Neetu Singh

CD8 T Cell Exhaustion in Human Visceral Leishmaniasis

Little is known about CD8 T cells in human visceral leishmaniasis (VL) and it is unclear if these cells have a protective, pathological and/or suppressive function. In experimental VL CD8 T cells have been shown to contribute to parasite control and play an important role in vaccine-generated immunity. To better understand the role of CD8 T cells in human VL, we examined molecules associated with anergy and cytotoxic T lymphocytes (CTL) in peripheral blood mononuclear cells (PBMC) and splenic aspirates (SA), and in CD8 cells derived from these tissues. Gene and surface marker expression suggest that splenic CD8 cell predominantly display an anergic phenotype, whereas CD8-PBMC have features of both anergic cells and CTLs. CD8 cells contribute to the baseline IFNγ levels in whole blood (WB) and SA cultures, but not to the Leishmania induced IFNγ release that is revealed using WB cultures. Blockade of CTLA-4 or PD1 had no effect on IFNγ production or parasite survival in SA cultures. Following cure, CD8 T cells contribute to the Leishmania induced IFNγ production observed in Leishmania stimulated cell cultures. We suggest CD8 T cells are driven to anergy/exhaustion in human VL, which affect their ability to contribute to protective immune responses.

Leishmania specific CD4 T cells release IFNγ that limits parasite replication in patients with visceral leishmaniasis.

Visceral leishmaniasis (VL) is associated with increased circulating levels of multiple pro-inflammatory cytokines and chemokines, including IL-12, IFNγ, and TNFα, and elevated expression of IFNγ mRNA in lesional tissue such as the spleen and bone marrow. However, an immunological feature of VL patients is that their peripheral blood mononuclear cells (PBMCs) typically fail to respond to stimulation with leishmanial antigen. Unexpectedly, it was recently shown that Leishmania specific IFNγ, can readily be detected when a whole blood stimulation assay (WBA) is used. We sought to define the conditions that permit whole blood cells to respond to antigen stimulation, and clarify the biological role of the IFNγ found to be released by cells from VL patients. CD4+ T cells were found to be crucial for and the main source of the IFNγ production in Leishmania stimulated whole blood (WB) cultures. Complement, antibodies and red blood cells present in whole blood do not play a significant role in the IFNγ response. The IFNγ production was reduced by blockade of human leukocyte antigen (HLA)-DR, indicating that the response to leishmanial antigens observed in WB of active VL patients is a classical HLA- T cell receptor (TCR) driven reaction. Most importantly, blockade of IFNγ in ex-vivo splenic aspirate cultures demonstrated that despite the progressive nature of their disease, the endogenous IFNγ produced in patients with active VL serves to limit parasite growth.

Contribution of world health organization in the global acceptance of Ayurveda

Amongst the mandates of United Nations, health of mankind is the thrust area of UN through World Health Organization (WHO). Planning and execution of policies for mainstreaming of traditional medicines (TRM) of respective countries along with conventional system of medicine (allopathy), first in the country of origin followed by the international arena, is the priority agenda of operations of WHO. Within Indian context, WHO accorded prime focus to Ayurveda in its activities related to TRM.Sponsorship and encouragement of studies substantiating parameters of standardization, safety and efficacy of herbal medicines of Ayurveda are under chief consideration of WHO. In this review, several guidelines of WHO are summarized. Department of Ayurveda, Yoga and Naturopathy, Unani, Siddha and Homoeopathy (AYUSH), Central Council of Research in Ayurveda and Siddha and numerous other collaborative centers of WHO in India are assigned with several Appraisal Project Work (APW) and Direct Financial Cooperation (DFC) projects that will strengthen Ayurveda as evidence-based medicine for its global acceptance. Implementation of pharmacovigilance program in Ayurveda, publication of documents for rational use and initiatives to prepare consumer guidelines for appropriate use of Ayurvedic medicines are some other contributions of WHO toward advancement of Ayurveda at national as well as global level. Here, we suggest further exploration, interaction and interpretation of traditional knowledge in the light of contemporary core sciences and biomedical sciences that can pave the way for accreditation of Ayurveda worldwide as an established system of medicine.

A progressive review of Sandhana kalpana (Biomedical fermentation): An advanced innovative dosage form of Ayurveda.

