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CrossRef Open Access 1982
Description of a Qa‐2 like alloantigen (Qa‐m2)

P. Mark Hogarth, Pauline E. Crewther, Ian F. C. McKenzie

AbstractSeveral new aspects of the chemistry, genetics and cellular distribution of the murine Qa‐2 alloantigen were apparent in an analysis of this antigen using monoclonal antibodies recognizing a Qa‐2‐like antigen called Qa‐m2. Immunoprecipitation and sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis identified the Qa‐m2 alloantigen as a two‐chain structure composed of a 39 000 dalton heavy chain and a 12000 light chain which is probably β2‐microglobulin; the heavy chain was readily distinguished from that of H‐2. In addition, the expression of Qa‐m2 alloantigens on the cell surface was found to be controlled by the H‐2D gene with H‐2Db strains carrying approximately 8‐10 times greater amounts of Qa‐m2 than strains carrying the H‐2Dd or H‐2Dq alleles. Finally, the Qa‐m2 antigen, found predominantly on peripheral T cells, was present on only 10% of thymus cells. However, subpopulations of B cells (approximately 25% of all B cells) and bone marrow cells (15‐20%) were also reactive. The monoclonal anti‐Qa‐m2 antibodies differed in their reactions from that reported for the conventional anti‐Qa‐2 sera, which must, therefore, be complex. The monoclonal antibodies may be useful reagents for functional analysis of T and B cell subpopulations.

CrossRef 2023
Guide to QA of ODFL Provision in the Pacific

Commonwealth of Learning (COL)

This guide to quality assurance of Open, Distance and Flexible Learning (ODFL) provision is intended to support Ministry of Education officials and teachers in the Pacific to roll out high quality distance education in their own contexts. Whilst expansion of ODFL has significantly increased participation in education, upholding the quality of provision cannot be overemphasised. The guide contains six units: (1) Understanding quality and quality assurance in ODFL; (2) Key components of quality in ODFL; (3) Implementing quality in ODFL; (4) Enhancing quality through policy; (5) ICT infrastructure and quality; and (6) optional readings. This guide was developed as part of the Partnership for Open, Distance and Flexible Learning in the Pacific Project, supported by Ministry of Foreign Affairs and Trade, New Zealand.

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