@article {140659, title = {Immunogenicity of SARS-CoV-2 vaccines BBV152 (COVAXIN{\textregistered}) and ChAdOx1 nCoV-19 (COVISHIELD{\texttrademark}) in seronegative and seropositive individuals in India: a multicentre, nonrandomised observational study.}, journal = {Lancet Reg Health Southeast Asia}, volume = {22}, year = {2024}, month = {2024 Mar}, pages = {100361}, abstract = {

BACKGROUND: There are limited global data on head-to-head comparisons of vaccine platforms assessing both humoral and cellular immune responses, stratified by pre-vaccination serostatus. The COVID-19 vaccination drive for the Indian population in the age group 18-45 years began in April 2021 when seropositivity rates in the general population were rising due to the delta wave of COVID-19 pandemic during April-May\ 2021.

METHODS: Between June 30, 2021, and Jan 28, 2022, we enrolled 691 participants in the age group 18-45 years across four clinical sites in India. In this non-randomised and laboratory blinded study, participants received either two doses of Covaxin{\textregistered} (4 weeks apart) or two doses of Covishield{\texttrademark} (12 weeks apart) as per the national vaccination policy. The primary outcome was the seroconversion rate and the geometric mean titre (GMT) of antibodies against the SARS-CoV-2 spike and nucleocapsid proteins post two doses. The secondary outcome was the frequency of cellular immune responses pre- and post-vaccination.

FINDINGS: When compared to pre-vaccination baseline, both vaccines elicited statistically significant seroconversion and binding antibody levels in both seronegative and seropositive individuals. In the per-protocol cohort, Covishield{\texttrademark} elicited higher antibody responses than Covaxin{\textregistered} as measured by seroconversion rate (98.3\% vs 74.4\%, p\ \<\ 0.0001 in seronegative individuals; 91.7\% vs 66.9\%, p\ \<\ 0.0001 in seropositive individuals) as well as by anti-spike antibody levels against the ancestral strain (GMT 1272.1 vs 75.4 binding antibody units/ml [BAU/ml], p\ \<\ 0.0001 in seronegative individuals; 2089.07 vs 585.7 BAU/ml, p\ \<\ 0.0001 in seropositive individuals). As participants at all clinical sites were not recruited at the same time, site-specific immunogenicity was impacted by the timing of vaccination relative to the delta and omicron waves. Surrogate neutralising antibody responses against variants-of-concern including delta and omicron was higher in Covishield{\texttrademark} recipients than in Covaxin{\textregistered} recipients; and in seropositive than in seronegative individuals after both vaccination and asymptomatic infection (omicron variant). T cell responses are reported from only one of the four site cohorts where the vaccination schedule preceded the omicron wave. In seronegative individuals, Covishield{\texttrademark} elicited both CD4+ and CD8+ spike-specific cytokine-producing T cells whereas Covaxin{\textregistered} elicited mainly CD4+ spike-specific T cells. Neither vaccine showed significant post-vaccination expansion of spike-specific T cells in seropositive individuals.

INTERPRETATION: Covishield{\texttrademark} elicited immune responses of higher magnitude and breadth than Covaxin{\textregistered} in both seronegative individuals and seropositive individuals, across cohorts representing the pre-vaccination immune history of most of the vaccinated Indian population.

FUNDING: Corporate social responsibility (CSR) funding from Hindustan Unilever Limited (HUL) and Unilever India Pvt. Ltd. (UIPL).

