We have devised a procedure for the identification of individual molecules which are associated with the mitotic spindle apparatus and cytoskeleton in mammalian cells. We prepared monoclonal antibody-producing hybridomas by immunizing mice with mitotic spindles isolated from cultured HeLa cells. Among several antibody-producing clones obtained, one hybridoma (22MA2) produced an antibody that recognizes a putative microtubule-associated protein which exhibits unusual distribution characteristics in cultured cells. Immunofluorescence studies showed that during mitosis the 22MA2 antigen is distributed in parallel with the spindle fibers of the mitotic apparatus, and that during interphase the antigen is always associated to a limited extent with cytoplasmic microtubules. Also, the co-distribution of the antigen with microtubules was found to be Colcemid sensitive. However, the 22MA2 antibody immunofluorescently stained the nuclei of cells in the exponential growth phase, but did not stain the nuclei of cells that had grown to confluence. This nuclear fluorescence appears to be directly related to cell density rather than nutritional (serum) factors in the growth medium. The results suggest that the antigen undergoes some change in structure or distribution in response to changes in the proliferative capacity of the cell. Biochemical analyses of cytoplasmic, nuclear, and mitotic spindle subcellular fractions show that the antigen exhibits a polypeptide molecular weight of 240,000 is found in various mammalian cells ranging from marsupial to human, and is particularly susceptible to proteolysis.

BACKGROUND: Optimal drug dosing is important to ensure adequate response to treatment, prevent development of drug resistance and reduce drug toxicity. The aim of these clinical standards is to provide guidance on 'best practice´ for dosing and management of TB drugs.METHODS: A panel of 57 global experts in the fields of microbiology, pharmacology and TB care were identified; 51 participated in a Delphi process. A 5-point Likert scale was used to score draft standards. The final document represents the broad consensus and was approved by all participants.RESULTS: Six clinical standards were defined: Standard 1, defining the most appropriate initial dose for TB treatment; Standard 2, identifying patients who may be at risk of sub-optimal drug exposure; Standard 3, identifying patients at risk of developing drug-related toxicity and how best to manage this risk; Standard 4, identifying patients who can benefit from therapeutic drug monitoring (TDM); Standard 5, highlighting education and counselling that should be provided to people initiating TB treatment; and Standard 6, providing essential education for healthcare professionals. In addition, consensus research priorities were identified.CONCLUSION: This is the first consensus-based Clinical Standards for the dosing and management of TB drugs to guide clinicians and programme managers in planning and implementation of locally appropriate measures for optimal person-centred treatment to improve patient care.