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Visceral leishmaniasis (VL) is a severe and often fatal form of leishmaniasis caused by Leishmania donovani in the Indian sub-continent. Post Kala-azar Dermal Leishmaniasis (PKDL) is a late cutaneous manifestation of VL, typically occurring after apparent cure of VL, but sometimes even without a prior history of VL in India. PKDL serves as a significant yet neglected reservoir of infection and plays a crucial role in the transmission of the disease, posing a serious threat to the VL elimination program in the Indian sub-continent. Therefore, the eradication of PKDL should be a priority within the current VL elimination program aimed at achieving a goal of less than 1 case per 10,000 in the population at the district or sub-district levels of VL endemic areas. To accomplish this, a comprehensive understanding of the pathogenesis of PKDL is essential, as well as developing strategies for disease management. This review provides an overview of the current status of diagnosis and treatment options for PKDL, highlighting our current knowledge of the immune responses underlying disease development and progression. Additionally, the review discusses the impact of PKDL on elimination programs and propose strategies to overcome this challenge and achieve the goal of elimination. By addressing the diagnostic and therapeutic gaps, optimizing surveillance and control measures, and implementing effective intervention strategies, it is possible to mitigate the burden of PKDL and facilitate the successful elimination of VL in the Indian sub-continent. [ABSTRACT FROM AUTHOR]

Chronic helminth infections are known to be associated with the modulation of antigen-specific T-cell responses. Strongyloides stercoralis infection is characterized by the downmodulation of antigen-specific Th1 and Th17 responses and the upregulation of Th2 and Th9 responses. Immune homeostasis is partially maintained by negative regulators of T-cell activation, cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and programmed death 1 (PD-1), which dampen effector responses during chronic infections. However, their roles in S. stercoralis infection are yet to be defined. Therefore, we sought to determine the role of CTLA-4 and PD-1 in regulating CD4 + and CD8 + T-cell responses and examined the frequencies of monofunctional and dual functional Th1/T cytotoxic type 1 (Tc1), Th17/Tc17, Th2/Tc2, and Th9/Tc9 cells in S. stercoralis infection in 15 infected individuals stimulated with parasite antigen following CTLA-4 or PD-1 blockade. Our data reveal that CTLA-4 or PD-1 blockade results in significantly enhanced frequencies of monofunctional and dual functional Th1/Tc1 and Th17/Tc17 cells and, in contrast, diminishes the frequencies of monofunctional and dual functional Th2/Tc2 and Th9/Tc9 cells with parasite antigen stimulation in whole-blood cultures. Thus, we demonstrate that CTLA-4 and PD-1 limit the induction of particular T-cell subsets in S. stercoralis infection, which suggests the importance of CTLA-4 and PD-1 in immune modulation in a chronic helminth infection., (Copyright © 2019 American Society for Microbiology.)

Immunology is a relatively new specialty. Ironically, the immune system impacts every physiological system in the body, but yet most textbooks of physiology do not include any functional aspects of the immune system. Indeed, with the exception of early descriptions of anaphylaxis and allergy, the majority of immune studies were focused on either the anatomy of lymph nodes and spleen, or of course on protection from microorganisms. The concept of autoimmunity is even newer and the first textbook on autoimmune disease was not published until 1963. For the past 50 years however, autoimmunity has virtually exploded from a field populated by a few, to recognition that autoimmune diseases can affect more than 10% of the population. There are many people that have contributed to this information explosion and the Journal of Autoimmunity devotes specific issues in recognition of the select few scientists that have contributed in a way that impacts not only their research peers, but also, and more importantly, the patients who suffer from autoimmune disease. Abul Abbas is one such individual. Abul is known not only for his outstanding research, but for his role in teaching and public service. His own scientific work is extraordinary and his impact is felt throughout the world. In this special issue a number of Abul's colleagues have specifically written papers to honor this unique individual. It is an extraordinary honor to be chosen for a special issue of a journal in recognition of one's career., (Copyright © 2013 Elsevier Ltd. All rights reserved.)