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O MAKELA

Publications and source records attributed to O MAKELA.

At least 19 recordsLinked to original sources
PubMed1975

p-Azobenzenearsonate-L-tyrosine-mediated helper function in immune responses of guinea pigs and rats.

A small bifunctional antigen (4-hydroxy-5-iodo-3-nitrophenyl)acetyl-epsilon-aminocaproyl-L-tyrosine-azobenzene-p-arsonate [NIP-cap-TYR(ABA)] was found to induce fair humoral antibody formation against NIP-cap but very little anti-ABA-TYR. This was observed in rats and guinea pigs. Prior immunization with ABA-TYR, either as such or coupled to dodecanoylated bovine serum albumin (lipid-BSA), primed rats for an enhanced anti-NIP response to NIP-cap-TYR(ABA). An attempt to encourage rats to produce anti-ABA-TYR in response to the bifunctional antigen by priming them with NIP-cap-lipid-BSA failed. Priming with ABA-TYR was dose-dependent. An injection of 1.5-15 nanomoles per rat primed for an increased production of anti-NIP while 150 nanomoles did not. Adult thymectomized x-irradiated rats had a poor anti-NIP response to the bifunctional antigen if they were reconstituted with T-enriched lymphoid cells from control mice, but a good response if reconstituted with similar cells from ABA-TYR-primed syngeneic rats.

Animals↗
PubMed1962

Autoradiographic studies on the immune response.I. The kinetics of plasma cell proliferation.

The origin and growth kinetics of plasma cells have been investigated using autoradiographic labeling techniques. Rats immunized once with Salmonella flagella were given a single pulse of H(3)-thymidine 4 or 40 weeks later. 2 hours after the tracer injection, they received a secondary antigenic stimulus. When animals were sacrificed immediately only certain cells from the resting primarily immunized lymph nodes, notably large and medium lymphocytes, were labeled. Subsequent to secondary stimulation, animals were killed at intervals; nearly all the plasma cells formed within the next 5 to 6 days were labeled. They must thus have been the progeny of cells already capable of synthesizing DNA in resting nodes, most probably of large lymphocytes. Plasmacytopoiesis began with little or no lag following secondary immunization, and the number of labeled plasma cells rose exponentially between the 2nd and 4th day, with a doubling time of about 12 hours. Studies of mean grain counts of primitive cells also suggested that the generation time of plasmablasts was 12 hours or less. The hypothesis was proposed that immunological memory depended on the persistence, following primary stimulation, of a continuously dividing stem line of primitive lymphocytes, reactive at all times to further antigenic stimulation.

Animals↗
PubMed1962

Autoradiographic studies on the immune response. II. DNA synthesis amongst single antibody-producing cells.

The DNA-synthesizing capacity of single antibody-forming cells was tested by a combination of micromanipulatory and autoradiographic techniques. Rats were immunized with S. adelaide flagellin, a protein antigen known to contain significant contamination with somatic (O) antigen. Single cells from secondarily immunized rats were tested for production of anti-H and anti-O antibodies by previously described and newer techniques. Positive antibody producers were transferred onto clean dry slides by micromanipulation, and autoradiographs were performed. When rats had received tritiated thymidine 1 hour before killing, labeling of antibody-forming cells was taken to imply that the cell was preparing for further mitotic division. It was found that on the 2nd and 3rd day of a secondary response, many of the antibody-producing cells in the nodes (chiefly plasmablasts) were incorporating tritiated thymidine. At the height of the cellular response, however, at 4 and 5 days, the majority of active antibody producers (chiefly mature plasma cells) were incapable of DNA synthesis. There appeared to be an inverse relationship between the antibody-forming and DNA-synthesizing capacities of the cell population under study; as more of the cells studied formed detectable antibody, fewer of them incorporated the DNA precursor. The age of plasma cells was also studied. Animals were killed at the height of the cellular immune response, having previously received an injection of tritiated thymidine 1 to 48 hours before killing; i.e., at 63 to 110 hours after their secondary stimulus. As the interval between isotope injection and killing increased, the proportion of antibody-forming cells showing labeling increased. With an interval of 30 hours, about half the antibody-forming cells were labeled and of 48 hours, over 95 per cent were labeled. This was taken as evidence that, few, if any, antibody-forming cells found at the height of a secondary response were more than 48 hours old. On the basis of these experiments and those reported in the accompanying paper, a simplified scheme showing the development of an antibody-forming clone in the secondary response was proposed.

Animals↗