{'fraction_non_alphanumeric': 0.04296455424274973, 'fraction_numerical': 0.04779806659505908, 'mean_word_length': 4.6626139817629175, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Receptors for Immunoglobulins on Resting and Activated Human T Cells

Studies of cell surface markers expressed by sets of human lymphocytes with various functions has been an area of most intensive investigation in the last few years. This line of research has been stimulated by the concept that lymphocyte surface markers may be involved in functional activities and/or cellular interactions. Thus it has been well documented that surface immunoglobulin (Ig), the main marker of mature B cells (Pernis et al. 1970, Raff et al. 1970) is directly involved in antigen-induced B cell activation. On the other hand, the prototype of human T cell surface markers, the receptor for sheep erythrocytes (E) (Jondal et al. 1972), does not seem to be involved in any T cell activity. Recently, subsets of human T cells were defined by different markers such as receptors for various lectins (Hammarstrom et al. 1973), histamine receptors (Saxon et al. 1977) and expression of la (Evans et al. 1978a Greaves et al. 1979, Yu et al. 1980, Reinhertz et al. 1979a, Winchester & Kunkel 1980). Some of these markers have been reported as defining "functional" subsets of cells (Evans et al. 1977, 1978b Reinhertz et al. 1979b,c), whereas others, such as la antigens and a group of four distinct mononuclonal antibodies (Corteetal. 1981), appear to be expressed only on activated T cells. Most of the presently familiar surface markers do not appear to be directly involved in T cell functions. An important exception is the surface receptor for the Ec portion of Ig (FcR) which are known to be involved in effector functions, such as antibody dependent cellular cytotoxicity (ADCC) (Perlmann etal. 1976, Perlmann& Cerottini 1979, Lamon etal. 1975, 1976, 1977) or inhibition of TorBcell proliferation in certain/nv/7ro systems (Moretta et al. 1977a, 1979, Canonica et al. 1981).