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U Botzenhardt

Publications and source records attributed to U Botzenhardt.

28 records · Page 2Linked to original sources
PubMed1976

[Immunopathological genesis of pancreatitides].

Antinuclear factors in serum were determined in 37 patients with acute and 50 with chronic pancreatitis. Of the 5 with acute pancreatitis of unknown etiology, 4 had serum antinuclear factors in high titers; of the 16 with chronic pancreatitis of unknown etiology, 10 had serum antinuclear factors in high titers and 4 in low titers.

Acute Disease↗
PubMed1975

Kinetics of the reactive cell clones after immunosuppression and induction of tolerance. II. Different recovery of 19 S and 7 S plaque-forming cells after induction of tolerance.

By the aid of two alkylating agents (cyclophosphamide (CP) and 036.5122, (Asta), applied after a single dose of antigen, tolerance to sheep red blood cells (SRBC), has been induced in NMRI mice. Duration and characteristics of recovery were followed by a second antigenic challenge at various time intervals and by determination of 19 S and 7 S plaque-forming cells (PFC) 4 days later. During recovery from the tolerant state two phases of responsiveness could be differentiated: an early phase with no or markedly reduced numbers of total PFC, all of them being of the IgM type; a later phase with a steady increase in total PFC up to normal values, paralleled by an increase in the proportion of 7 S PFC finally reaching 90% of total PFC. In comparison with CP, recovery from tolerance induced by equitoxic doses of 5122 were delayed and modified. Even after 8 weeks, total PFC to SRBC were still depressed, and the ratio 19 S/7 S PFC resembled neither a typical primary nor secondary pattern. It is concluded that CP-mediated immunological tolerance is followed spontaneously by the establishment of a memory state. This observation, in agreement with findings of other authors, is interpreted as the expression of an established B cell memory compartment during the period of deficient T cell activity. The long-lasting modification of specific responsiveness after 5122 indicates a profound disturbance of the potency to recover from the impact of this alkylating agent, the biological base of which is as yet unidentified. It is suggested that observation of the characteristic features during the recovery phase from tolerance may help to clarify the nature of the defect in specific responsiveness.

Animals↗
PubMed1975

Kinetics of the reactive cell clones after immunosuppression and induction of tolerance: (1) inhibition of 19 S and 7 S plaque-forming cells in the primary and secondary immune response to sheep red blood cells by cyclophosphamide and 036.5122 (Asta).

The kinetics of the reactive cell clones after primary and secondary immunization with SRBC1) modified by cyclophosphamide and a newly synthesized cyclophosphamide analogue 036.5122 (Asta), have been studied. After primary immunization, both substances caused a severe and dose dependent depletion of 19 S PFC2). The 7 S PFC in the late primary response were only slightly inhibited by cyclophosphamide in low dose ranges, indicating, that sensitization could not be prevented by this substance. In contrast, 0.36.5122 was fully able to suppress 7 S PFC. Thus, treatment with 0.36.5122 after primary immunization can fully prevent the expression of the specific response. Experiments dealing with inhibition of a secondary immune response revealed that both test substances were able to strongly suppress the 19 S as well as the 7 S PFC. In general, 036.5122 demonstrates a higher suppressive potency, and the timing of its application for optimal suppression is less delicate than that of cyclophosphamide. 036.5122 was equally well inhibitory, whether given directly before or after antigenic challenge. The hypothesis is discussed, whether the immunosuppressive effect of 036.5122 given before antigenic challenge in the secondary immune response is due to cytotoxic damage of antigen reactive clones stimulated by persisting antigen.

Animals↗
PubMed1975

Cyclophosphamide-induced immunological tolerance: recovery leads to a memory state.

Tolerance to SRBC has been induced in adult mice by the aid of cyclophosphamide, and the duration of the tolerant state has been tested by a second injection of antigen at different times thereafter. As evidenced by 19S and 7S PFC 4 days after challenge, tolerance in this model is of relatively short duration and leads spontaneously to a memory state.

Animals↗