PubMed Health⌕ Search

Biomedical subjects

T Z Lin

Publications and source records attributed to T Z Lin.

10 recordsLinked to original sources
PubMed1992

IL-10 production in a CD5+ B cell lymphoma arising in a CD4 monoclonal antibody-treated SJL mouse.

A majority of SJL mice develop spontaneous reticulum cell sarcomas (RCS) at about 1 year of age which can be transplanted into young SJL recipients. Previous studies have shown that RCS tumors are of B cell lineage, and that the development of these lymphomas and their subsequent growth depends upon host-derived T helper cell factors. In vivo treatment of SJL mice with anti-CD4 monoclonal antibody (mAb) prevents the development of the characteristic B lymphomas. Most of the mAb-treated animals were tumor free and had a significantly prolonged life span. However, one such CD4 mAb-treated mouse developed a transplantable IgM+ CD5+ B cell lymphoma (designated NJ101), which has not previously been described in SJL/J mice. NJ101 is clonal on the basis of a discrete non-germ line Ig heavy chain gene rearrangement by Southern blot analysis. Unlike the sIg- CD5- transplantable RCS-X cell line, the IgM+ CD5+ NJ101 lymphoma cells will grow in immuno-compromised hosts, such as irradiated recipients or in recipients treated with CD4 mAb in vivo. The RCS (B cell) lymphoma requires CD4+ T cells for progressive growth, whereas the growth of the CD5+ B lymphoma cells is enhanced by the removal of such cells. Thus, CD5+ B cell clonal development may be aided by the removal of regulatory T cells and/or the malignant CD5+ B cells may produce their own growth factors in an autocrine manner. Examination of IL-10 message by quantitative polymerase chain reaction techniques indicate that the CD5+ B lymphoma cells produce increased levels of IL-10 relative to normal LN cells or purified RCS lymphoma cells. These results suggest that two different types of B cell tumors, both of which can develop in SJL mice, have different growth requirements. Furthermore, treatment to prevent the occurrence of the characteristic RCS malignancy of SJL mice may lead to the development of another form of B cell neoplasia.

Animals↗
PubMed1991

Syngeneic B lymphoma cells provide a unique stimulus to natural killer (NK) cells in genetically low-NK SJL/J mice.

SJL/J mice are a genetically low-NK strain, and their cytotoxic activity cannot be augmented with conventional NK inducers. In contrast, effector cells taken from the lymphoid tissues of SJL mice bearing a syngeneic B cell lymphoma (RCS) show variable, but significant levels of cytotoxic activity against NK-susceptible targets, such as YAC-1. Previous results suggested that the RCS cells themselves contributed to this cytotoxicity. However, results presented here indicate the most, if not all of the activity present within the lymphoid tissues of RCS-bearing mice is mediated by RCS-activated, host NK cells. These results were confirmed by in vitro studies, which demonstrate that both gamma irradiated (gamma-) RCS cells and gamma-allogeneic spleen cells induce cytotoxic activity in SJL spleen cells against YAC targets. However, the cytotoxicity induced by gamma-allogeneic cells is mediated largely by lymphokine-activated killer (LAK) cells, since these effectors also lyse NK-resistant target cells, such as L1210. In contrast, the cytotoxic effector cells that are induced by syngeneic gamma-RCS cells cause lysis of YAC targets, but not L1210 target cells. These data indicate that the syngeneic B cell lymphomas of SJL mice are a unique stimulus for host NK cells in this strain. Since activated NK cells produce a variety of lymphokines, RCS stimulation of host NK cells in SJL mice may provide some of the growth-promoting lymphokines that are known to be necessary for progressive growth of these lymphoma cells.

Animals↗
PubMed1991

Influence of host environment on growth of clonal CD5+B (Lyl+B) cells.

Autoimmune NZB mice have increased percentages of CD5+B (Lyl+B) cells in both the spleen and peritoneum. We have previously reported that as NZB mice age they develop a clonal population of hyperdiploid CD5+B cells in the spleen. These cells can readily be transplanted into unirradiated recipients. The growth characteristics of such transplanted hyperdiploid NZB spleen cells were examined in different recipient strains to determine if the immunological status of the host environments affected the growth of the clonal CD5+B cells. Young NZB and NZB.xid recipients (lacking hyperdiploid CD5+B cells) allowed growth and expansion of unpassaged CD5+B cells derived from primary NZB mice. Similarly, (NZBxDBA/2) and (NZBxBALB/c) F1 recipients allowed for expansion of CD5+B cell clones from primary sources. In a separate experiment, T cell-depleted NZB spleen cells containing a hyperdiploid CD5+B cell clone were transferred to SCID mice. The SCID environment supported the growth of the primary clone. None of these recipients normally have elevated CD5+B cells, yet these recipients allowed growth of primary transferred hyperdiploid cells. However, a difference in the ability of these recipient strains in their ability to expand multiply passaged CD5+B cell clones was observed. These results indicate that while hyperdiploid CD5+B cells are difficult to be maintained in culture, they can readily be passaged in vivo. The host environment may provide growth factors or signals for endogenous growth factors. Although the CD5+B clones arise initially in a hyperactive autoimmune environment, a hyperimmune environment is not necessary to support their growth. Transferred CD5+B cells affect the recipient environment and reduce the percentages of normal B cells.

Animals↗
PubMed1989

[Postero-anterior cephalometric features in Japanese children with malocclusion].

The purpose of this study is to investigate the craniofacial morphology and the growth pattern in the frontal dimension of Japanese children with malocclusion. Nine hundred twenty-one subjects composed of 343 males and 578 females without any orthodontic treatment, age ranging from 7 years to 18 years, were classified into 3 types of facial skeletal pattern according to the A-B difference in lateral cephalogram. The direct measurement of the width and the relative ratio of the craniofacial components to the cranium were used for the parameter of the craniofacial size and shape. The following results were obtained: 1. Independently of malocclusion, the craniofacial size of the male was significantly larger than that of the female, while the craniofacial shape of the male was almost same as that of the female. 2. In despite of the remarkable morphological difference in the lateral dimension, the characteristic morphology peculiar to a certain facial type could not be extracted in the frontal dimension. 3. In all types of malocclusion, a marked amount of growth was observed in the midface and mandible. However, the growth pattern of each craniofacial component in the female sample showed almost the same pattern, comparable with the different pattern of the midface and mandible in the male sample. 4. The clinical application of this study was tested in a case of Apert's syndrome.

Adolescent↗