Ankita Thakur is pursuing her Ph.D. degree. She is working as Senior Research Fellow (fellowship granted by DST INSPIRE, India) in Department of Zoology, Panjab University, Chandigarh, India. Presently, she has published four papers in reputed journals. Major part of her research is focussed on designing of anti-leishmanial vaccines. As a part of her research she is testing the immunoprophylactic potential of killed parasite antigens as vaccine candidates against murine visceral leishmaniasis.
Visceral leishmaniasis (VL) is a neglected tropical disease caused by protozoan parasites of the Leishmania donovani complex. An estimated 200 000 to 400 000 new cases are reported annually. Control of VL infection till date relies on chemotherapy. The therapeutic armamentarium for VL is currently plagued with several limitations as the available drugs are toxic, expensive and need to be administered for extended periods. So there is an urgent need to find another alternative in the form of a vaccine. Killed vaccines composed of parasite fractions or whole killed parasites reached phase 3 clinical trials, but showed a limited prophylactic efficacy. It seems that major limiting factor for the development of killed vaccines is lack of a suitable adjuvant. Therefore, the aim of the present study was to enhance the protective efficacy of Killed Leishmania donovani (KLD) antigen by using different adjuvants. Inbred BALB/c mice were immunized with KLD antigen alone and in combination with four different adjuvants i.e. alum, saponin, MPL-A and cationic liposomes. Three immunizations were carried out at an interval of two weeks. Two weeks after last booster challenge infection was given and mice were sacrificed on different post challenge days. Protective efficacy of vaccines was analyzed by assessment of parasite burden and generation of cellular and humoral immune responses. All the formulations were found to be immunogenic and imparted significant protection. However, level of protection varied with the type of adjuvant used. Our findings suggest promising antileishmanial potential of KLD as an antigen candidate in combination with cationic liposomes and MPL-A as adjuvants against murine visceral leishmaniasis.
Kgomotso P Sibeko-Matjila has completed her PhD in 2009 from University of Pretoria, South Africa. Subsequently, she was appointed as a Senior Lecturer in the Department of Veterinary Tropical Diseases, University of Pretoria. She has authored and co-authored nine papers in reputed journals and is currently a Primary Supervisor to three PhD and four MSc students.
Theileria parva, an apicomplexan intracellular protozoan parasite, infects and transforms bovine and buffalo lymphocytes causing 2 recognized disease syndromes in cattle, East Coast Fever (ECF) and Corridor Disease (CD). It is still not clear as to why T. parva infections cause different disease syndromes in cattle. In order to study strain-specific changes in gene expression in ECF and CD isolates, Next Generation Sequencing was used to analyze transcriptome of T. parva Muguga and T. parva 7014, respectively. RNA sequence analysis revealed differential expression of 1048 genes between the two isolates. The majority of DEGs were genes encoding sub-telomeric fragment-related protein family (SVSP) (n=85) followed by ribosomal proteins (n=33), membrane/inter-membrane proteins (n=32), signal peptide containing proteins (n=24), transcription/translation/elongation factors (n=23), transporters (n=15) and antigens (n=13). Forty pathways were affected by products of DEGs. The findings of this study provide evidence of variations in gene expression between ECF and CD strains investigated, with most DEGs down-regulated in T. parva 7014 (n=742, 70.8%). Furthermore, genes involved in the ability of the parasite to transform host cells, including members of CD8+ T-cell target antigens, TA9/TP9, SVSP and TashAT gene families, may be the objects of further investigations into understanding the molecular dynamics of ECF and Corridor disease. Many of the DE genes were hypothetical proteins (340), emphasising the need to identify their biological function in order to elucidate their molecular importance in the genetic diversity of T. parva parasites.