Continued growth of functional human T lymphocytes: Production of human T-cell growth factor

Monkey Interleukin 2: Optimal Conditions for Production and Partial Characterization

“…The decline in IL 2 activity with culture time may be attributed to the adsorption of IL 2 by culture-generated lymphoblast oid cells possessing IL 2 receptors, as has been shown in other species [16,22], It was also shown in the cynomolgus monkey sys tem like in the murine system that Con A induced higher IL2 activity than PH A, while it was reported in human [ I ] and canine [5] systems that PHA induced higher 1L2 activity than Con A. These findings agreed with the previous observation that cynomol gus monkey lymphocytes showed higher blastogénie response to Con A than to PHA [28], Addition of PMA, known as a tumor promoter, re sulted in enhancement of IL2 production in lympho cyte cultures of cynomolgus monkeys, in agreement with the results obtained with murine cells [7], In con trast, the presence of xenogenic lymphoblastoid cell lines did not augment the 1L2 production whether they were of T or B cell origin; this is in contrast to the results obtained with human systems [3,14], The rea son for this discrepancy cannot be readily obtained. One possible explanation is that as promotion of IL 2 production by lymphoblastoid cell lines may be mod ulated by the presence of la antigens on the surface of cell lines [12,17], not enough cellular interaction to augment IL2 production through la antigens was conducted due to species difference between cyno molgus monkey lymphocytes and human cell lines.…”

T Cell Growth Factor from Human Splenic Cell Cultures: Conditions for Its Production, and Its Utilization for Maintenance of Cytotoxic T Cell Lines

“…As in the human PBL system (4,8), the yield of TCGF from PHA-stimulated human spleen cell cultures was augmented by the addition of 1.0 {tM indomethacin, an inhibitor of prostaglandin synthetase, or of LCL cells to the cultures, or by irradiation of the spleen cells to be cultured. The irradiation of the spleen cells to be stimulated with PHA might suppress generation of PHA-lymphoblasts capable of absorbing TCGF produced in the culture.…”

In vitro Proliferation of Murine Spleen Cells: Inhibition by Monoclonal Antibodies to L3T4 and Lyt-2 T Cell Markers or Intracellular Cyclic Adenosine Monophosphate

“…It seems that, in all in stances, proliferation involves IL-2, since it was documented that stimulation with both ConA [18] and phorbol ester and calcium ionophore [30,31] results in endogenous production of IL-2 by stimulated cells. In complete inhibition by the two antibodies added together may reflect the fact that some proliferating cells probably belong to an NKlike subset that responds to IL-2, but does not express the L3T4 and Lyt-2 markers.…”

“…Previous results suggested that the anti bodies actually interfere with the effect of IL-2 that is generated during stimulation with ConA [18].…”