PMC9239536_01
Right knee images before surgery. (A) X-ray with no sign of osteoarthritis; (B) Computed tomography scan with normal TT-TG index (14mm) and C) patellar tilt (7 degrees); (D) T2-weighted magnetic resonance image in the axial plane with focal chondral lesion in the trochlear region (arrow); (E) T2-weighted magnetic resonance image in the sagittal plane view showing the same lesion (arrow)
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Real-time polymerase chain reaction for Mycoplasma pneumoniae from the first culture of chondrocytes derived from patient's cartilage. (A) Positive control; (B) No template control; (C) Media obtained from chondrocytes culture; (D) Plasma; (E) Cycle threshold values. Purple curve: internal control and green curve: mycoplasma
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A week later, the patient was subjected to another knee biopsy and the ensuing chondrocyte culture showed an accelerated cell growth, compared with the growth rate of the previous contaminated cell culture (Figure 2).
Real-time polymerase chain reaction for Mycoplasma pneumoniae from the second culture of chondrocytes derived from patient's cartilage. (A) Positive control; (B) No template control; (C) Media obtained from chondrocytes culture; (D) Cycle threshold values. Purple curve: internal control, green curve: mycoplasma
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However, reverse-transcriptase polymerase chain reaction (RT-PCR) was positive for Mycoplasma pneumoniae (Figure 3). Polymerase chain reaction analysis of the cell culture medium and plasma showed that the source of cell contamination was autologous serum (Figure 3).
Cumulative population doubling level of patient-derived chondrocyte cultures. Population doubling level was calculated using the following formula: PDL (Population doubling level) = log10 (N/N0) x 3.33. Culture 1: first culture of chondrocytes derived from patient's cartilage; Culture 2: second culture of chondrocytes derived from cartilage of the same patient. Culture 1 was found contaminated with mycoplasma and culture 2 was mycoplasma-free
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And it was neither detected in cell culture media (Figure 4).