The video demonstrates a procedure for collecting hemolymph from small brown planthoppers (SBPHs). It involves immobilizing the insect, extracting hemolymph using a micropipette, and analyzing protein concentrations across different life stages using SDS-PAGE. The findings indicate similar protein levels in larval and adult SBPHs.

collection and analysis of hemolymph from small brown planthopper (sbph)

Collecting Hemolymph from Small Arthropods

Both animal and plant viruses can be transmitted by arthropods, and these viruses pose a severe threat to human health and cause tremendous economic losses in agriculture1,2,3. Importantly, the arthropod hemolymph, which serves as the circulatory system and a vital element of the immune system in arthropods, plays an important role in regulating arboviral transmission. Viruses acquired through the arthropod guts are transported to other tissues only after successfully escaping the adverse hemolymph environment4,5,6,7. The lifecycle of viruses in the arthropod hemolymph involves virus survival in the fluid plasma, entry into the hemocyte, and transport to other tissues, and various virus-vector interaction mechanisms occur in the hemolymph8,9,10,11,12. For example, the vertical transmission of RSV by the SBPH is dependent on a molecular interaction between the SBPH vitellogenin protein and the RSV (rice stripe virus) capsid protein13,14. Some viruses may escape the immune response of the hemolymph by binding specific vector factors15,16,17,18. Therefore, investigating vector-virus interactions in the hemolymph of arthropods is important for developing a better understanding of arbovirus transmission.
The hemolymph of some small insects, such as planthoppers, leafhoppers, and some mosquitoes, is difficult to collect due to their size. To address this issue, several methods have been developed to collect hemolymph, including inserting a syringe needle directly into the insect body to extract a microvolume of the hemolymph, collecting exudate from the wound site with fine-tipped tweezers, and direct centrifugation. These methods have enabled the measurement of relative gene expression levels and viral titers within the hemolymph19,20,21. However, an effective method for quantifying the hemolymph volume, which is necessary for hemocyte counting, protein quantification, and enzyme activity analysis, is currently not available for these small insects.
The SBPH (small brown planthopper) is a type of small insect vector with a body length of about 2-4 mm. The SBPH is capable of transmitting a variety of plant viruses, including RSV, maize rough dwarf virus, and rice black streaked dwarf virus22,23,24. The interaction between the SBPH and RSV has been studied in depth over the past decade. To facilitate working with SBPHs, we developed a novel and simple method of collecting hemolymph. This method, which is based on the principle of capillary forces, uses a capillary with a scale mark to acquire the insect&#39;s hemolymph in a precise and quantifiable manner. This allows us to collect a specific volume of hemolymph from small insects efficiently and to study the hemolymph environment of small vectors in more detail.

Author Spotlight: A Precise and Quantifiable Method for Collecting Hemolymph from Small Arthropods  

A Precise and Quantifiable Method for Collecting Hemolymph from Small Arthropods

Our research focuses on arboviruses, insects, and plant interactions. Obtaining hemolymph samples from small arthropods presents a technical challenge for research on insect-borne diseases. This protocol shows a precise and quantifiable technique to counter this issue.Recent research developments in the transmission of arboviruses have discovered that viruses can manipulate several important vector-factors to break through the host barrier. This protocol is a simple, cost-effective and valuable technique that allows for precise quantification of the hemolymph. This method also offers valuable technology for starting the interactions between viruses and vectors.Our upcoming research will focus on understanding the molecular mechanisms of virus transmission by vector-insects while exploring and enhancing new operational techniques.

Watch this Scientific Journal Video about Collection and Analysis of Hemolymph from Small Brown Planthopper SBPH at JoVE.com

Collection and Analysis of Hemolymph from Small Brown Planthopper (SBPH)  

For this study, use small brown planthopper or SBPHs raised in rice seedlings. Once the cultures are ready, put the grown SBPHs into a centrifuge tube and place them in an ice bath for 10 to 30 minutes. Then place a frozen SBPH on a glass slide under a stereo microscope with its abdomen facing up and adjust the focus on its six legs.Prepare two high precision tweezers with ultra fine tips. Using one tweezer, press down on the insect's body to keep it in place and carefully pull off one leg with the other tweezer. Then gently press the insect's chest, allowing hemolymph to flow through the wound.To collect hemolymph, prepare a micropipette by placing one microliter capillary tube into the pipet bulb. Place the capillary tube close to the insect wound, holding the micropipette pipette bulb. Touch the capillary tip to the exuding hemolymph and collect it.Once the capillary tube reaches the desired scale line, slightly block the small hole on the pipette bulb with the finger to stop the absorbing process. Then discharge the collected hemolymph into 100 microliters of PBS buffer. The accuracy of hemolymph collection was confirmed via SDS-PAGE, which showed a similar protein content in all three hemolymph samples, collected separately.For larva, the total protein concentration was approximately 3.7 milligrams per milliliter. In adult female and male SBPHs, the protein concentrations were about 3.5 and 3.6 milligrams per milliliter respectively, showing no significant difference between the three samples. The larval hemolymph showed hemocytes of two to 20 nanometers in size.In addition, the cell concentration was comparable in the three collected hemolymph samples.

collection-and-analysis-of-hemolymph-from-small-brown-planthopper-sbph

Research

JoVE Journal

Biology

Arthropods are known to transmit a variety of viruses of medical and agricultural importance through their hemolymph, which is essential for virus transmission. Hemolymph collection is the basic technology for studying virus-vector interactions. Here, we describe a novel and simple method for the quantitative collection of hemolymph from small arthropods using Laodelphax striatellus (the small brown planthopper, SBPH) as a research model, as this arthropod is the main vector of rice stripe virus (RSV). In this protocol, the process begins by gently pinching off one leg of the frozen arthropod with fine-tipped tweezers and pressing the hemolymph out of the wound. Then, a simple micropipette consisting of a capillary and a pipette bulb is used to collect the transudative hemolymph from the wound according to the principle of capillary forces. Finally, the collected hemolymph can be dissolved into a specific buffer for further study. This new method for collecting hemolymph from small arthropods is a useful and efficient tool for further research on arboviruses and vector-virus interactions.

We describe a method to collect quantifiable hemolymph efficiently from small arthropods for subsequent analysis.