title: Time-course study of the immunotoxic effects of the anticancer drug chlorambucil in the rat.
abstract: In 2005, the International conference on harmonization (ICH) recommended that all new human pharmaceuticals be tested for unintended immunomodulatory potential via a tiered approach. Included in this approach is a semiquantitative description of changes in the separate compartments of lymphoid tissue (also called enhanced histopathology). Chlorambucil was administered to Hanover Wistar rats at regular time points, followed by a treatment-free (recovery) period. Groups of treated and control animals were sacrificed regularly during both the treatment and recovery periods. Selected tissues were removed, weighed fresh and fixed in formalin, processed, and stained with hematoxylin and eosin. Blood samples and bone marrow smears were also obtained. With the use of enhanced histopathology, a description of the changes in lymphoid tissues and bone marrow was used as a means of assessing the susceptibility, and recovery, of the different lymphoid cell populations over time. A correlation with organ weights, flow cytometry data, and bone marrow cytology was achieved. The administration of chlorambucil in the Hanover Wistar rat provided a useful tool to examine the rate and sequence of changes in the lymphoid organs and bone marrow during treatment with, and the recovery from the effects of, a potent immunosuppressive agent.
authors.affiliation: AstraZeneca, Safety Assessment UK, Mereside, Alderley Park, Macclesfield, Cheshire, UK.
authors.forename: Gail
authors.initials: G
authors.lastname: Pearse
authors.forename: Anne
authors.initials: A
authors.lastname: Pietersma
authors.forename: Jo
authors.initials: J
authors.lastname: Cunliffe
authors.forename: John R
authors.initials: JR
authors.lastname: Foster
authors.forename: John
authors.initials: J
authors.lastname: Turton
authors.forename: Nicola
authors.initials: N
authors.lastname: Derbyshire
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Randall
mesh_terms: D000818:Animals; D018906:Antineoplastic Agents, Alkylating / Q000633:toxicity*; D001835:Body Weight / Q000187:drug effects; D001853:Bone Marrow / Q000187:drug effects* / Q000276:immunology / Q000473:pathology; D002699:Chlorambucil / Q000633:toxicity*; D005260:Female; D000922:Immunotoxins / Q000633:toxicity*; D007700:Kinetics; D008198:Lymph Nodes / Q000187:drug effects / Q000276:immunology; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D023421:Models, Animal; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013154:Spleen / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D013950:Thymus Gland / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D013995:Time
chemical_list: D018906:Antineoplastic Agents, Alkylating; D000922:Immunotoxins; D002699:Chlorambucil