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H Shan

Publications and source records attributed to H Shan.

8 recordsLinked to original sources
PubMed1992

Selective pathogenicity of murine rheumatoid factors of the cryoprecipitable IgG3 subclass.

To analyze the involvement of rheumatoid factors (RF) in the generation of cryoglobulins and the development of related tissue injuries, we have established a panel of anti-IgG2a RF mAbs derived from MRL/MpJ-lpr/lpr (MRL-lpr), C3H/HeJ-lpr/lpr, and 129/Sv mice. After injection of hybridoma cells to normal mice, all four IgG3 RF mAbs induced cryoglobulinemia, and various degrees of glomerulonephritis and skin leukocytoclastic vasculitis. In contrast, none of the RF mAbs of the other isotypes generated cryoglobulins or tissue lesions. Since the same observation was obtained with another panel of five clonally related anti-IgG2a RF mAbs of MRL-lpr origin with almost identical heavy and light chain variable (V) regions but five different isotypes, it seems unlikely that the absence of pathogenicity of non-IgG3 RF mAbs was due to differences in fine specificity or V framework regions. In addition, the analysis of serum RF in MRL-lpr mice has demonstrated that a majority of 4 month old MRL-lpr mice produced substantial amounts of IgG3 RF with cryoglobulin activity. Because the cryoglobulin activity is associated with the murine IgG3 heavy chain constant region, RF of this subclass may play a significant role in the development of autoimmune-related tissue injuries, especially in MRL-lpr mice.

Animals↗
PubMed1991

Ig H and L chain contributions to autoimmune specificities.

An Ig H chain expression vector has been constructed by using the V region of 3H9, an antibody that binds ssDNA, dsDNA, and cardiolipin. The H chain construct was transfected into six hybridoma cell lines expressing Ig L chains. All resulting H and L chain combinations had at least some affinity for ssDNA, whereas five also bound dsDNA to a similar degree as 3H9. The loss of dsDNA binding was correlated with a single amino acid difference between two V kappa 8 L chains. A further characteristic of 3H9, its immunofluorescent staining pattern, was shared by four of the recombinant antibodies, whereas its specificity for cardiolipin was shared with five. The transfections reported here show that a V kappa 3 L chain confers specificity for an RNA-associated epitope and that a V kappa 21E L chain prevents cardiolipin binding. These experiments suggest that the 3H9 H chain contributes essential determinants required for binding to DNA as well as cardiolipin but that L chains can modulate or prevent this binding. L chains may also expand the specificity of a recombinant antibody.

Amino Acid Sequence↗
PubMed1991

Hemodynamic response to BMI model PIAB catheter.

Using the BMI model PIAB catheter designed and produced by our laboratory, we carried out serial animal experiments to evaluate its hemodynamic effects in goats. The animal experiments and comparison tests indicated that BAPDP = 24, PSP = 22; BAEDP = 8, EDP = 14; BAPSP = 20, PSP = 22. The various hemodynamic parameters of our PIAB catheter are equivalent to or better than those of imported products. But the price of our PIAB catheter is much lower than that of foreign products. It has been used in some hospitals, showing satisfactory results.

Animals↗
PubMed1990

Heavy-chain class switch does not terminate somatic mutation.

We studied the H-chain class switch rearrangement in four groups of clonally related B cell hybridomas, to test the hypothesis that class switch terminates somatic mutation in a B cell. Using switch region-specific probes in Southern blot analysis individual mu-gamma switch rearrangement events can be distinguished. We show that clonally related IgG-producing hybridomas that differ by mutations often share a common switch rearrangement. This indicates that class switch in these cells did not terminate somatic mutation.

Animals↗
PubMed1990

Anti-DNA antibodies from autoimmune mice arise by clonal expansion and somatic mutation.