}, issn = {2772-3682}, doi = {10.1016/j.lansea.2024.100361}, author = {Asokan, Mangaiarkarasi S and Joan, Roshni Florina and Babji, Sudhir and Dayma, Girish and Nadukkandy, Prajitha and Subrahmanyam, Vinutha and Pandey, Archana and Malagi, Girish and Arya, Pooja and Mahajan, Vibhuti and Bhavikatti, Jayateerth and Pawar, Ketakee and Thorat, Aishwarya and Shah, Priyanki and Goud, Ramakrishna B and Roy, Bishnudeo and Rajukutty, Shon and Immanuel, Sushil and Agarwal, Dhiraj and Saha, Sankhanil and Shivaraj, Akshatha and Panikulam, Patricia and Shome, Rajeshwari and Gulzar, Shah-E-Jahan and Sharma, Anusmrithi U and Naik, Ajinkya and Talashi, Shruti and Belekar, Madhuri and Yadav, Ritu and Khude, Poornima and V, Mamatha and Shivalingaiah, Sudarshan and Deshmukh, Urmila and Bhise, Chinmayee and Joshi, Manjiri and Inbaraj, Leeberk Raja and Chandrasingh, Sindhulina and Ghose, Aurnab and Jamora, Colin and Karumbati, Anandi S and Sundaramurthy, Varadharajan and Johnson, Avita and Ramesh, Naveen and Chetan, Nirutha and Parthiban, Chaitra and Ahmed, Asma and Rakshit, Srabanti and Adiga, Vasista and D{\textquoteright}Souza, George and Rale, Vinay and George, Carolin Elizabeth and John, Jacob and Kawade, Anand and Chaturvedi, Akanksha and Raghunathan, Anu and Dias, Mary and Bhosale, Anand and Raghu, Padinjat and Shashidhara, L S and Vyakarnam, Annapurna and Bal, Vineeta and Kang, Gagandeep and Mayor, Satyajit} } @article {137335, title = {Niacinamide enhances cathelicidin mediated SARS-CoV-2 membrane disruption.}, journal = {Front Immunol}, volume = {14}, year = {2023}, month = {2023}, pages = {1255478}, abstract = {

The continual emergence of SARS-CoV-2 variants threatens to compromise the effectiveness of worldwide vaccination programs, and highlights the need for complementary strategies for a sustainable containment plan. An effective approach is to mobilize the body{\textquoteright}s own antimicrobial peptides (AMPs), to combat SARS-CoV-2 infection and propagation. We have found that human cathelicidin (LL37), an AMP found at epithelial barriers as well as in various bodily fluids, has the capacity to neutralise multiple strains of SARS-CoV-2. Biophysical and computational studies indicate that LL37{\textquoteright}s mechanism of action is through the disruption of the viral membrane. This antiviral activity of LL37 is enhanced by the hydrotropic action of niacinamide, which may increase the bioavailability of the AMP. Interestingly, we observed an inverse correlation between LL37 levels and disease severity of COVID-19 positive patients, suggesting enhancement of AMP response as a potential therapeutic avenue to mitigate disease severity. The combination of niacinamide and LL37 is a potent antiviral formulation that targets viral membranes of various variants and can be an effective strategy to overcome vaccine escape.

}, keywords = {Antimicrobial Cationic Peptides, Antiviral Agents, Cathelicidins, COVID-19, Humans, Niacinamide, SARS-CoV-2}, issn = {1664-3224}, doi = {10.3389/fimmu.2023.1255478}, author = {Bhatt, Tanay and Dam, Binita and Khedkar, Sneha Uday and Lall, Sahil and Pandey, Subhashini and Kataria, Sunny and Ajnabi, Johan and Gulzar, Shah-E-Jahan and Dias, Paul M and Waskar, Morris and Raut, Janhavi and Sundaramurthy, Varadharajan and Vemula, Praveen Kumar and Ghatlia, Naresh and Majumdar, Amitabha and Jamora, Colin} } @article {117962, title = {Initiation of wound healing is regulated by the convergence of mechanical and epigenetic cues.}, journal = {PLoS Biol}, volume = {20}, year = {2022}, month = {2022 Sep}, pages = {e3001777}, abstract = {

Wound healing in the skin is a complex physiological process that is a product of a cell state transition from homeostasis to repair. Mechanical cues are increasingly being recognized as important regulators of cellular reprogramming, but the mechanism by which it is translated to changes in gene expression and ultimately cellular behavior remains largely a mystery. To probe the molecular underpinnings of this phenomenon further, we used the down-regulation of caspase-8 as a biomarker of a cell entering the wound healing program. We found that the wound-induced release of tension within the epidermis leads to the alteration of gene expression via the nuclear translocation of the DNA methyltransferase 3A (DNMT3a). This enzyme then methylates promoters of genes that are known to be down-regulated in response to wound stimuli as well as potentially novel players in the repair program. Overall, these findings illuminate the convergence of mechanical and epigenetic signaling modules that are important regulators of the transcriptome landscape required to initiate the tissue repair process in the differentiated layers of the epidermis.

