Given the task definition and input, reply with output. Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

To analyze cell viability and morphology of primary cell cultures from CD133 immunolabeled and sorted cells from epithelium of patients suffering from benign prostate hyperplasia (BPH).', 'Cells obtained from 5 patients were divided in two fractions. First fraction (CD133+/CD133-) was cultivated in DMEM with 10% FBS. Second fraction was mixed with CD133 microbeads and immunomagnetically divided into CD133+ and CD133- fractions. These cells were cultivated and followed-up for 2 weeks. Cells were stained for Annexin V FITC/propidium iodide.', 'Seventy CD133+/CD133- cultures, thirty-one of CD133+ and thirty-one of CD133- cells were established. There were 5-fold and 3-fold increase of CD133+/CD133- and CD133+ cell number after 2 weeks, respectively. CD133+/CD133- and CD133+ monolayers displayed epithelial-like morphology and cytokeratine expression. CD133- cultures collapsed. Cell viability within CD133+ and CD133- populations was 90.1-/+6.3% and 24.3-/+6.2%, respectively. Apoptotic index was 9.0-/+6.1% and 28.5-/+23.8% within CD133+ and CD133- cultures, respectively.
Are progenitor cells responsible for formation of human prostate epithelium primary cultures?