Novel Presentation of Major Histocompatibility Complex Class II Deficiency with Hemophagocytic Lymphohistiocytosis.

Purpose: Major histocompatibility complex (MHC) class II deficiency is one of the combined immune deficiency disorders caused by defects in the MHC class II regulatory genes leading to abnormal T cells development and function. Therefore, patients mainly present with increased susceptibility to infections, diarrhea, and failure to thrive. In this report, we present one MHC class II deficient patient with a novel presentation with Hemophagocytic Lymphohistiocytosis (HLH).

Preerythrocytic Vaccine Antigens Enhance Sterile Protection in Mice Induced by Circumsporozoite Protein.

Preerythrocytic vaccines prevent malaria by targeting parasites in the clinically silent sporozoite and liver stages and preventing progression to the virulent blood stages. The leading preerythrocytic vaccine, RTS,S/AS01E (Mosquirix), entered implementation programs in 2019 and targets the major sporozoite surface antigen, circumsporozoite protein (CSP). However, in phase III clinical trials, RTS,S conferred partial protection with limited durability, indicating a need to improve CSP-based vaccination.

The Form of an Antigen and Its Molecular Context Do Matter: Infectious versus Attenuated Plasmodium Sporozoites.

The physicochemical properties of an antigen (Ag) influence the type, specificity, as well as duration of emerging immune responses. Like immune responses arising to nominal protein Ags, reactivities to protozoan parasites, Plasmodium falciparum and P. berghei, the causative agents of human and mouse malaria, respectively, are shaped by the form of the parasite.