}, keywords = {Biomarkers, Caspase 8, Cues, Epigenesis, Genetic, Wound Healing}, issn = {1545-7885}, doi = {10.1371/journal.pbio.3001777}, author = {Bhatt, Tanay and Dey, Rakesh and Hegde, Akshay and Ketkar, Alhad Ashok and Pulianmackal, Ajai J and Deb, Ashim P and Rampalli, Shravanti and Jamora, Colin} } @article {117964, title = {Snail maintains the stem/progenitor state of skin epithelial cells and carcinomas through the autocrine effect of matricellular protein Mindin.}, journal = {Cell Rep}, volume = {40}, year = {2022}, month = {2022 Sep 20}, pages = {111390}, abstract = {

Preservation of a small population of cancer stem cells (CSCs) within a heterogeneous carcinoma serves as a paradigm to understand how select cells in a tissue maintain their undifferentiated status. In both embryogenesis and cancer, Snail has been correlated with stemness, but the molecular underpinning of this phenomenon remains largely ill-defined. In models of cutaneous squamous cell carcinoma (cSCC), we discovered a non-epithelial-mesenchymal transition function for the transcription factor Snail in maintaining the stemness of epidermal keratinocytes. Snail-expressing cells secrete the matricellular protein Mindin, which functions in an autocrine fashion to activate a Src-STAT3 pathway to reinforce their stem/progenitor phenotype. This pathway is activated by the engagement of Mindin with the leukocyte-specific integrin, CD11b (ITGAM), which is also unexpectedly expressed by epidermal keratinocytes. Interestingly, disruption of this signaling module in human cSCC attenuates tumorigenesis, suggesting that targeting Mindin would be a promising therapeutic approach to hinder cancer recurrence.

}, keywords = {Carcinoma, Squamous Cell, Cell Line, Tumor, Epithelial Cells, Extracellular Matrix Proteins, Humans, Integrins, Neoplasm Proteins, Neoplasm Recurrence, Local, Neoplastic Stem Cells, Skin Neoplasms, Snail Family Transcription Factors}, issn = {2211-1247}, doi = {10.1016/j.celrep.2022.111390}, author = {Badarinath, Krithika and Dam, Binita and Kataria, Sunny and Zirmire, Ravindra K and Dey, Rakesh and Kansagara, Gaurav and Ajnabi, Johan and Hegde, Akshay and Singh, Randhir and Masudi, Tafheem and Sambath, Janani and Sachithanandan, Sasikala P and Kumar, Prashant and Gulyani, Akash and He, You-Wen and Krishna, Sudhir and Jamora, Colin} } @article {100557, title = {Isolation and Quantification of Mouse γδT-cells and .}, journal = {Bio Protoc}, volume = {11}, year = {2021}, month = {2021 Sep 05}, pages = {e4148}, abstract = {

The skin plays an important role in protecting the body from pathogens and chemicals in the external environment. Upon injury, a healing program is rapidly initiated and involves extensive intercellular communication to restore tissue homeostasis. The deregulation of this crosstalk can lead to abnormal healing processes and is the foundation of many skin diseases. A relatively overlooked cell type that nevertheless plays critical roles in skin homeostasis, wound repair, and disease is the dendritic epidermal T cells (DETCs), which are also called γδT-cells. Given their varied roles in both physiological and pathological scenarios, interest in the regulation and function of DETCs has substantially increased. Moreover, their ability to regulate other immune cells has garnered substantial attention for their potential role as immunomodulators and in immunotherapies. In this article, we describe a protocol to isolate and culture DETCs and analyse them within the skin. These approaches will facilitate the investigation of their crosstalk with other cutaneous cells and the mechanisms by which they influence the status of the skin. Graphic abstract: Overall workflow to analyse DETCs and .

