Rhipicephalus microplus cystatin as a potential cross-protective tick vaccine against Rhipicephalus appendiculatus

Autor(es):Mostrar menos -

Parizi, Luis Fernando ^[1] ; Rangel, Carolina Konrdorfer ^[1] ; Sabadin, Gabriela Alves ^[1] ; Saggin, Bianca Fagundes ^[1] ; Kiio, Irene ^{[2, 3]} ; Xavier, Marina Amaral ^[1] ; Matos, Renata da Silva ^[4] ; Camargo-Mathias, Maria Izabel ^[4] ; Seixas, Adriana ^{[5, 6]} ; Konnai, Satoru ^[7] ; Ohashi, Kazuhiko ^[7] ; Githaka, Naftaly Wang'ombe ^[2] ; Vaz Jr, Itabajara da Silva

Afiliação do(s) autor(es)

^[1] Univ Fed Rio Grande do Sul, Ctr Biotecnol, Ave Bento Goncalves 9500, BR-91501970 Porto Alegre, RS - Brazil

^[2] ILRI, POB 30709-00100, Nairobi - Kenya

^[3] Univ Nairobi, Sch Med, Dept Biochem, POB 30197-00100, Nairobi - Kenya

^[4] UNESP Univ Estadual Paulista, Inst Biociencias, Dept Biol, Rio Claro, SP - Brazil

^[5] Inst Nacl Ciencia & Tecnol Entomol Mol, Rio De Janeiro - Brazil

^[6] Univ Fed Ciencias Saude Porto Alegre, Dept Farmacociencias, Rua Sarmento Leite 245, BR-90050170 Porto Alegre, RS - Brazil

^[7] Hokkaido Univ, Grad Sch Vet Med, Dept Dis Control, Lab Infect Dis, Sapporo, Hokkaido 0600818 - Japan

• Tipo de documento: Artigo Científico
• Fonte: TICKS AND TICK-BORNE DISEASES; v. 11, n. 3 MAY 2020.
• Citações Web of Science: 0

Resumo

Rhipicephalus appendiculatus, the brown ear tick, is an important disease vector of livestock in eastern, central and southern Africa. Rhipicephalus appendiculatus acaricide resistance requires the search for alternative methods for its control. Cystatins constitute a superfamily of cysteine peptidase inhibitors vital for tick blood feeding and development. These inhibitors were proposed as antigens in anti-tick vaccines. In this work, we applied structural and biochemical approaches to characterize a new cystatin named R. appendiculatus cystatin 2a (Racys2a). Structural modeling showed that this new protein possesses characteristic type 2 cystatin motifs, besides conservation of other structural patterns along the protein. Peptidase inhibitory assays with recombinant Racys2a showed modulation of tick and host cathepsins involved in blood digestion and immune system responses, respectively. A heterologous tick challenge with R. appendiculatus in rabbits immunized with recombinant Rhipicephalus microplus cystatin 2c (rBmcys2c) was performed to determine cross-reactivity. Histological staining showed that rBmcys2c vaccination caused damage to the gut, salivary gland and ovary tissues in R. appendiculatus. Furthermore, cystatin vaccine reduced the number of fully engorged adult females in 11.5 %. Consequently, strategies to increase the protection rate are necessary, including the selection of two or more antigens to compose a vaccine cocktail. (AU)

• Processo FAPESP: 14/13143-7 - Estudo morfofisiológico das glândulas salivares, singânglio, órgão de gene e ovários de fêmeas ingurgitadas de Rhipicephalus sanguineus (Latreille, 1806) (Acari: Ixodidae) tratadas com diferentes concentrações de timol
• Beneficiário: Renata da Silva Matos
• Modalidade de apoio: Bolsas no Brasil - Doutorado