Optimization of in-house ELISA based on recombinant major sperm protein (rMSP) of Dictyocaulus viviparus for the detection of lungworm infection in cattle

The lungworm Dictyocaulus viviparus is one of the most economically important bovine parasites in temperate climate regions. Following infection, D. viviparus induces a temporary protective immunity, and a vaccine based on attenuated, infective larvae is commercially available. However, due to several disadvantages of the live vaccine, the development of a recombinant subunit vaccine is highly desirable. Therefore, the major sperm protein (MSP), which is essential for the parasite’s reproduction, was tested as a recombinantly Escherichia coli-expressed glutathione-S-transferase (GST)-fused vaccine antigen in immunization trials with two different adjuvants, Quil A and Al(OH)3. Calves (N = 4 per group) were immunized on study day (SD) 0, 21 and 42 and given a challenge infection on SD 63–65. The two control groups received only the respective adjuvant. Based on geometric means (GM), a 53.64% reduction in larvae per female worm was observed in the rMSP Quil A group vs. its control group (arithmetic means (AM): 54.43%), but this difference was not statistically significant. In the rMSP Al(OH)3 group, the mean number of larvae per female worm was even higher than in the respective control group (GM: 9.24%, AM: 14.14%). Furthermore, male and female worm burdens and the absolute number of larvae did not differ significantly, while the Al(OH)3 control group harbored significantly longer worms than the vaccinated group. Vaccinated animals showed a rise in rMSP-specific antibodies, particularly IgG and its subclass IgG1, and the native protein was detected by immunoblots. Although rMSP alone did not lead to significantly reduced worm fecundity, it might still prove useful as part of a multi-component vaccine.

Download Full-text

The diagnostic antigen encoded by gene fragment Dv3-14: A major sperm protein of Dictyocaulus viviparus

International Journal for Parasitology ◽

10.1016/0020-7519(93)90014-p ◽

1993 ◽

Vol 23 (3) ◽

pp. 383-389 ◽

Cited By ~ 15

Author(s):

T. Schnieder

Keyword(s):

Major Sperm Protein ◽

Gene Fragment ◽

Sperm Protein ◽

Dictyocaulus Viviparus ◽

Diagnostic Antigen

Download Full-text

Localized Depolymerization of the Major Sperm Protein Cytoskeleton Correlates with the Forward Movement of the Cell Body in the Amoeboid Movement of Nematode Sperm

The Journal of Cell Biology ◽

10.1083/jcb.146.5.1087 ◽

1999 ◽

Vol 146 (5) ◽

pp. 1087-1096 ◽

Cited By ~ 40

Author(s):

Joseph E. Italiano ◽

Murray Stewart ◽

Thomas M. Roberts

Keyword(s):

Cell Body ◽

Body Movement ◽

Leading Edge ◽

Amoeboid Movement ◽

Major Sperm Protein ◽

Membrane Protrusion ◽

Forward Movement ◽

Sperm Protein ◽

Amoeboid Motility ◽

Tightly Coupled

The major sperm protein (MSP)-based amoeboid motility of Ascaris suum sperm requires coordinated lamellipodial protrusion and cell body retraction. In these cells, protrusion and retraction are tightly coupled to the assembly and disassembly of the cytoskeleton at opposite ends of the lamellipodium. Although polymerization along the leading edge appears to drive protrusion, the behavior of sperm tethered to the substrate showed that an additional force is required to pull the cell body forward. To examine the mechanism of cell body movement, we used pH to uncouple cytoskeletal polymerization and depolymerization. In sperm treated with pH 6.75 buffer, protrusion of the leading edge slowed dramatically while both cytoskeletal disassembly at the base of the lamellipodium and cell body retraction continued. At pH 6.35, the cytoskeleton pulled away from the leading edge and receded through the lamellipodium as its disassembly at the cell body continued. The cytoskeleton disassembled rapidly and completely in cells treated at pH 5.5, but reformed when the cells were washed with physiological buffer. Cytoskeletal reassembly occurred at the lamellipodial margin and caused membrane protrusion, but the cell body did not move until the cytoskeleton was rebuilt and depolymerization resumed. These results indicate that cell body retraction is mediated by tension in the cytoskeleton, correlated with MSP depolymerization at the base of the lamellipodium.

Download Full-text

Supramolecular assemblies of the Ascaris suum major sperm protein (MSP) associated with amoeboid cell motility

Journal of Cell Science ◽

10.1242/jcs.107.10.2941 ◽

1994 ◽

Vol 107 (10) ◽

pp. 2941-2949

Author(s):

K.L. King ◽

M. Stewart ◽

T.M. Roberts

Keyword(s):

Ascaris Suum ◽

Leading Edge ◽

Intrinsic Property ◽

Basic Unit ◽

Major Sperm Protein ◽

Sperm Protein ◽

Amoeboid Cell ◽

Left Handed ◽

Self Association

Sperm of the nematode, Ascaris suum, are amoeboid cells that do not require actin or myosin to crawl over solid substrata. In these cells, the role usually played by actin has been taken over by major sperm protein (MSP), which assembles into filaments that pack the sperm pseudopod. These MSP filaments are organized into multi-filament arrays called fiber complexes that flow centripetally from the leading edge of the pseudopod to the cell body in a pattern that is intimately associated with motility. We have characterized structurally a hierarchy of helical assemblies formed by MSP. The basic unit of the MSP cytoskeleton is a filament formed by two subfilaments coiled around one another along right-handed helical tracks. In vitro, higher-order assemblies (macrofibers) are formed by MSP filaments that coil around one another in a left-handed helical sense. The multi-filament assemblies formed by MSP in vitro are strikingly similar to the fiber complexes that characterize the sperm cytoskeleton. Thus, self-association is an intrinsic property of MSP filaments that distinguishes these fibers from actin filaments. The results obtained with MSP help clarify the roles of different aspects of the actin cytoskeleton in the generation of locomotion and, in particular, emphasize the contributions made by vectorial assembly and filament bundling.

Download Full-text