Comparison of three culture media for isolation of Mycobacterium tuberculosis: a 6-year study.

Among 2,648 specimens positive on culture for Mycobacterium tuberculosis over a 6-year period, 82% grew on Lowenstein-Jensen medium (LJ), 79% on American Trudeau Society (ATS), and 56% on Middlebrook 7H10 (7H10). When these commercial culture media were compared in regard to the number of acid-fast bacilli seen on the original smears, LJ cultures were found to have the highest isolation rates for each smear category, and 7H10 had the lowest rates. Comparing the media from the aspect of number of mycobacterial colonies produced, LJ and ATS had the highest average colony counts, followed by 7H10.

Properties of lymphocytes which confer adoptive immunity to tuberculosis in rats.

Following immunization of rats with BCG there was added to thoracic duct lymph a population of sensitized lymphocytes which conferred adoptive immunity to tuberculosis upon syngeneic recipients. At an early stage of immunization, 5 days after BCG inoculation, the sensitized cells were large and medium lymphocytes as evidenced by their sensitivity to vinblastine. On day 8, the sensitized cell population was partially resistant to vinblastine and by day 28 it was totally resistant.

Immune response to Mycobacterium tuberculosis in rats.

After intravenous injection into rats, both the attenuated strain R1Rv and the virulent strain H37Rv of Mycobacterium tuberculosis grow in the liver and spleen. However, the infected rats mount a specific immune response with great rapidity, giving a false impression of natural resistance to the tubercle bacillus. Adoptive immunity to tuberculosis was achieved by transferring thoracic duct cells from immunized donors to normal syngeneic recipients.

The mediator of cellular immunity. VI. Effect of the antimitotic drug vinblastine on the mediator of cellular resistance to infection.

The antimitotic drug vinblastine (Vbl) has a profound impact upon the specifically sensitized lymphocytes that transfer cellular resistance to Listeria monocytogenes. A 12-h pulse of the drug given to prospective donors during the first week of an immunizing Listeria infection inhibits the delivery of protective lymphocytes to the thoracic duct and their subsequent movement into an inflammatory exudate induced in the peritoneal cavity. The effect of Vbl is clearly related to its antimitotic activity, not to an effect on lymphocytes regardless of their position in the division cycle.

Development of enzymes in the cotyledons of watermelon seedlings.

Changes in hypocotyl length, cotyledon weight, lipid content, chlorophyll content, and capacity for photosynthesis have been described in seedlings of Citrullus vulgaris, Schrad. (watermelon) growing at 30 C under various light treatments. Corresponding changes in the levels of 19 enzymes in the cotyledons are described, with particular emphasis on enzymes of microbodies, since during normal greening, enzymes of the glyoxysomes are lost and those of leaf peroxisomes appear.

The mediator of cellular immunity. 3. Lymphocyte traffic from the blood into the inflamed peritoneal cavity.

A substantial portion of the lymphocyte-like cells in induced peritoneal exudates derive from cells which enter the blood by way of the thoracic duct. The migrant cells have been identified as large and medium lymphocytes, but they may also include short-lived small lymphocytes derived from them. Small lymphocytes which have a potentially long circulating life-span are excluded from exudates, although cells of this type predominate in thoracic duct lymph.

The mediator of cellular immunity. II. Migration of immunologically committed lymphocytes into inflammatory exudates.

Peritoneal exudates from rats which have survived an infection with L. monocytogenes can protect cyclophosphamide-treated recipients against a Listeria challenge. They are more effective in this respect than cells obtained from the spleen or thoracic duct lymph.

The mediator of cellular immunity. I. The life-span and circulation dynamics of the immunologically committed lymphocyte.

Thoracic duct cells from rats which have survived an infection with Listeria monocytogenes can confer a high level of antimicrobial resistance upon normal recipients. The cells which confer protection appear in the thoracic duct during the 1st wk of the immunizing infection, at a time when newly formed lymphocytes are being added to the lymph in substantially increased numbers. The protective cells differ in at least two respects from the majority of small lymphocytes in central lymph: they have a rapid turnover rate and a short life-span in the circulation.