Abstract
In developing countries, people remain infected with protozoan and helminths parasite contributing to death and economic loss. Toll-like receptors (TLRs) family is considered one of the most major pattern recognition receptors found to be concerned in innate immunity and expressed intracellularly as well as on cell surfaces. They play an essential function in the various protozoans and helminths' ability to activate the host immune system response. These were engaged in producing cytokines and chemokines to promote phagocytosis and the killing of parasites. TLRs have negative regulation strategies to decrease the production of pro-inflammatory cytokines to reduces excessive pathology and reduce tissue damage caused by unregulated TLR activation. The main achievements findings made on the strategies of TLRs negative regulation mediated host response against protozoan and helminthic parasitic infections have been collected using many databases and the research published papers in indexed medical journals. Clarification of the relationship of host-parasites with the TLR pathway would enhance the management method of pathogens immunotherapy. Research in these fields have informed the production of new generation of therapeutics so that science in this field will have a promising future. In this review, we discuss the relationships between most pathogens and the strategies of TLRs to manage infectious diseases in the host immune regulatory network. Furthermore, the promising role that TLRs play in all parasite infections and therapeutic control strategies will also be stressed. Further studies are required to check for interplay strategies that control negative regulation that will provide new guidelines for the therapy of several crosstalk pathogens.