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1.
Summary This paper reports the occurrence of an accumulation of lethally altered lymphocytes in the subcapsular sinus of a compartment or compartments of some lymph nodes, an unusual feature best developed in nodes of the mesenteric site in aging athymic animals. Many of these cells are rod-like. In other compartments, similar lymphocytes occurred at various depths in the nodal parenchyma. This was accompanied by the disappearance of a compartment's populations of normal lymphoid cells. The observations reveal that lymphocytes, altered in a tissue, may reach the subcapsular sinus of the draining node compartment and migrate into its parenchyma which then undergoes atrophy. The likely involvement of mast cells is discussed.This work was funded by the Medical Research Council of Canada. 相似文献
2.
Freeze-fracture studies of the sinoatrial and atrioventricular nodes of the caprine heart,with special reference to the nexus 总被引:1,自引:0,他引:1
Summary The caprine sinoatrial node (SAN) and atrioventricular node (AVN) were studied by freeze-fracture techniques, and their nexus or gap junction structure were compared with that of ordinary atrial and ventricular muscle cells. The general features of the nexus in both the SAN and AVN were essentially identical. Approximately two-thirds of the nexuses observed in the nodal cells consisted of typical macular arrangements of nexal particles, and the remaining third, of atypical configurations of either circular arrangements or linear arrays of particles in continuity with the macular nexuses. Such atypical nexuses were never observed in the ordinary adult myocardial cells. Quantitative analysis revealed that all of the nexuses in the nodal cells measured, were less than 0.1 m2, whereas the majority of the nexuses in ordinary myocardial cells (64% in the atrium and 76% in the ventricle) were larger than 0.1 m2. No significant differences in diameter and center-to-center distance of nexal particle were found between the nodal cells and ordinary myocardial cells. 相似文献
3.
Summary The popliteal lymph nodes were removed from young rats of various ages five days after a single immunization with TNP-KLH in the hind footpads. Cryostat sections of the lymph nodes were investigated by means of enzyme and immunohistochemical techniques at the light-microscopical level.The presence and localization of anti-TNP antibody-containing cells were examined using a new technique to visualize specific antibodies. Moreover, the development of the lymph nodes following exogenous antigenic stimulation was compared with that of unstimulated lymph nodes.Specific antibody-containing cells could not be found before day 15 after birth, in rats immunized at day 10. From that time these lymphoid cells were located primarily at the border between cortex and medulla. Younger popliteal lymph nodes showed only aspecific immunoglobulin-containing lymphoid cells. With age, the number of specific antibody-containing cells tended to increase. These cells were more mature, according to morphological criteria and were located nearer the medulla.The first primary follicles were seen at day 19, as was the case in unstimulated animals. The first secondary follicles, containing germinal centers, were detected at day 23, whereas in unstimulated popliteal lymph nodes they were never found.Trapping of immune complexes could not be demonstrated before day 33 after birth. The later appearance of this phenomenon might be a consequence of the techniques applied to demonstrate specific antibody-containing cells.Abbreviations PLN
popliteal lymph node
- FDC
follicular dendritic cell
- IDC
interdigitating cell
- HEV
high endothelial venule
- TNP
trinitrophenyl
- KLH
keyhole limpet hemocyanin
- PBS
phosphate-buffered saline
- GCPC
germinal center precursor cell
-
sIg
surface immunoglobulin
-
cIg
cytoplasmic immunoglobulin 相似文献
4.
Lymphocyte subpopulations of regional lymph nodes in human colon and gastric adenocarcinomas 总被引:3,自引:0,他引:3
Beatriz Lores-Vazquez Margarita Pacheco-Carracedo Josefina Oliver-Morales Purificación Parada-Gonzalez F. Gambón-Deza 《Cancer immunology, immunotherapy : CII》1996,42(6):339-342
In order to study the host immune response to tumours, previous knowledge of the cellular composition of regional draining
lymph nodes is necessary. Enlarged regional lymph nodes are a common finding in colon and gastric adenocarcinomas. We have
studied the cellular composition of normal non-reactive and of regional draining lymph nodes of colon and gastric adenocarcinomas.
In normal non-reactive lymph nodes, T lymphocytes (CD2+, CD7+) constituted the largest fraction of the lymphoreticular cells. These lymphocytes were mainly CD4+, and there were more cells expressing the CD45RA isoform of the CD45 antigen than CD45RO. Reactive lymph nodes presented
a decreased proportion of CD4+ CD45RA+ cells and an increased number of B cells. Although most of the T cells in the reactive nodes were CD4+ CD45RO+, their proportion was similar to that found in normal non-reactive nodes. We studied the presence of the molecules CD28 and
CD80 involved in the processes of interaction and activation of T and B lymphocytes. The CD28 molecule was found in all the
T lymphocytes, while the CD80 molecule was weakly expressed on the B lymphocyte membrane.
Received: 4 January 1996 / Accepted: 28 May 1996 相似文献
5.
