Antimicrobial Peptides: Differential Expression during Development and Potential Involvement in Vector Interaction with Microbiota and .

Antimicrobial peptides (AMPs) are produced to control bacteria, fungi, protozoa, and other infectious agents. Sand fly larvae develop and feed on a microbe-rich substrate, and the hematophagous females are exposed to additional pathogens. We focused on understanding the role of the AMPs attacin (Att), cecropin (Cec), and four defensins (Def1, Def2, Def3, and Def4) in the main vector of visceral leishmaniasis in the Americas.

TGF-β Has a Role in Survival in the Vector.

Despite the increasing number of studies concerning insect immunity, immune responses in the presence of infection has not been widely investigated. The few available studies analyzed the role of the Toll and IMD pathways involved in response against and microbial infections. Nevertheless, effector molecules responsible for controlling sand fly infections have not been identified.

Leishmania, microbiota and sand fly immunity.

In this review, we explore the state-of-the-art of sand fly relationships with microbiota, viruses and Leishmania, with particular emphasis on the vector immune responses. Insect-borne diseases are a major public health problem in the world. Phlebotomine sand flies are proven vectors of several aetiological agents including viruses, bacteria and the trypanosomatid Leishmania, which are responsible for diseases such as viral encephalitis, bartonellosis and leishmaniasis, respectively.

Identification of Secreted Proteins Involved in Nonspecific dsRNA-Mediated Lutzomyia longipalpis LL5 Cell Antiviral Response.

Hematophagous insects transmit infectious diseases. Sand flies are vectors of leishmaniasis, but can also transmit viruses. We have been studying immune responses of , the main vector of visceral leishmaniasis in the Americas.

Alternative splicing originates different domain structure organization of Lutzomyia longipalpis chitinases.

BACKGROUND The insect chitinase gene family is composed by more than 10 paralogs, which can codify proteins with different domain structures. In Lutzomyia longipalpis, the main vector of visceral leishmaniasis in Brazil, a chitinase cDNA from adult female insects was previously characterized. The predicted protein contains one catalytic domain and one chitin-binding domain (CBD).

Cloning, expression and characterisation of an HtrA-like serine protease produced in vivo by Mycobacterium leprae.

Members of the high temperature requirement A (HtrA) family of chaperone proteases have been shown to play a role in bacterial pathogenesis. In a recent report, we demonstrated that the gene ML0176, which codes for a predicted HtrA-like protease, a gene conserved in other species of mycobacteria, is transcribed by Mycobacterium leprae in human leprosy lesions. In the present study, the recombinant ML0176 protein was produced and its enzymatic properties investigated.

Mycobacterium leprae induces insulin-like growth factor and promotes survival of Schwann cells upon serum withdrawal.

Peripheral nerve lesions are considered the most relevant symptoms of leprosy, a chronic infectious disease caused by Mycobacterium leprae. The strategies employed by M. leprae to infect and multiply inside Schwann cells (SCs), however, remain poorly understood.

Expression analysis of proteases of Mycobacterium leprae in human skin lesions.

Proteases are commonly involved in bacterial pathogenesis and their inhibition has represented a successful therapeutic approach to treat infectious diseases. However, there is little information on the role of proteases in the pathogenesis of Mycobacteria. Five of these genes, three coding for putative secreted proteases, were selected in the present study to investigate their expression in Mycobacterium leprae isolated from skin biopsies of multibacillary leprosy patients.