Search PubMed⌕ Search

Biomedical subjects

B Kelly

Publications and source records attributed to B Kelly.

At least 145 records · Page 8Linked to original sources
PubMed1979

Isolation and partial characterization of immunologically reactive fractions from chitinase digested cell wall of Trichophyton mentagrophytes.

Cell wall preparations of Trichophyton mentagrophytes were digested with chitinase following which various fractions were isolated by ultrafiltration and Sephadex gel filtration. All fractions isolated contained both polysaccharide and peptide material. A correlation was seen between those fractions capable of eliciting immediate and delayed skin reactions in sensitized guinea pigs and those capable of stimulating the in vitro proliferation of lymphocytes taken from sensitized guinea pigs. These immunologically active fractions also developed precipitin lines with antiserum taken from sensitized animals. A low molecular weight fraction was found to be completely reactive immunologically (UM2(a)), and appeared to have a molecular weight in the range of 2,000--4,000 as assessed by ultrafiltration and gel filtration studies.

Animals↗
PubMed1979

Characterization of immunologically active peptides from the cell wall of T. mentagrophytes.

A low molecular weight fraction from chitinase digested cell walls of T. mentagrophytes containing both polysaccharide and peptide moieties was found to have immunological reactivity at both the cellular and humoral level. This fraction (UM2(a)) was further degraded by treatment with either a combination of pronase and carboxypeptidase A or with trypsin. Peptides were separated from the carbohydrate-rich fraction by ultrafiltration. The carbohydrate-rich fraction retained the ability to induce both immediate and delayed skin reactions in sensitized guinea pigs and to stimulate the proliferation of sensitized lymphocytes in vitro. The peptide moieties retained reactivity in that they caused delayed reactions and lymphocyte proliferation but were unable to induce immediate or Arthus reactions in sensitized animals. Tryptic peptides from UM2(a) were purified by ion exchange chromatography. A high proportion of these peptides demonstrated immunological activity at both the cellular and humoral level since they were capable of inducing delayed reactions and/or lymphocyte transformation, as well as being capable of blocking the complement fixation reaction between UM2(a) and specific antiserum.

Animals↗
PubMed1977

Evidence for a common tumour-associated antigen in extracts of human bronchogenic carcinoma.

Xeno-antiserum specific for antigenic components of bronchogenic carcinoma was raised in rabbits, by passively immunizing them to normal human lung antigens at the same time as immunization with a tumour extract from a squamous-cell carcinoma. Antiserum so raised contained minimal quantities of anti-normal antibody which could be removed by a single absorption with glutaral-dehyde-insolubilized normal lung extract. When tested by quantitative complement fixation with a panel of tumour extracts from surgical specimens, it was found that the antiserum gave positive complement fixation with all squamous-cell carcinoma extracts tested, and with some of the extracts from bronchogenic carcinomas of differing pathological types. The antiserum was essentially negative for pooled extracts from normal lung, liver and spleen but gave a weak positive reaction with an extract of pooled foetal lung tissue.

Antibodies, Neoplasm↗
PubMed1977

Identity of a T-lymphocyte inhibitor with mouse immunoglobulin in the serum of tumour-bearing mice.

A component of the serum of tumour-bearing mice has been shown to be inhibitory to the immunological function of normal mouse T cells. This factor fractionates with monomeric immunoglobulin upon gel filtration. Studies were carried out utilizing goat antisera to the major immunoglobulin chains of mouse Ig (kappa, gamma, alpha and mu) mixed with the immunoglobulin-rich fraction of serum from normal mice and tumour bearers and passed through immunoadsorbent columns prepared with rabbit anti-goat immunoglobulin. Such studies showed that the inhibitory activity in tumour-bearing serum could be removed after treatment with anti-kappa, anti-gamma and anti-mu chain antisera but not by treatment with either anti-alpha chain or goat immunoglobulin. That the inhibitory activity of tumour-bearing immunoglobulin could be attributed to simple quantitative differences in the levels of IgM and IgG in the test samples was discounted by quantification of the amounts of immunoglobulins in normal and tumour-bearing sera.

Animals↗
PubMed1976

The immune response to oxidized ferredoxin. II. Cross reactivity of cells and antisera to modified ferredoxins and the nature of the cells responding in vitro.

