Adjuvant Properties of Thermal Component of Hyperthermia Enhanced Transdermal Immunization: Effect on Dendritic Cells

Hyperthermia enhanced transdermal (HET) immunization is a novel needle free immunization strategy employing application of antigen along with mild local hyperthermia (42°C) to intact skin resulting in detectable antigen specific Ig in serum. In the present study, we investigated the adjuvant effect of thermal component of HET immunization in terms of maturation of dendritic cells and its implication on the quality of the immune outcome in terms of antibody production upon HET immunization with tetanus toxoid (TT). We have shown that in vitro hyperthermia exposure at 42°C for 30 minutes up regulates the surface expression of maturation markers on bone marrow derived DCs. This observation correlated in vivo with an increased and accelerated expression of maturation markers on DCs in the draining lymph node upon HET immunization in mice. This effect was found to be independent of the antigen delivered and depends only on the thermal component of HET immunization. In vitro hyperthermia also led to enhanced capacity to stimulate CD4+ T cells in allo MLR and promotes the secretion of IL-10 by BMDCs, suggesting a potential for Th2 skewing of T cell response. HET immunization also induced a systemic T cell response to TT, as suggested by proliferation of splenocytes from immunized animal upon in vitro stimulation by TT. Exposure to heat during primary immunization led to generation of mainly IgG class of antibodies upon boosting, similar to the use of conventional alum adjuvant, thus highlighting the adjuvant potential of heat during HET immunization. Lastly, we have shown that mice immunized by tetanus toxoid using HET route exhibited protection against challenge with a lethal dose of tetanus toxin. Thus, in addition to being a painless, needle free delivery system it also has an immune modulatory potential

The diagnostic accuracy of diffusion weighted magnetic resonance (MR) imaging for discrimination of malignant from benign cervical lymphadenopathy in head and neck tumours using histopathology as the reference standard

Head and neck cancers accounts for maximum number of cancer cases in Indian hospital settings. Involvement of neck nodes is a very important prognostic factor of its outcome. Differentiation between benign and metastatic lymphadenopathy often presents a diagnostic challenge with conventional imaging techniques. Diffusion-weighted imaging (DWI) has emerged as a powerful non-invasive imaging technique that is capable of characterisation of these lesions as benign or malignant with the help of apparent diffusion coefficient (ADC) maps. Aim: The aim of this cross-sectional study was to determine the diagnostic accuracy of DWI to differentiate benign from malignant cervical lymph nodes in head and neck tumours, subsequently confirming the results using histopathology as the reference standard. Materials and Methods: The cross-sectional study was conducted on 60 patients of either age or sex with enlarged neck lymph nodes over a period of 2 years, subsequently these patients underwent DW MRI imaging followed by histopathology of either neck dissection specimen or core biopsy or US guided FNAC as a part of the study. Results: Out of 60 patients, 41(68.33 percent) cases came out as malignant and 19 (31.67 percent) cases came out as benign. The results obtained were 36 true positives, 4 false positives, 15 true negatives and 5 false negatives. The overall sensitivity of DWI for differentiating malignant from benign cervical lymphadenopathy was 87.80% with specificity of 78.95%. The positive predictive value and negative predictive value were 90.00% and 75.00% respectively. The best ADC threshold value for distinguishing benign and malignant nodes was 1.005 × 10-3 mm2/sec. Conclusion: DWI is an important tool to differentiate benign vs malignant lymphadenopathy and helps in guiding the clinician to treat these nodes accordingly

Production of subsurface drip-irrigated okra under different lateral spacings and irrigation frequencies

In this study, an experiment was conducted to investigate the optimum lateral spacing and irrigation frequency for subsurface drip irrigated okra in the semi-arid region of Haryana (India). Two lateral spacings (45 cm and 60 cm) and four irrigation frequencies (daily, after 1, 2 and 3 days) were selected to grow okra in the Kharif season of 2019 and 2020. The effect on soil water dynamics, growth parameters, efficiency and yield were assessed using equal amounts of water under all the treatments on the basis of pan evaporation. The results from the study depict that the overall soil moisture decreased laterally, but increased vertically downward with the increase in the irrigation interval. On the basis of soil water dynamics, plant growth parameters, efficiency and yield of okra, it was concluded that subsurface drip irrigation with daily irrigation at 45 cm lateral spacing gives better performance than all other treatments in sandy loam soil. The present study highlights the significance of proper irrigation frequency and lateral spacing for maximum production of okra. Using these guidelines, the income of okra growers/farmers in the semi-arid region may be increased by choosing the best frequency and lateral spacing of subsurface drip irrigation

Effect of IL-10 neutralization on production of IL-12p70, IL-12p40 and TNF-α by DCs pretreated with in vitro hyperthermia.

<p>DCs were incubated at 37°C (light gray) or 42°C (dark gray) for 30 minutes, and allowed to recover at 37°C for 6 hours. Then 0.1 µg/ml anti-IL-10 mAb or isotype control was added at the time of stimulation with 1 µg/ml LPS at 37°C for additional 22 hours. The supernatants were collected and the concentrations of IL-12p70, IL-12p40 and TNF-α were measured by ELISA. Data are shown as Mean ±SD of one typical experiment of three independent experiments.</p

Serum anti-TT Abs in mice primed by HET.

<p>Mice were immunized by soluble TT alone (i/m), TT with alum (i/m) or TT via HET. Unimmunized animal served as control. Booster of soluble TT (i/m) was given on Day 28 and mice were bled on week 5. Serum anti TT IgG1 (A1), IgG2a (A2) and IgG (A3) were estimated by ELISA. Recall response was evaluated by estimating the proliferative index by <i>in vitro</i> restimulation of splenocytes from immunized animals with TT antigen (B). Each dot represents individual animal and bars represent the geometric mean of each group.</p

Boosting upon HET immunization and toxin challenge.

<p>Mice were immunized via a single dose of HET patch or multiple doses of HET patch on day 0, 14, 28 and 42. The positive control was needle immunized with TT+alum on day 0 and 28. Toxin challenge was given one week after the completion of immunization schedule.</p