Optimization and Validation of a Harmonized Protocol for Generating Therapeutic-Grade Dendritic Cells in a Randomized Phase II Clinical Trial, Using Two Varied Antigenic Sources.

Autologous dendritic cell (DC)-based immunotherapy is a cell-based advanced therapy medicinal product (ATMP) that was first introduced more than three decades ago. In the current study, our objective was to establish a harmonized protocol using two varied antigenic sources and a good manufacturing practice (GMP)-compliant, manual method for generating clinical-grade DCs at a limited-resource academic setting. After obtaining ethical committee-approved informed consent, the recruited patients underwent leukapheresis, and single-batch DC production was carried out. Using responder-independent flow cytometric assays as quality control (QC) criteria, we propose a differentiation and maturation index (DI and MI, respectively), calculated with the QC cut-off and actual scores of each batch for comparison. Changes during cryopreservation and personnel variation were assessed periodically for up to two to three years. Using our harmonized batch production protocol, the average DI was 1.39 and MI was 1.25. Allogenic responder proliferation was observed in all patients, while IFN-gamma secretion, evaluated using flow cytometry, was detected in 10/36 patients and significantly correlated with CD8+ T cell proliferation (p value-0.0002). Tracking the viability and phenotype of cryopreserved MDCs showed a >90% viability for up to three years, while a mature DC phenotype was retained for up to one year. Our results confirm that the manual/semi-automated protocol was simple, consistent, and cost-effective, without the requirement for expensive equipment and without compromising on the quality of the final product.

Development and Evaluation of p16 based Double Antibody Sandwich ELISA for Detection of Cervical Precancer and Cancer.

OBJECTIVE: Cervical cancer is the third most common cancer in women, worldwide. This study was designed to develop an affordable, accurate and simpler screening test like Enzyme-linked immunosorbent assay (ELISA) which is low cost and will help in bringing down the disease burden in resource poor countries. METHODS: In this study, we have raised and evaluated monoclonal antibodies against recombinant p16 using immunohistochemistry (IHC), western blot, immunoprecipitation and ELISA. Double antibody sandwich ELISA (DAS-ELISA) and cytokeratin ELISA was designed for screening women with cervical dysplasia and cancer. RESULTS: Cloned, expressed and purified recombinant p16 were used for generation of monoclonal antibodies. After initial screening, six clones were selected, and affinity purified. Except 155D11G10, which was isotype Immunoglobulin (Ig) G1 all the others were found to be IgG2b. 133A6G5 and 151A7B9 were found to be best for p16 IHC, both showed 70 - 80% and 80 - 90% of nuclear staining respectively. All the antibodies positively detected p16 from the HeLa lysates in western blot except 133A6G5. Studies using immunoprecipitation showed 133A6G5, specifically detected p16. DAS-ELISA developed using a combination of our p16 monoclonal antibodies showed sensitivity of up to 2pg. A pilot study using DAS-ELISA and cytokeratin ELISA in cervical samples revealed the assay sensitivity and specificity as 100% and 80%, respectively. CONCLUSION: Using combination of DAS-ELISA and cytokeratin ELISA we have developed an accurate and reliable method for the early detection of cervical cancer in a subject, with minimal false results. In the future after large scale validation, p16 ELISA could be used as a reliable tool for diagnostic purposes.

Combination of IDO1high and CCL19low expression in the tumor tissue reduces survival in HPV positive cervical cancer.

The over expression of Indoleamine 2, 3-Dioxygenase (IDO1), an immune checkpoint inhibitor, is well known in cervical cancer. However, its association with chemokine signals promoting cellular infiltration in the cervical tumor microenvironment, is unknown. In the current study, we evaluated the expression and enzymatic activity of IDO1. We also profiled the expression of chemokine ligand-receptors- CCR4-CCL22, CXCR3-CXCL10, CXCR4-CXCL12, and CCR7-CCL19 using immunohistochemistry (IHC), and studied their association with IDO1, statistically. After getting an informed consent, punch biopsy samples were obtained from 105 patients diagnosed with cervical cancer. HPV typing by Sanger sequencing, realtime PCR for quantifying IDO1 mRNA expression, HPLC for determining the K/T ratio and IHC for all the above chemokine receptor-ligand pairs along with IDO1 were performed. We found a significant increase in the expression of IDO1 and K/T levels in early and locally advanced stages when compared to Stage IV disease. Among the chemokine ligand -receptor pairs profiled, we found that high CCL19 marker expression was a good prognostic indicator of patients' disease-free (p = 0.013) and overall survival (p = 0.043). Although we could not identify IDO1 as an independent prognostic factor, we found that high levels of IDO1 expression may further reduce survival outcomes in patients with low CCL19 expression. This could be vital for designing immuno therapeutic interventions targeting IDO1.

Analysis of Kynurenine/Tryptophan ratio and expression of IDO1 and 2 mRNA in tumour tissue of cervical cancer patients.

OBJECTIVES: Indoleamine 2,3-Dioxygenase (IDO) catalyses the degradation of the essential amino acid tryptophan leading to the production of immunosuppressive Kynurenine. In the present study, we developed a modified method for measurement of Kynurenine/tryptophan (K/T) ratio in the cervical tissue using HPLC and investigated its relationship with the expression of IDO1 and 2 genes in the cervical tumour milieu. DESIGN AND METHODS: Cervical cancer punch biopsy samples of 27 women who presented at the Cancer Institute (WIA) were used for detection of K/T ratio by HPLC as well as expression of IDO1 and 2 at the mRNA level by Realtime PCR after obtaining Institutional ethical committee approval. RESULTS: The K/T ratio was elevated significantly in cancer cervix samples compared to normal cervix (p<0.05). IDO1 mRNA levels were up-regulated whereas IDO2 mRNA levels were down-regulated in cancer cervix compared to the normal cervix. A positive correlation was observed between IDO1 and K/T (p<0.05) indicating that IDO1 was responsible for the increase in K/T ratio. CONCLUSION: Our preliminary data indicates that the K/T ratio at the tissue level may be investigated reliably using HPLC, as an indirect measure of IDO1 gene expression and activity.