ABSTRACT
OBJECTIVE: To evaluate the application of fine needle aspiration cytology and fluorescence quantization-polymerase chain reaction (FQ-PCR) in the diagnosis of mycobacterial lymphadenitis. METHODS: Samples obtained by fine needle aspiration cytology (FNAC), which showed granulomatous lesions, from patients with lymph node tuberculosis also confirmed by response to antituberculosis therapy, was subjected to FQ-PCR to test M. tuberculosis DNA (TB-DNA), and the acid-fast bacillus stain. The positivity of TB-DNA and the acid-fast bacillus stain results were analyzed in different types of cases classified by cytology. Wilcoxon test was used to compare different cytology results, the positive rates of acid fast stain and the copy numbers of TB-DNA. RESULTS: Among the 72 cases, 46 were TB-DNA positive (46/72, 64%). By cytology examination, 7 cases were classified as type I, while 34 as type II and 31 as type III, in which the TB-DNA positive rates were 0% (0/7), 21/34 (61%) and 25/31 (81%) respectively. Sixty-four cases were subjected to the acid-fast bacillus stain and 14 were positive 14/ 64(22%). These 14 cases were all TB-DNA positive. The copy number of TB-DNA was significantly different between type II and type III cases (z = -2. 514,P < 0.05), and between acid fast stain positive and negative cases (z = -4.778, P < 0.05). CONCLUSIONS: FQ-PCR is a useful method for the diagnosis of mycobacterial lymphadenitis and could be used with FNAC, with a higher sensitivity than acid-fast bacillus stain.
Subject(s)
Biopsy, Fine-Needle , Polymerase Chain Reaction/methods , Tuberculosis, Lymph Node/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Tuberculosis, Lymph Node/pathology , Young AdultABSTRACT
A novel tuberculosis (TB) gene vaccine containing mouse granulocyte macrophage-colony stimulating factor (mGM-CSF) and a TB antigen (Ag85A) was developed in this study. The genes encoding Ag85A and mGM-CSF were amplified by PCR respectively from the Ag85A-containing pBSby5 and pC-mGM-CSF. The genes were then cloned into two different polylinker sites of plasmid pIRES, forming a novel TB gene vaccine construct pI85AGM. Following transfection of pI85AGM plasmid into 7721 cell line by Lipofectamine(TM), the expression of Ag85A and GM-CSF proteins was identified by Western blotting or RT-PCR. Then Balb/c mice were inoculated with the recombinant pI85AGM, pI85A, pIGM or plasmid alone, respectively. The activities of CTL, NK cells and the Ag85A-stimulated proliferation of spleen cells were measured by MTT method. The serum antibody against Ag85A was detected by ELISA. The results showed that the Ag85A and GM-CSF proteins could be expressed in 7721 cell line and the activity of CTLs and the proliferation of spleen cells were significantly increased in the pI85AGM-immunized mice, indicating that the pI85AGM-immunized mice could generate specific immune responses to Ag85A. This study might provide possibility for developing novel anti-TB gene vaccine.
