Reactivities of Reed-Sternberg (RS) cells for antibodies against T-lymphocytes and B-lymphocytes together with CD30 and CD15 were examined in the sequential biopsies of Hodgkin's disease (HD). For this purpose, six patients with lymphocyte predominant (LP) HD, each three of nodular and diffuse types, and three with mixed cellularity (MC) HD were examined. Numbers of times of biopsy in these cases were 25, the intervals between each biopsy ranged from 1 to 92 (median 12) mo. Positive reactivities of the RS cells for CD20, 45R, w75, w74, and/or MB1 were observed in all but one with nodular LPHD. Five of six cass with LPHD showed positive reaction for CD30 and/or CD15. RS cells in all of the present MCHD cases showed a positive reaction for CD30 with each one case showing positive reaction for CD15, CD20, and w75. RS cells in two of three cases with MCHD showed a positive reaction for CD20 or w75. RS cells did not show positive reaction for any antibodies against T-lymphocytes. Sequential biopsy revealed that two of three cases with nodular LPHD and one of three with diffuse LPHD changed to MCHD and two of three with MCHD changed to LDHD. Reactivity of RS cells for CD30 was consistent even when the histologic subtypes changed. Expression of CD15 by RS cells was labile; appearance of disappearance of this antigen during sequential biopsy was frequent. Positive reactivities of RS cells for anti-B-lymphocytes antibodies in LPHD cases disappeared in two cases when histology changed to MCHD. In one case with MCHD, the RS cells became reactive for anti-B-lymphocytes antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)