Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.10.2 (focal adhesion kinase)
 44,029 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The immune capabilities of the Peyer's patches have been investigated by the use of an in vitro system. Despite our failure to stimulate Peyer's patch lymphocytes in vivo it appears that Peyer's patches behave immunologically as peripheral lymphoid tissues. Cultures prepared from the dissociated Peyer's patches of normal rabbits respond to sheep erythrocytes. The response is comparable to that obtained with spleen cultures from the same animals and is not dependent on the presence of the epithelial cells which line the lumen. Similar thymic cultures do not respond. Our experiments with cultures prepared from rabbits which have received one or two injections of SRC show that the Peyer's patches contain both IgM and IgG "memory" cells which have migrated from the spleen. The concentration of these cells in the spleen remains several hundredfold higher.
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PMID:Peyer's patches: immunologic studies. 546 17

The effect of high specific activity thymidme-(3)H on proliferation and antibody production, using the hemolytic plaque-forming technique, by spleen cell suspensions in vitro from rabbits killed after a boost of SRC's has been studied. High specific activity thymidine-(3)H inhibited the proliferative ay well as the antibody response to antigen, and it was conduded that this was the result of the incorporation of radioactive (3)H into the nuclei of dividing cells which were synthesizing antibody in these cultures. The stimulation of the rate of DNA synthesis by specific antigen could be correlated with the ability of antigen to maintain antibody production, as measured by the specific hemolytic plaque-forming technique, above levels found in control cultures, incubated without antigen. Radioautographic studies of PFC's in vitro showed that the majority of the cells arose from the DNA-synthesizing population of cells in these cultures, confirming the conclusions from the results of the inhibitory effects of high specific-activity thymidine-(3)H on PFC's. It was found that these PFC's, labeling with thymidine-(14)C, formed only a small proportion of all the cells labeled in this way in these cultures. The postulation was made that antigen, in vitro, provided a stimulation for cell proliferation in the responsive population of rabbit spleen cells, but that only a small proportion of this population could be induced by antigen to synthesize antibody.
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PMID:Antibody production in vitro. I. Single cell studies of the secondary response to sheep erythrocytes. 564 63

The effects of actinomycin D and puromycin on spleen cell suspensions from rabbits immunized to SRC's were studied. These inhibitors, in high concentration, suppressed PFC's when added initially to recently isolated cells. When such cells were incubated for several days in the presence of both antigen and inhibitor, both actinomycin D and puromycin produced an increase in PFC's after the initial suppression. This recovery effect was best seen with cells from rabbits killed 3 days after boosting with SRC's, and was usually absent when cells were taken from rabbits killed 2 days after boosting. When actinomycin D or puromycin was added after several days in culture in the presence of SRC's, surviving PFC's were found to be not only resistant to these inhibitors, but there was also an increased number of PFC's compared to similar cultures incubated without these agents. Radioautographic studies showed that PFC's stimulated by the presence of actinomycin D or puromycin were not incorporating precursors for RNA or protein synthesis. In view of the known mode of action of these inhibitors, it was postulated that they were stimulating antibody production by PFC's in vitro either by interfering with represser mechanisms or stimulating the completion of antibody molecules, perhaps by causing the release of preformed antibody chains from ribosomes. Since the presence of specific antigens in vitro were necessary for these observed stimulatory effects on PFC's, and since antigens were producing an effect on antibody production on cells which were being suppressed by these inhibitors, added initially, it was further suggested that one role of antigen in the immune response was concerned with the completion of antibody synthesis on the ribosomes, perhaps by acting as an inducer as has been suggested previously (1).
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PMID:Antibody production in vitro. II. Effects of actinomycin D and puromycin on the secondary response to sheep erythrocytes. 564 64