The proximate cause of autoantibodies characteristic of systemic autoimmune diseases has been controversial. One hypothesis is that autoantibodies are the result of polyclonal nonspecific B cell activation. Alternatively, autoantibodies could be the result of antigen-driven B cell activation, as observed in secondary immune responses. We have approached this question by studying monoclonal anti-DNA autoantibodies derived from unmanipulated spleen cells of the autoimmune MRL/lpr mouse strain. This analysis shows that anti-DNAs, like rheumatoid factors (19), are the result of specific antigen-driven stimulation. In addition, correlation of sequences with fine specificity shows that: (a) somatic mutations can cause specificity for dsDNA and that such mutations are selected for; (b) arginine residues play an important role in determining specificity; and (c) anti-idiotypes that recognize the majority of anti-DNA are probably not specific for any one family of V regions.

Amino Acid Sequence↗
PubMed1990

[The anti-hemorrhagic shock of acupuncture on neiguan and its effect on the cardial pump function and the blood viscosity].

The purpose of this paper is to study and analyse the effects of the cardial pump function and the blood viscosity on rabbits with hemorrhagic shock by puncturing Neiguan. In the experiment 30 rabbits were divided into the electroacupuncture (EA) group and the control group, each group was 15 rabbits. The cardial pump function, the blood pressure and the blood viscosity were recorded during normalize, shock, and EA. The results were as following. 1. The blood pressure of the rabbits which were in hemorrhagic shock was raised by needling Neiguan. MAP was raised from 43 +/- 8 to 87 +/- 15 mmHg (p less than 0.001). 2. The cardial pump function were reinforced by needling Neiguan. SV was increased from 0.41 +/- 0.46 (before EA) to 0.73 +/- 0.12 ml (p less than 0.0001). CO, SI, CI. and WL were improved in a certain degree with difference significant. In the EA group the each index of the cardial pump function was higher than that of the control group. There was statistical significant between the two groups. 3. Needling Neiguan, the blood viscosity was tending to normality. The blood plasma viscosity was increased. There was significant difference (p less than 0.05). These results suggest that needling Neiguan may protect the cardial pump function, raise the blood pressure, play a positive role during anti hemorrhagic shock.

Acupuncture Points↗
PubMed1988

Biological characterization of a simian immunodeficiency virus-like retrovirus (HTLV-IV): evidence for CD4-associated molecules required for infection.

We have analyzed a number of biological features of HTLV-IV, a retrovirus indistinguishable from a macaque isolate of simian immunodeficiency virus (SIV), and compared this virus with several strains of human immunodeficiency virus type 1 (HIV-1). Although HTLV-IV was found to be similar to HIV-1 in its tropism for CD4+ lymphocytes, its effects on CD4 expression and the ability of its externalized envelope molecule to form a complex directly with the CD4 molecule, a number of striking differences were noted. Unlike with HIV-1, the range of cells susceptible to HTLV-IV infection and syncytia formation was restricted to a subset of CD4+ cell lines, particularly those that coexpressed CD4 with human leukocyte antigen (HLA) class II antigens. An analysis of the patterns of HTLV-IV infection with B x T somatic cell hybrids indicated that for this virus, molecules in addition to CD4 were probably required to facilitate infection and cell fusion. Additional studies of HTLV-IV infection of Sup-T1 cells, which are exquisitely sensitive to cytopathic effects induced by HIV-1, demonstrated that HTLV-IV infection could occur in the absence of cytopathic effects and, remarkably, with minimal or no downmodulation of the CD4 molecule from the cell surface. The failure of HTLV-IV infection to reduce the expression of several CD4 epitopes suggested that the HTLV-IV envelope produced by Sup-T1 cells was altered in its ability to interact with or bind to CD4. Additional differences were also noted in the size of the transmembrane envelope molecule of HTLV-IV produced by Sup-T1 cells, indicating that cell-specific alterations in processing of the HTLV-IV envelope occurred during the production of virus in this cell line. Understanding the basis for these biological differences between HTLV-IV and the HIV-1 viruses may help to elucidate more general mechanisms for pathogenesis of other members of the SIV and HIV families of retroviruses.

Animals↗