evaluated using commonly applied growth functions such as Monomelecular, Gompertz, Logistic, Richards, France, Janoschek and Hill. Three sets of observations on growth of small mammal species (Microtus brandti and Ochotona curzoniae) are used to evaluate the fits of these functions. In addition, points of inflexion of these growth equations are also derived in this paper. The new function encompasses the Logistic and Monomolecular equation for different value of parameter b. It provides a flexible growth equation capable of describing smooth sigmoidal and diminishing returns behaviour. The success of the new equation in describing these sets of growth patterns underlines its credentials as a suitable additional growth function.

Aging↗