1) Induction of humoral antibody formation involves the obligatory recognition two determinants on an antigen, one by receptor antigen-sensitive cell and other carrier (associative interaction). 2) Paralysis only determinant cell; that is, a nonimmunogenic molecule (a hapten) can paralyze cells. 3) There is competition between paralysis induction at level cell. 4) The mechanisms low- high-zone paralysis, maintenance unresponsive state, are identical. 5) High-zone occurs when both saturated,...

A transplantable, murine reticulum cell sarcoma is described which exhibits the cytologic, adherence, and phagocytic properties of macrophages. It forms specific rosettes with erythrocytes in presence corresponding anti-serum. The ascites cells mediate antibody-dependent cellular immunity as assayed by release radioactivity from 51Cr-labeled erythrocytes. contribution contaminating host cytotoxic reaction was ruled out growing tumor F1 mice removing anti-H2 serum complement. have receptors...

Mouse tumor C1300 has been established in tissue culture. The cells have a round cell morphology both the subcutaneous and suspension However, when given surface on which to attach, they send out processes up 3 mm length assume of mature neurons. attached are stained by Bodian silver procedure for neurons, whereas grown not. Electron microscopy reveals that contain neurofilaments, neurotubules, densecore vesicles indicative nerve fibers. Both free-floating tyrosine hydroxylase activity...

Mouse lymphoma cells in culture which are killed by adrenal steroids contain specific cortisol receptors that may be involved the initial events of hormone action. The similarity these to those hepatoma tissue cells, where induce tyrosine aminotransferase, suggests certain aspects steroid action similar two systems. In three steroid-resistant cell populations binding was less than parent lines, suggesting conversion resistance associated with changes binding.

Mitogen-induced cytotoxicity was studied by culturing mouse spleen cells with an optimum mitogenic dose of concanavalin A (Con A) for 2 days and, after washing, assessing their ability to lyse tumor targets. We show that rapid lysis occurs only when the correct concentration agglutinating mitogen (phytohemagglutinin P (PHA) or Con is present in assay. PHA more efficient than revealing cytotoxic effect. The A-induced effector cell shown be sensitive anti-theta serum and complement. Cytotoxic...

A new subclass of mouse IgG for which we propose the name IgG3 has been shown to have a mol wt 150,000 consistent with an L(2)H(2) structure, and is present in normal serum at concentration 0.1-0.2 mg/ml. Its molecular weight, low carbohydrate content, glycopeptide analysis, C-terminal analysis are all typical class. The intact protein had strong tendency form noncovalent aggregates itself were dissociable acid. Upon papain digestion Fab fragment 47,000 mole was generated along Fc insoluble...

Abstract Inbred mice immunized with the pneumococcal C carbohydrate produce plaque‐forming cells directed exclusively against phosphorylcholine determinants of this antigen. The antibody responsible for plaque formation is restricted heterogeneity respect to its affinity phosphorylcholine. Mouse anti‐serum an idiotype shared by certain BALB/c anti‐phosphorylcholine plasmacytoma proteins specifically inhibits approximately 70% plaques induced C‐carbohydrate in mice. expression idiotype, as...

The observation has been made repeatedly that the induced synthesis of many different enzymes can be inhibited by a wide variety carbohydrates (Benzer, 1953; Cohn, 1957, 1958; Epps and Gale, 1942; 1943; Happold Hoyle, 1936; Herzenberg, Monod, 1941, 1947, 1956; Monod 1952; Neidhardt Magasanik, 1956). One most characteristic potent these carbohydrate inhibitors is glucose. As result general phenomenon called glucose effect (Cohn, Cohn 1953). During an investigation effect, it was observed...

Evidence is presented that antigen-sensitive cells require two signals for induction. Normally these are delivered to the cell via recognition of determinants on immunogen: first receptor cell, and second by cooperating system. The special experimental situation described here depends upon observation bacterial lipopolysaccharides (LPS) render immunogenic a variety haptens. When monovalent haptens (TNP-amino acids) added spleen cultures, specific antihapten responses induced in presence LPS....