}, issn = {2331-8325}, doi = {10.21769/BioProtoc.4148}, author = {Rana, Isha and Badarinath, Krithika and Zirmire, Ravindra K and Jamora, Colin} } @article {74434, title = {Sustained Secretion of the Antimicrobial Peptide S100A7 Is Dependent on the Downregulation of Caspase-8.}, journal = {Cell Rep}, volume = {29}, year = {2019}, month = {2019 Nov 26}, pages = {2546-2555.e4}, abstract = {

Antimicrobial peptides (AMPs) are the body{\textquoteright}s natural innate immune defense against a spectrum of pathogens and can also modulate cell proliferation, chemotaxis, angiogenesis, wound healing, and immune cell activity. Harnessing these diverse functions for prophylactic use is contingent upon understanding the regulatory mechanisms governing their unconventional secretion from cells. Analysis of the secretion of S100A7 (Psoriasin), an abundant AMP stored in differentiated keratinocytes of the skin, has revealed an unexpected biphasic secretory response to bacterial exposure. The core components regulating S100A7 secretion are NFκB/p38MAPK, caspase-1, and interleukin (IL)-1α. The initial activation of this core machinery is mediated by Toll-like receptor signaling, whereas the chronic response is mediated by Caspase-8 downregulation. Interestingly, there is a concomitant downregulation of Caspase-8 in inflammatory skin diseases wherein S100A7 is constitutively released. These results highlight the potential of targeting these components to control the release of AMPs from the skin in both homeostatic and disease conditions.

}, issn = {2211-1247}, doi = {10.1016/j.celrep.2019.10.090}, author = {Bhatt, Tanay and Bhosale, Aishwarya and Bajantri, Bhavya and Mathapathi, Mruthyunjaya Swamy and Rizvi, Abrar and Scita, Giorgio and Majumdar, Amitabha and Jamora, Colin} } @article {36106, title = {Interactions Between Epidermal Keratinocytes, Dendritic Epidermal T-Cells, and Hair Follicle Stem Cells.}, journal = {Methods Mol Biol}, year = {2018}, month = {2018 Jun 13}, abstract = {

The interplay of immune cells and stem cells in maintaining skin homeostasis and repair is an exciting new frontier in cutaneous biology. With the growing appreciation of the importance of this new crosstalk comes the requirement of methods to interrogate the molecular underpinnings of these leukocyte-stem cell interactions. Here we describe how a combination of FACS, cellular coculture assays, and conditioned media treatments can be utilized to advance our understanding of this emerging area of intercellular communication between immune cells and stem cells.

}, issn = {1940-6029}, doi = {10.1007/7651_2018_155}, author = {Badarinath, Krithika and Dutta, Abhik and Hegde, Akshay and Pincha, Neha and Gund, Rupali and Jamora, Colin} } @article {32022, title = {PAI1 mediates fibroblast-mast cell interactions in skin fibrosis.}, journal = {J Clin Invest}, year = {2018}, month = {2018 Mar 26}, abstract = {

Fibrosis is a prevalent pathological condition arising from the chronic activation of fibroblasts. This activation results from the extensive intercellular crosstalk mediated by both soluble factors and direct cell-cell connections. Prominent among these are the interactions of fibroblasts with immune cells, in which the fibroblast-mast cell connection, although acknowledged, is relatively unexplored. We have used a Tg mouse model of skin fibrosis, based on expression of the transcription factor Snail in the epidermis, to probe the mechanisms regulating mast cell activity and the contribution of these cells to this pathology. We have discovered that Snail-expressing keratinocytes secrete plasminogen activator inhibitor type 1 (PAI1), which functions as a chemotactic factor to increase mast cell infiltration into the skin. Moreover, we have determined that PAI1 upregulates intercellular adhesion molecule type 1 (ICAM1) expression on dermal fibroblasts, rendering them competent to bind to mast cells. This heterotypic cell-cell adhesion, also observed in the skin fibrotic disorder scleroderma, culminates in the reciprocal activation of both mast cells and fibroblasts, leading to the cascade of events that promote fibrogenesis. Thus, we have identified roles for PAI1 in the multifactorial program of fibrogenesis that expand its functional repertoire beyond its canonical role in plasmin-dependent processes.

}, issn = {1558-8238}, doi = {10.1172/JCI99088}, author = {Pincha, Neha and Hajam, Edries Yousaf and Badarinath, Krithika and Batta, Surya Prakash Rao and Masudi, Tafheem and Dey, Rakesh and Andreasen, Peter and Kawakami, Toshiaki and Samuel, Rekha and George, Renu and Danda, Debashish and Jacob, Paul Mazhuvanchary and Jamora, Colin} }