{'fraction_non_alphanumeric': 0.025961538461538463, 'fraction_numerical': 0.0057692307692307696, 'mean_word_length': 5.894039735099338, '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}}
Surface Antigen Changes Accompanying Lymphocyte Activation

It is here shown that some noncongenic anti‐H‐2 antisera produced by using normal spleen cells as the immunogen can contain cytotoxic antibody activity against activated, but not resting, lymphocytes of unrelated H‐2 haplotype strains. Reactivity was noted against lymphocytes activated in vitro with T‐ or B‐cell mitogens, or in vivo by antigenic stimulation. Analysis of the results indicated that the anti‐activated lymphocyte activity was most likely related to production of anti‐Ala‐1 (‘activated lymphocyte antigen’) alloantibodies. This appears to occur as a result of donor lymphocyte activation during production of the anti‐H‐2 antisera, using Ala‐1‐incompatible donor and recipient combinations, where the donor cells are competent to recognize and react against host H‐2 incompatibilities. These results confirm the finding that lymphocyte activation can be accompanied by the expression of an antigen that is either absent or weakly expressed on resting lymphocytes.