Maxadilan-simile expression in Nyssomyia neivai, a sandfly vector in an endemic region of Brazil, and its immunogenicity in patients with American tegumentary leishmaniasis

Abstract

BACKGROUND Maxadilan (Max) is a salivary component in the sandfly Lutzomyia longipalpis (Lutz & Neiva 1912), a vector of visceral leishmaniasis. Max has a powerful vasodilatory effect and is a candidate vaccine that has been tested in experimental leishmaniasis. Nyssomyia neivai (Pinto 1926) is a vector of the pathogen responsible for American tegumentary leishmaniasis (ATL) in Brazil.OBJECTIVE We searched for Max expression in Ny. neivai and for antibodies against Max in ATL patients.METHODS cDNA and protein were extracted from the cephalic segment, including salivary glands, of Ny. neivai and analysed by polymerase chain reaction, DNA sequencing, and blotting assays. The results were compared with data obtained from Lu. longipalpis samples. We quantified antibodies against Max in serum samples from 41 patients with ATL (31 and 10 with the cutaneous and mucocutaneous forms, respectively) and 63 controls from the endemic northeastern region of São Paulo state, using enzyme-linked immunosorbent assay.FINDINGS Recognition of a Max-simile peptide by specific antibodies confirmed expression of a Max sequence in Ny. neivai (GenBank EF601123.1). Compared to controls, patients with ATL presented higher levels of antibodies against Max (p = 0.004); 24.4% of the patients with ATL and 3.2% of the controls presented anti-Max levels above the cutoff index (p = 0.014). The anti-Max levels were not associated with the specific clinical form of ATL, leishmanin skin test response, absence or presence of amastigotes in histopathologic exam, results of indirect immunofluorescence testing for leishmaniasis, or duration of cutaneous form disease.MAIN CONCLUSION High serum anti-Max levels did not protect patients against ATL, but confirmed previous natural exposure to Ny. neivai bites in this ATL endemic region.

Pemphigus foliaceus and sand fly bites: assessing the humoral immune response to the salivary proteins maxadilan and LJM11

“…The VL group presented higher titres compared with the PF, PFR and HC groups (Kruskall–Wallis followed by Dunn's test: P = 0·0039, P = 0·0008 and P < 0·0001, respectively) (Figure 1b). Interestingly, the TL, PF and PFR titres were similar, confirming that all had been bitten by Nyssomyia neivai – the vector of TL in NSPS 4,5. Moreover, the PF titres were higher compared with the HC titres ( P = 0·0071), but similar to the PFR titres.…”

“…Interestingly, the TL, PF and PFR titres were similar, confirming that all had been bitten by Nyssomyia neivaithe vector of TL in NSPS. 4,5 Moreover, the PF titres were higher compared with the HC titres (P = 0Á0071), but similar to the PFR titres.…”

“…Lerner, 3 and recombinant LJM11 (rLJM11) was produced in Escherichia coli cells by using the AAS05318Á1 sequence (GenBank NCBI) (WatsonBio LLC, Houston, TX, USA) (Figure 1a). Because patients with TL and VL had certainly been bitten by sand flies, to standardize the in-house ELISA for rMax and rLJM11, serum samples from five patients with TL with known high anti-rMax titres, as reported previously, 4 and from five patients with VL were tested. As controls, serum samples from five HCs without medical records of leishmaniasis were used.…”

RNA-sequencing of the Nyssomyia neivai sialome: a sand fly-vector from a Brazilian endemic area for tegumentary leishmaniasis and pemphigus foliaceus

“…Maxadilan has its own branch and, JAV08462.1 from N. neivai was the closest relative to Maxadilan with 37.5% identity and 56.2% similarity suggesting that N. neivai JAV08462.1 (Fig. 4 B) may have preserved its pharmacological properties 52 . N. neivai JAV08462.1 represents the sixth most abundant member with 6.44% of the maxadilan-like family abundance.…”

“…Sand fly salivary proteins have been associated with endemic PF pathogenesis in Brazil and Tunisia 10 – 12 , 52 , 80 – 82 . Screening of sera from pemphigus foliaceus patients from NSPS antibodies against Lu.…”