The cross reactivity of sera from rabbits sensitized to performic acid oxidized ferredoxin (O-Fd) and of spleen cells from mice sensitized to O-Fd was analysed using several chemically modified forms of ferredoxin in the complement fixation test and the in vitro lymphocyte stimulation assay. Only O-Fd and native ferredoxin (native-Fd) gave positive responses in both assays. Dinitrophenylated-O-Fd (DNP-O-Fd) and acid precipitated ferredoxin (TCA-Fd) were able to fix complement (C') but did not simulate DNA synthesis in vitro. Ferredoxin alkylated with N-ethylmaleimioxin (CM-Fd) was unable to stimulate DNA synthesis and was marginally able to fix C'. Methylated-O-Fd (meth-O-Fd) was not recognized in either assay. The various ferredoxin preparations were tested for their ability to sensitize mice for use in the in vitro lymphocyte stimulation assay. Only O-Fd, NEM-Fd and native-Fd were capable of sensitizing lymphocytes for a proliferative response in vitro to the test antigens. This correlates with the observation that only these antigens were able to induce DNA synthesis in O-Fd-sensitized lymphocytes. The nature of the cells responding in vitro was examined by treating the cells with rabbit anti-mouse immunoglobulin and C' or rabbit anti-mouse brain associated theta and C'. The 24-hr response was found to be sensitive to both sera while the 120-hr response was sensitive only to the anti-theta sera.

Alkylation↗
PubMed1976

The immune response to oxidized ferredoxin. I. Specificity of the response to the amino terminal determinant.

Several synthetic peptide analogues of the amino terminal antigenic determinant (ala-tyr-lysile-ala-asp-ser) of oxidized ferredoxin (O-Fd) were tested for their ability to inhibit the complement fixation reaction between O-Fd and homologous rabbit antiserum, and to inhibit the migration of spleen cells from guinea-pigs immunized to O-Fd or to a conjugate of the amino terminal heptapeptide (N7) and bovine serum albumin (N7-BSA). The results of the migration inhibition assay suggest that the tetrapeptide and longer peptides of the native sequence were all recognized and stimulated the production of migration inhibition factor. Peptides modified at the aspartic residue were partially active while the serine modified peptide was not. Modification at the amino end of the heptapeptide had no effect on migration inhibition. As specificity controls, it was shown that the N7-BSA conjugate inhibited migration in O-Fd immunized animals, while O-Fd inhibited migration in N7-BSA immunized animals. The hexa-, hepta-, aspartic-deleted and serine-modified peptides were able to inhibit the complement fixation reaction with O-Fd and specific rabbit antiserum. Inhibition found with the serine-modified peptide and the lack of inhibition with the amino-modified peptide or the di-, tri-, tetra- and pentapeptides indicates the determinant recognized by the rabbit antibodies is either larger or is located nearer the middle of the heptapeptide than the determinant which induced the production of MIF.

Amino Acid Sequence↗
PubMed1975

Responses of guinea-pig lymphocytes to mitogens, an antigen, and mixed leucocyte culture in media with and without mercaptoethanol and foetal calf serum.

The ability of guinea-pig spleen and lymph node cells to undergo a proliferative response in vitro in the presence of mitogens (concanavalin A and lipopolysaccharide), a specific antigen (oxidized ferredoxin), and allogeneic cells was assessed under a variety of conditions. Time and dose dependency of the responses was measured in RPMI 1640, RPMI 1640 plus mercaptoethanol (ME), RPMI 1640 plus foetal calf serum (FCS), and RPMI 1640 with ME and FCS. Mitogen responses were also measured after treatment of the cells with sheep antiguinea pig immunoglobulin (SaGPIg) and complement (C') or after passage through nylon wool columns. Lipopolysaccharide (LPS) stimulated the cells under all media conditions over a wide range of concentrations but over a narrow time period. Nylon wool treatment of the cells eliminated the LPS response while SaGPIg and C' reduced it. Concanavalin A (con A) stimulated the cells under all test conditions and demonstrated a dose-time interrelationship in terms of maximum response. Pre-treatment of cells with SaGPIg and C' enhanced the response to con A while nylon wool fractionation diminished it somewhat. Only lymph node cells responded in vitro to oxidized ferredoxin (OFd). In serum-free media the OFd responses were maximal at 48 hours whereas in media containing FCS proliferative responses were supported for a prolonged period and appeared to be bimodal. Except for an early response with RPMI 1640 and ME, only media containing FCS supported stimulation in the mixed leucocyte culture.

Animals↗
PubMed1975

Cellular co-operation by mouse lymphocytes to chemically defined antigens.

When populations of mouse spleen cells were treated with a highly radioactive 125I-labelled haptenic conjugate (125I-labelled PDG-N) and subsequently injected into X-irradiated, immunized (N-10-C) syngeneic BALB/c mice, it was found that after autoradiography with 125I-labelled N and C haptenic conjugates, the numbers of ABC to both the N and C haptens decreased. The number of ABC found were significantly lower than those found in mice that had been reconstituted with cells "suicided" with another 125I-labelled antigen (125I-labelled BSA) and subsequently immunized with N-10-C.

Animals↗