Neem leaf glycoprotein reverses tumor-induced and age-associated thymic involution to maintain peripheral CD8+ T cell pool

Immunotherapy. 2020 Aug;12(11):799-818. doi: 10.2217/imt-2019-0168. Epub 2020 Jul 22.

Abstract

Aim: As tumor causes atrophy in the thymus to target effector-T cells, this study is aimed to decipher the efficacy of neem leaf glycoprotein (NLGP) in tumor- and age-associated thymic atrophy. Materials & methods: Different thymus parameters were studied using flow cytometry, reverse transcriptase PCR and immunocyto-/histochemistry in murine melanoma and sarcoma models. Results: Longitudinal NLGP therapy in tumor hosts show tumor-reduction along with significant normalization of thymic alterations. NLGP downregulates intrathymic IL-10, which eventually promotes Notch1 to rescue blockade in CD25+CD44+c-Kit+DN2 to CD25+CD44-c-Kit-DN3 transition in T cell maturation and suppress Ikaros/IRF8/Pu.1 to prevent DN2-T to DC differentiation in tumor hosts. The CD5intTCRαβhigh DP3 population was also increased to endorse CD8+ T cell generation. Conclusion: NLGP rescues tumor-induced altered thymic events to generate more effector T cells to restrain tumor.

Keywords: IL-10; NLGP; dendritic cells; thymic atrophy; thymus; tumor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging / physiology*
  • Animals
  • Antineoplastic Agents, Phytogenic / therapeutic use*
  • Azadirachta / immunology
  • Blood Circulation
  • CD8-Positive T-Lymphocytes / drug effects
  • CD8-Positive T-Lymphocytes / immunology*
  • Disease Models, Animal
  • Glycoproteins / isolation & purification
  • Glycoproteins / therapeutic use*
  • Humans
  • Melanoma, Experimental
  • Mice
  • Mice, Inbred C57BL
  • Neoplasms, Experimental / therapy*
  • Plant Leaves
  • Plant Proteins / isolation & purification
  • Plant Proteins / therapeutic use*
  • Sarcoma 180
  • Thymus Gland / drug effects*
  • Thymus Gland / pathology

Substances

  • Antineoplastic Agents, Phytogenic
  • Glycoproteins
  • Plant Proteins