Hemocyte types and total and differential counts in unparasitized and parasitized Anastrepha obliqua (Diptera, Tephritidae) larvae

Abstract

The hemocyte types, in addition to total and differential hemocyte counts were studied in parasitized and unparasitized Anastrepha obliqua larvae at the beginning and at the end of the third instar. In both developmental phases, in parasitized and unparasitized larvae, prohemocytes, plasmatocytes, granulocytes, adipohemocytes, spherulocytes and oenocytoids cells were observed. Mitotic figures indicate prohemocytes as stem cells. Prohemocytes, plasmatocytes and granulocytes are the most numerous cells in the hemolymph of A. obliqua. Difference in the total number of hemocytes was observed between unparasitized and parasitized larvae at the end of the third instar, but not at the beginning.

Changes in hemocytes of Plutella xylostella after parasitism by Diadegma semiclausum

“…These cells are considered to be the stem cells from which the main types differentiate (Peake and Crossley, 1979;Lea, 1986). Through the examination by TEM, necrosis of prohemocytes and damage of the hematopoietic organs in the P. xylostella larvae parasitized by D. semiclausum were observed, as seen in the earlier work including Orgyia leucostigma larvae parasitized by Cotesia melanoscela (Guzo and Stoltz, 1987), Anastrepha obliqua (Diptera, Tephritidae) larvae parasitized by braconids (Silva et al, 2002) and Pseudaletia separata larvae parasitized by Cotesia kariyai ( Teramoto and Tanaka, 2004). However, in contrast to the observations of nuclear pycnosis in an unidentified population of cells in the parasitized O. leucostigma larvae (Guzo and Stoltz, 1987) and nuclear apoptosis in the circulating hemocytes in the parasitized P. separata larvae (Teramoto and Tanaka, 2004), no segmented-DNA in the nuclei of mature hemocytes had been detected in our studies.…”

Hemocyte quantitative changes in Anticarsia gemmatalis (Lepidoptera: Noctuidae) larvae infected by AgMNPV

“…1992), D. saccharalis (Barduco et al 1988;Bombonato and Gregorio, 1995;Falleiros et al, 2003), Lacanobia oleracea (Richards and Edwards, 1999). Our results are similar to those observed by Silva et al (2002), who reported the absence of quantitative alterations of OE in response to pathogens in the hemocoel of A. obliqua larvae and are discordant to Bauer et al (1998), who reported the increase of this cellular type in larvae of P. brassicae parasited by Cotesia glomerata. However, this species is a parasitoid and we worked with a virus that might have led to the different results.…”

“…Different functions are attributed to the SP, as: tecidual remodeling, substance transport and synthesis , what could justify the absence of differences between non-infected and infected A. gemmatalis larvae. The PR showed a low rate of occurrence in A. gemmatalis, in agreement with Chiang et al (1988), Bombonato and Gregório (1995), Falleiros et al (2003), and in disagreement with Silva et al (2002), who reported the frequency of 38% for this cell type in Anastrepha obliqua. As the results obtained in infected larvae and non-infected larvae (Andrade et al, 2003) were similar, we can suggest that this cellular type is not directly involved in the immune responses to the AgMNPV.…”

Morphological characterization of hemocyte types in some species belonging to Tettigoniidae and Pamphagidae (Insecta: Orthoptera)

“…They were determined as rounded or ovoid in shape in P. demoleus (Jalali and Salehi, 2008). In the larvae of A. obliqua, the spherulocytes had various shapes and there were highly basophilic or acidophilic spherules or spherical vacuoles in cytoplasm (Silva et al, 2002). In this work, many spherical vacuoles were determined in the cytoplasm of these cells.…”