With the aid of a specific rabbit antibody preparation to purified monoclonal murine IgE, two plaque-forming cell (PFC) assays have been developed for the detection and enumeration of mouse IgE-secreting cells. The first assay, utilizing protein A-coated sheep red cells (protein A-SRC), detected antibody-secreting cells on the basis of the class of the secreted Ig irrespective of antigen specificity. With this assay, 30% of the class of the viable cells of two distinct IgE-secreting hybridoma cell lines were scored as PFC. Under these conditions, plaques were not obtained with IgG1 or IgG2a-secreting hybridoma cells. The second PFC assay, which utilized SRC coated with ovalbumin (OA-SRC), enumerated cells secreting anti-OA IgE antibodies. Similar kinetic patterns were observed for the cellular (IgE PFC/spleen) and humoral (IgE serum levels) responses of (C57BL/6 x DBA/2)F1 mice following immunization with 10 micrograms of OA adsorbed to 1 mg of A1(OH)3. Thus, it is concluded that the reverse plaque assay detecting all IgE-secreting cells, as well as the antigen-specific IgE PFC assay, can be used for the quantitation of IgE responses at the cellular level.
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PMID:The enumeration of mouse IgE-secreting cells using plaque-forming cell assays. 616 50

CBA mice were immunized with sheep red blood cells (SRBC) to obtain immune spleen cells (ISc) which were used to suppressor cells. Administration of ISC to intact syngeneic recipients on the immunization day led to a more powerful suppression of the immune response as compared to that seen one day after antigen injection. Four days after immunization the animals' immune response was not liable to be suppressed. ISC extract possessed similar effects with respect to the immune response of normal spleen cells which were transplanted to the cyclophosphamide-treated recipients. The immune response of spleen cells from mice immunized with SRBC in a dose of 10(6) was less liable to be suppressed. Hyperimmune spleen cells from donors immunized with SRC in a dose of 10(9) were insensitive to ISC or to the extract. Experiments with the use of adoptive transfer of a mixture of immune and intact T- and B-cells have disclosed that B-cells from hyperimmune donors were resistant to suppression. Therefore, B-lymphocytes are the most probable target cells exposed to T-suppressors in the given system. The mechanism is discussed of the selective effect of T-suppressors on B-cells in the course of the immune response development during immunization with high doses of antigen.
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PMID:[Analysis of certain mechanisms of antigen-specific suppression of the immune response]. 617 Mar 64

Ionizing radiation inhibited the development of specific haemolysin-producing cells (PFC) and depressed the incorporation of (3H) thymidine by rabbit spleen explants responding to SRC in the culture medium. In contrast to these effects, the rates of incorporation of precursors for protein and RNA synthesis were much less affected. The depression of (3H) thymidine incorporation was found to result from a quantitative reduction of new DNA synthesis, without any change in the proportion of labelled cells, at any time after irradiation. The DNA synthesis occurring in these cells preparing to develop antibody-producing capacity was thus radio-sensitive, but the exact nature of the defect resulting from exposure to radiation requires further study.
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PMID:The acute effects of ionizing radiation on DNA synthesis and the development of antibody-producing cells. 617 68

A sensitive method for the quantitation of IgG on platelets had not been demonstrated until 1975, when Dixon, Rosse, and Ebbert described a quantitative antiglobulin consumption test useful in detecting platelet associated IgG (N Engl J Med 292:230, 1975). A modification of that technique has rendered the assay reproducible and removed the need for daily repetition of a standard IgG titration curve for quantitation. This modification utilizes 1-ethyl-3-3(dimethylaminopropyl)carbodiimide HCl (ECDI) (Sigma, E-7750), in place of chromic chloride, as a coupling agent for attaching IgG (Miles 64-145) to sheep cells (SRC), used as indicator cells. The ECDI consistently couples IgG to SRC and does not subject the SRC to sporadic spontaneous lysis, as does chromic chloride. This modification permits the detection of IgG on platelets (Direct Test), or in sera (Indirect Test) by incubation of a washed platelet pool with sera in vitro, and testing as in the Direct Test. Normal values of 0.01-1.56 and 0.14-1.6 femtograms (F) per platelet have been obtained for the Direct and Indirect Tests, respectively. In six cases of suspected ITP, values ranged 12.0-221.0 F and 2.9-37.6 F for the Direct and Indirect Tests, respectively. In conclusion, in disease states or other abnormal situations, quantities of IgG can be detected that are not usually present on the platelets of normal subjects.
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PMID:A quantitative determination for the detection of immunoglobulin (IgG) on the surface of platelets. 617 61