Sandhana kalpana (biomedical fermented formulations) are one of the best dosage forms of Ayurveda in practice since thousands of years. In order to prepare these medicaments, certain sets of conditions are prearranged, which lead to fermentation. Thus, products bequeath with self-generated ethyl alcohol, which potentiate these preparations (Asava–Arishta), pharmaceutically and therapeutically. Commonly, medicinal and commercial components of these formulations are prompting many researchers to contribute in manufacturing, quality control, safety, and efficacy of these formulations. To cope up with this, literature related to Asava–Arishta has been surveyed from the Vedic period to recent publications of Government of India, ie, Ayurvedic Formulary of India, and presented briefly here. In this review paper, we have discussed pioneering facts such as nature and amount of carbohydrate, type of containers, optimum temperature, variety and relevance of initiator of fermentation, manufacturing, regulatory rules, and business aspects of Asava-Arishta. After going through this basic information, any academician or researcher may show a way to further strengthen this dosage form.

Pharmacovigilance: Boon for the safety and efficacy of ayuvedic formulations

Pharmacovigilance is a corrective process originating in pharmaco-epidemiology. The 1997 Erice Declaration, presented at the World Health Organisation, became the basis on which the concept was implemented internationally for conventional systems of medicine. The increasing international acceptance of Ayurveda, led regulators to implement a similar program for Ayurveda, particularly as some medical professionals, scientists and members of the public reported adverse reactions after taking Ayurvedic formulations. The World Health Organisation therefore persuaded the Department of AYUSH, Ministry of Health and Family Welfare, Government of India, to implement a pharmacovigilance program for Ayurveda, as a means to ensuring the safety and efficacy of Ayurvedic medicines. After a year of due diligence, the pharmacovigilance program was launched nationally on 29 September 2008. Since that time, Ayurveda, Siddha and Unani medicines have been monitored according to the provisions of a protocol prepared by the National Pharmacovigilance Resource Centre, IPGTRA, Jamnagar, and approved by Department of AYUSH. The program was reviewed, first, on 21st January 2009 by the National Pharmaco-vigilance Consultative Committee for ASU drugs (NPCC-ASU), and again, on 15 Feburary, 2010, when an evaluation meeting effectively rubber stamped the program. Among the outcomes of these meetings were several suggestions of measures to improve the program’s efficiency. Recent developments include the constitution of pharmacovigilance centers at all Ayurveda Teaching institutes and research centers.

Pharmaceutical study of Lauha Bhasma.

In the present research paper, the work done on pharmaceutical study of Lauha Bhasma conducted in the Department of Rasa Shastra under the postgraduate research programme is being presented. The pharmaceutical processing of Lauha Bhasma was performed by following samanya shodhana, vishesha shodhana and marana of Lauha. Under the process of marana, three specific pharmaceutical techniques were followed, viz. bhanupaka, sthalipaka and putapaka. During the putapaka process, an electric muffle furnace (EMF) was used. The temperature of puta was studied in two batches, viz. in Batch I, a temperature of 800°C was maintained whereas in Batch II, a temperature of 600°C was maintained. The purpose behind selecting two temperatures was to validate the process of marana of Lauha and to determine an ideal temperature for the preparation of Lauha Bhasma in EMF. It is found that after 20 puta at a temperature of 600°C, the Lauha Bhasma was prepared properly. The entire characteristic of Lauha Bhasma, like “pakwa jambu phala varna,” varitar, etc. was attained at 600°. At a temperature of 800°C, the process could not be carried out smoothly. The pellets turned very hard and brassy yellow in color. The desired color was attained only after decreasing the temperature in further puta.

Tumor necrosis factor alpha neutralization has no direct effect on parasite burden, but causes impaired IFN-γ production by spleen cells from human visceral leishmaniasis patients.

The pro-inflammatory cytokine tumor necrosis factor (TNF)-α has an important role in control of experimental Leishmania donovani infection. Less is known about the role of TNF-α in human visceral leishmaniasis (VL). Evidence for a protective role is primarily based on case reports of VL development in individuals treated with TNF-α neutralizing antibody. In this study, we have evaluated how TNF-α neutralization affects parasite replication and cytokine production in ex vivo splenic aspirates (SA) from active VL patients. The effect of TNF-α neutralization on cell mediated antigen specific responses were also evaluated using whole blood cultures. Neutralization of TNF-α did not affect parasite numbers in SA cultures. Interferon (IFN)-γ levels were significantly reduced, but interleukin (IL)-10 levels were unchanged in these cultures. Leishmania antigen stimulated SA produced significant TNF-α which suggests that TNF-α is actively produced in VL spleen. Further it stimulates IFN-γ production, but no direct effect on parasite replication.

