Adoptive transfer of cell-mediated immunity to tuberculin using RNA from tuberculin-sensitive subjects.

Adoptive transfer of delayed hypersensitivity skin test response to tuberculin with 'immune' RNA extracted from the sensitized lymphocytes of a healthy subject or a patient with Hodgkin's disease was successfully demonstrated in previously non-sensitive patients with neoplastic diseases including Hodgkin's disease. 'Non-immune' RNA obtained from non-sensitive man, on the other hand, failed to transfer PPD skin reactivity in non-sensitive recipients. 'Immune' RNA-mediated PPD skin test response remained positive for a considerable period of time, indicating that the effect of 'immune' RNA is systemically active.

In vitro preferential effect of irradiation on cultured T lymphoid cell line.

The present report describes a comparative study of cytocidal effect of irradiation on human cultured T and B lymphoid cells. Cytocidal effect of irradiation was expressed as percentage inhibition or percentage reduction, which was calculated by comparing the [H]thymidine incorporations or viable cell counts in irradiated and unirradiated cultures, respectively. A higher percentage inhibition was observed in each and every T-cell culture, irradiated with 100–4000 rads at days 1–4 of incubation.

Synergism of stimulating capacity of pooled lymphocytes in the mixed lymphocyte reaction.

One-way mixed lymphocyte reactions in cultures of responding cells from a single subject and a pool of stimulating cells from two or more donors exhibited a synergistic response. Increased activity of the responding cells showed a positive correlation with the pool size. Treatment of the responding cells, stimulating cells or both with neuraminidase significantly increased the response.

Increased tolerance of leukemic mice to arabinosyl cytosine with schedule adjusted to circadian system.

Mice (BDF(1)) inoculated with L1210 leukemia survive for a statistically significantly longer span when four courses of arabinosyl cytosine are administered at 4-day intervals-not in courses consisting of eight equal doses at 3-hour intervals, but in sinusoidally increasing and decreasing 24-hour courses, the largest amount being given at previously mapped circadian and circannual times of peak host resistance to the drug. This finding relates to the many therapeutic situations involving rhythmic, and thus predictable, cycles in the host's tolerance of undesired effects from the agent used.

Simplified whole blood method for evaluating in vitro lymphocyte reactivity of laboratory animals.

A whole blood culture technique has been employed to quantitatively evaluate lymphocyte reactivity of small laboratory animals including mice, rats, guinea-pigs and rabbits. This simplified method has been used to study the blastogenic response to phytohaemagglutinin, concanavalin A, pokeweed mitogen and staphy-lococcal filtrate. Tuberculin-induced lymphocyte transformation responses have been studied in serial experiments using sensitized animals.