Thin-layer chromatography (TLC) was used to separate components in the basic and tar fractions of solvent refined coal (SRC-I) process solvent (PS) to obtain materials suitable for biological and chemical analysis. Those fractions eluted from TLC plates which were mutagenically active in the Ames/Salmonella assay were analyzed by gas chromatographic mass spectrometry (GCMS) for polycyclic azaarenes, polyaromatic primary amines (PAA) and carbazoles. In all materials tested, a strong correlation was observed between the concentration of PAAs in a given TLC region and the mutagenicity of that region in the Ames assay system. Conversely, azaarenes having 2--4 fused rings and carbazoles were present in both mutagenic and non-mutagenic TLC eluates. No PAAs were detected in mutagenically inactive TLC eluates. In comparison to the mutagenic tar fractions, the PS basic fraction contained relatively larger concentrations of 2- and 3-ringed components such as aminonaphthalenes and aminoanthracenes or aminophenanthrenes. The tar fractions, which were essentially devoid of aminonaphthalenes, had a higher average molecular weight and contained relatively higher concentrations of aminopyrenes.
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PMID:Relative concentrations of polyaromatic primary amines and azaarenes in mutagenically active nitrogen fractions from a coal liquid. 617 60

C57BL/6J nu/nu mice respond to the type 2 TI antigen DAGG-Ficoll, but not to the TD antigen SRC. A comparable difference can also be seen in vitro, but only at high spleen cell density and in the presence of selected batches of FBS. At low spleen cell density and in the absence of FBS, the DAGG-Ficoll-induced B cell response is strictly dependent on soluble helper factors or cloned specific helper T cells. The B cell response so induced requires that the T cell-depleted spleen cells be compatible in the I-A subregion of the H-2 complex. These helper factors, induced by antigen in an I-A-restricted T cell-macrophage interaction, provide helper for T cell-depleted spleen cells irrespective of their H-2 haplotype. Under conventional culture conditions, the stringent requirement for helper factors in the in vitro response to DAGG-Ficoll is obscured by FBS. In vitro culture of low numbers of spleen cells, in serum-free medium instead of FBS, provides a sensitive assay for helper factors. We have compared the helper activity for a B cell response to SRC or DAGG-Ficoll as provided by antigen-induced supernatants of various individual EA-specific T cell clones. There was a remarkable and consistent heterogeneity among individual T cell clones: their helper activity in the response to TI and TD antigens did not correlate, nor was there any correlation between helper activity and antigen-induced TCGF (interleukin 2) activity.
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PMID:T cell control of the antibody response to the T-independent antigen, DAGG-Ficoll. 617 69

A panel of monoclonal rat antibodies binding to mouse mu heavy chain were tested for their ability to inhibit the formation of antigen-specific plaques in the hemolytic plaque assay. Nine antibodies inhibited SRC-specific direct IgM plaques at high concentrations (greater than 20 micrograms/ml). In contrast to all others, however, one antibody inhibited these plaques at much lower concentrations (down to 0.4 microgram/ml) when added to the assay. This antibody also inhibited plaques formed by cells secreting antibodies against trinitrophenyl or phosphorylcholine determinants. IgG plaques with any of the above specificities were not inhibited. IgM secretion was unaffected by the monoclonal anti-mu antibody. Its inhibitory effect on plaque formation rather appears to be a consequence of its ability to inhibit complement dependent, IgM mediated lysis of erythrocytes. This monoclonal anti-IgM antibody therefore provides a convenient reagent to distinguish specific direct IgM plaques from indirect IgG plaques.
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PMID:A monoclonal antibody with specificity for murine mu heavy chain which inhibits the formation of antigen-specific direct IgM plaques. 618 65


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