Effects of interleukin-12 on in vitro culture with interleukin-2 of regional lymph node lymphocytes from lung cancer patients 总被引:2,自引:0,他引:2
T. Hanagiri Mitsuhiro Takenoyama Takashi Yoshimatsu Chikashi Hirashima Ichiro Yoshino Kozo Nakanishi Akira Nagashima Kikuo Nomoto Kosei Yasumoto 《Cancer immunology, immunotherapy : CII》1996,43(2):87-93
In the present study, we carried out a functional analysis of regional lymph node lymphocytes (RLNL) from patients with lung
cancer after in vitro activation by interleukin-2 (IL-2) and interleukin-12 (IL-12). IL-12 (100 U/ml) enhanced both the proliferation
and cytotoxic activity of RLNL in a culture with low doses of IL-2 (5 – 10 JRU/ml). After comparing an RLNL culture with a
low dose of IL-2 alone, a higher proportion of CD8+ cells and CD56+ cells and a lower proportion of CD4+ cells were found in the culture with both IL-12 and a low dose of IL-2. Such a combination of the cytokines effectively activated
RLNL in terms of the expression of IL-2 receptors. In the culture condition of IL-12 and a low dose of IL-2, a synergistic
effect was observed in the production of such cytokines as interferon γ, tumor necrosis factor α (TNFα), and TNFβ, as well
as in tumor cytotoxicity. However, the addition of IL-12 inhibited the cytotoxicity of RLNL in the culture with a high dose
of IL-2 (100 JRU/ml). This inhibition is considered to be partially due to the endogenous production of TNFα by lymphocytes,
because the neutralization of TNFα bioactivity partially restored the cytotoxic activities of RLNL. Furthermore, in the presence
of hydrocortisone, IL-12 synergistically enhanced the cytotoxic activity of RLNL cultured with a high dose of IL-2. These
results provide useful information about the improvement of adoptive immunotherapy against cancer using RLNL.
Received: 2 February 1996 / Accepted: 30 July 1996 相似文献
6.
Summary Chickpea was micropropagated by axillary shoot proliferation (ASP) and modified single node culture (MSNC) methods. Maximum
propagule proliferation occurred on Murashige and Skoog (MS) medium enriched with 1–10 μM N6-benzyladenine and 0.01 μM α-naphthaleneacetic acid. The propagules were rooted on MS medium containing 1 μM 3-indolebutyric acid and B5 vitamins. Regenerated plants were fertile and phenotypically similar to control plants grown from seed. The MSNC method was
four times more efficient than the ASP method in terms of the number of plants produced per explant. 相似文献
7.
The sequences of the internal transcribed spacer (ITS) region of 18S–26S nrDNA for a sample of 16 taxa from theInuleae s. str. and two outgroup taxa are analysed cladistically with PAUP. A consensus tree of the four most parsimonious cladograms is presented. Three different tests of cladogram stability are conducted (Bremer support, parsimony jackknifing and bootstrapping); all tests indicate a high degree of support for the basal nodes of the tree. The ITS phylogeny of the tribe is compared with previous hypotheses based on morphological data. The position ofAnisopappus as sister group to the rest of the tribe is supported by the molecular data, but the proposed subdivision ofInuleae s. str. into a paleate grade group and an epaleate clade is not. The interpretation of the character evolution of, e.g. receptacular paleae and pappus features within the tribe is discussed. 相似文献
8.
CD4+8– T lymphocytes with potent antitumor activity in vivo were obtained in peritoneal exudate cells by immunizing mice with irradiated MM48 tumor cells admixed with OK-432. These immune CD4+ T cells were used in adoptive immunotherapy for prevention of lymph node metastases after removal of the primary tumor. Complete cure of metastases was obtained by adoptive transfer of CD4+ T cells admixed with irradiated MM48 tumor cells, but not by CD4+ T cells alone. To analyze the curative effect of admixing tumor cells on the prevention of metastases, a model of 1-day tumor inoculated with macrophages was used. Administration of immune CD4+ T cells alone resulted in the regression of local tumor in more than half of the mice, although all of them eventually died of lymph node metastases. On the other hand, adoptive transfer of immune CD4+ T cells plus irradiated tumor cells resulted in the complete regression of local tumors in all the mice, which survived without any sign of metastasis. The curative effect of the immune CD4+ T cells obtained by admixing irradiated tumor cells was tumor-specific. Macrophages induced by OK-432 (tumoricidal), implanted together with tumor, assisted tumor regression more than did macrophages elicited by proteose peptone (nontumoricidal) in the same adoptive transfer system. Administration of recombinant interleukin-2 instead of stimulant tumor cells did not enhance, but rather eliminated the constitutive antitumor activity of CD4+ T cells. On the other hand, exogenous recombinant interleukin-1 was more effective in the enhancement of antitumor activity of the CD4+ T cells as compared with stimulant tumor cell administration. In this case, the activating states of macrophages at the implanted tumor site had no influence on the therapeutic efficacy. A possible role of macrophages for induction of tumor-specific cytotoxic T cells that were mediated by tumor-specific CD4+ T cells is discussed. 相似文献
9.
The murine local lymph node assay is a novel predictive test for the identification of skin sensitizing chemicals. The method measures sensitization potential of a chemical in mice as a function of proliferative activity induced in lymph nodes draining the site of topical exposure to that test chemical. Here we describe the use of the local lymph node assay for evaluation of the relative potency of skin sensitizing chemicals via derivation of the concentration required to produce a threshold positive reaction. Subsequently, the development of risk assessments based on comparisons with index contact allergens is outlined. 相似文献
10.
摘要 目的:研究乳腺癌患者新辅助化疗(NAC)后达到腋窝淋巴结病理完全缓解(pathologic complete response of axillary,apCR)的远期生存以及影响远期生存的相关因素分析。方法:回顾性分析哈尔滨医科大学附属肿瘤医院乳腺外科624例乳腺癌患者的住院资料,采用Kaplan-Meier生存分析以及COX回归分析的统计学分析方法,分析乳腺癌患者新辅助化疗后腋窝状态与无病生存(DFS)和总生存(OS)的关系及影响apCR预后的因素。结果:apCR与非apCR患者比较DFS(P=0.013)和OS(P=0.037)差异具有统计学意义,apCR患者的预后与年龄、肿瘤大小、肿瘤受体状态、HER-2、ki67状态、分子分型等因素无相关性。结论:与非apCR患者相比,乳腺癌患者新辅助化疗后apCR患者预后更好,但apCR患者预后良好的因素仍需进一步临床试验分析。 相似文献