A comparative review study of Sneha Kalpana (Paka) vis-a-vis liposome

Ayurvedic dosage forms are very exclusive in its pharmaceutics and therapeutics. Sneha Kalpana is a group of products of medicated taila and ghee, these drugs are treating very wide range of diseases among patients of all age groups. Liposomal system of drug delivery is a new invention in conventional system of medicine. This system is also covering a high degree of objective of therapeutics at different targets successfully. Probably, here is very distinctive similarity between these two on account of their aqueous and oleaginous origin. Most likely, these are two faces of same coin. A brief survey of literature is done here to explore possibilities of further investigation in benefit of mankind by applying wisdom of both fields together. In fact, this is a review paper based on certain hypothesis which may be established or rejected factually by further researches.

Inflammatory chemokines and their receptors in human visceral leishmaniasis: Gene expression profile in peripheral blood, splenic cellular sources and their impact on trafficking of inflammatory cells

&NA; Chemokines play an important role in determining cellular composition at inflammatory sites, and as such, influence disease outcome. In this study, we investigated the expression profile and splenic cellular source of various inflammatory chemokines and their receptors in human visceral leishmaniasis (VL). The expression of chemokines or their receptors was measured at the gene and protein level by employing real time qPCR and a cytometric bead array assay, respectively. In addition, the cellular source of chemokines and their receptors in the spleen was identified employing gene expression analyses in sequentially selected cell subsets. We identified elevated expression of CXCL10, CXCL9, CXCL8, and decreased CCL2 from VL patients. Further, we found reduced expression of the chemokine receptors CXCR1, CXCR2, CXCR3 and CCR2, but increased expression of CCR7 on VL PBMC, compared to endemic healthy controls. Additionally, splenic monocytes were found to be the major source of CXCL10, CXCL9 and CCR2, whereas T cells were the main source of CXCR3 and CCR7. We also report a strong association between plasma IFN‐&ggr; and CXCL‐10, CXCL‐9 levels. Enhanced parasite burden positively correlates with increased expression of CXCL10, CXCL9, IFN‐&ggr; and IL‐10. Overall our result indicates that VL patients have an elevated inflammatory chemokine milieu which correlated with disease severity. However, expression of their chemokine receptors was significantly impaired, which may have contributed to reduced frequencies of blood monocytes and neutrophils in peripheral blood. In contrast, enhanced expression of CCR7 was associated with increased numbers of activated T cells in circulation. These findings highlight the importance of chemokines for recruitment of various cell populations in VL, and the knowledge gained may help in global understandings of the complex interaction between chemokines and pathological processes, and therefore will contribute towards the design of novel chemokine based immunological therapies against VL. Graphical abstract Figure. No caption available. HighlightsD‐0 VL patients upregulate CXCL‐8, CXCL‐9, CXCL‐10 and CCR7 expression.VL patients at D‐0 down regulate CXCR1, CXCR2, CXCR3, CCR2 and CCL2 expression.Splenic monocytes are source of CXCL10, CXCL9, CCR2 and T cells for CXCR3, CCR7.Parasite load and plasma IFN‐&ggr; level positively correlates with CXCL‐10, CXCL‐9.% Monocytes, Neutrophils, WBC is reduced while lymphocytes are increased in VL.

Intellectual property rights and patents in perspective of Ayurveda

Ayurveda is getting its due recognition as a rationale system of medicine worldwide despite the fact that medical and scientific fraternity of the globe has very strong opposite opinion regarding safety and efficacy of Ayurvedic medicines. Meanwhile, provisions of Intellectual Property Rights under World Intellectual Property Organization (WIPO) and Patents have attracted many individuals and organizations to explore possibilities of commercial benefits with Ayurvedic traditional knowledge. Although rules are not favoring to grant a patent on prior published knowledge, biopiracy managed grant of Patent on knowledge of Ayurvedic medicinal plants which has been successfully checked with references of data base of Traditional Knowledge Digital Library (TKDL). Current provisions of the Patent law of India are obstructive in nature for getting patent on Ayurvedic medicines. If we have to invite researchers from basic science to ensure quality, safety and efficacy of Ayurvedic medicines, there is an urgent need to amend laws of patent with pragmatic promotional policies. This will encourage more patents on numerous pharmaceutical, nutraceutical and cosmaceutical products based on Ayurveda. As every action of todays world is based on economic criteria so why stakeholders of Ayurveda should be deprived of it. New inventions would drive acceptance of Ayurveda as a global system of medicine.