TMS was supported by the Harlan Trust Fellowship (GWU) during this study. Funding for field collection and breeding L. fasciola and E. delphinii was provided by NSF grant DEB 0642438 to JTL.

1. Material Preparation
<ol>
	<li>Prepare needles (1-2 &mu;m tip and 3-4 mm taper) using borosilicate glass capillary tubes and a micropipette puller. Instrument settings: ramp: 561; velocity: 20; heat: 560; delay: 1; pull: 100; pressure: 500.</li>
	<li>Prepare the collection solution: 60% of Grace's Medium (GM) supplemented with 10% of Fetal Bovine Serum (FBS) and 20% of Anticoagulant Buffer (98 mM NaOH, 186 mM NaCI, 1.7 mM EDTA and 41 mM citric acid, pH 4.5). The above solution is prepared fresh under sterile conditi...

<ol>
	<li>Hartenstein, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blood+cells+and+blood+cell+development+in+the+animal+kingdom.">Blood cells and blood cell development in the animal kingdom.</a> Annu. Rev. Cell Dev. Biol. 22, 677 (2006).</li><li>Wood, W., Jacinto, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+melanogaster+embryonic+haemocytes:+masters+of+multitasking.">Drosophila melanogaster embryonic haemocytes: masters of multitasking.</a> Nat. Rev. Mol. Cell Biol. 8 (7), 542 (2007).</li><li>Strand, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+insect+cellular+immune+response.">The insect cellular immune response.</a> Insect Sci. 15 (1), 1 (2008).</li><li>Fauvarque, M. O., Williams, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+cellular+immunity:+a+story+of+migration+and+adhesion.">Drosophila cellular immunity: a story of migration and adhesion.</a> J. Cell Sci. 124 (9), 1373 (2011).</li><li>Nehme, N. T., Quintin, J., Cho, J. H., Lee, J., Lafarge, M. C., Kocks, C., Ferrandon, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Relative+roles+of+the+cellular+and+humoral+responses+in+the+Drosophila+host+defense+against+three+gram-positive+bacterial+infections.">Relative roles of the cellular and humoral responses in the Drosophila host defense against three gram-positive bacterial infections.</a> PLoS One. 6 (3), e14743 (2011).</li><li>Ulvila, J., Vanha-Aho, L. M., R&#228;met, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+phagocytosis+-+still+many+unknowns+under+the+surface.">Drosophila phagocytosis - still many unknowns under the surface.</a> APMIS. 119 (10), 651 (2011).</li><li>Moreira, C. G., Regan, J. C., Zaidman-Remy, A., Jacinto, A., Praq, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+hemocyte+migration:+an+in+vivo+assay+for+directional+cell+migration.">Drosophila hemocyte migration: an in vivo assay for directional cell migration.</a> Methods Mol. Biol. 769, 249 (2011).</li><li>Hillyer, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mosquito+immunity.">Mosquito immunity.</a> Adv. Exp. Med. Biol. 708, 218 (2010).</li><li>Castillo, J. C., Robertson, A. E., Strand, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+hemocytes+from+the+mosquitoes+Anopheles+gambiae+and+Aedes+aegypti.">Characterization of hemocytes from the mosquitoes Anopheles gambiae and Aedes aegypti.</a> Insect Biochem. Mol. Biol. 36 (12), 891 (2006).</li><li>Jiang, H., Vilcinskas, A., Kanost, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immunity+in+lepidopteran+insects.">Immunity in lepidopteran insects.</a> Adv. Exp. Med. Biol. 708, 181 (2010).</li><li>Eleftherianos, I., Xu, M., Yadi, H., ffrench-Constant, R. H., Reynolds, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plasmatocyte-spreading+peptide+(PSP)+plays+a+central+role+in+insect+cellular+immune+defenses+against+bacterial+infection.">Plasmatocyte-spreading peptide (PSP) plays a central role in insect cellular immune defenses against bacterial infection.</a> J. Exp. Biol. 212 (12), 1840 (2009).</li><li>Ribeiro, C., Breh&#233;lin, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insect+haemocytes:+what+type+of+cell+is+that.">Insect haemocytes: what type of cell is that.</a> J. Insect Physiol. 52 (5), 417 (2006).</li><li>Beetz, S., Brinkmann, M., Trenczek, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differences+between+larval+and+pupal+hemocytes+of+the+tobacco+hornworm,+Manduca+sexta,+determined+by+monoclonal+antibodies+and+density+centrifugation.">Differences between larval and pupal hemocytes of the tobacco hornworm, Manduca sexta, determined by monoclonal antibodies and density centrifugation.</a> J. Insect Physiol. 50 (9), 805 (2004).</li><li>Beetz, S., Holthusen, T. K., Koolman, J., Trenczek, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Correlation+of+hemocyte+counts+with+different+developmental+parameters+during+the+last+larval+instar+of+the+tobacco+hornworm,+Manduca+sexta.">Correlation of hemocyte counts with different developmental parameters during the last larval instar of the tobacco hornworm, Manduca sexta.</a> Arch. Insect Biochem. Physiol. 67 (2), 63 (2008).</li><li>Eleftherianos, I., Joyce, S., ffrench-Constant, R. H., Clarke, D. J., Reynolds, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probing+the+tri-trophic+interaction+between+insects,+nematodes+and+Photorhabdus.">Probing the tri-trophic interaction between insects, nematodes and Photorhabdus.</a> Parasitology. 137 (11), 1695 (2010).</li><li>Qayum, A. 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No conflicts of interest declared.

Methods for extracting hemocytes from medically important insects and lepidopteran model insects have previously been reported 9, 14. Hemocyte extraction methods are adapted according to the insect species, the developmental stage of the insect and its morphological features. For example, hemolymph isolation from Manduca larvae can be readily performed by snipping the curved horn near the end of the abdomen 15. Because slug caterpillars (Limacodidae) lack this abdominal structure, we have d...

<table border="1">
<tbody>
 <tr>
 <td>Name of the reagent</td>
 <td>Company</td>
 <td>Catalogue number</td>
 <td>Comments</td>
 </tr>
 <tr>
 <td>Micropipette puller</td>
 <td>Sutter Instruments</td>
 <td>P-1000 </td>
 <td></td>
 </tr>
 <tr>
 <td>Borosilicate glass tubes</td>
 <td>Sutter Instruments</td>
 <td>B100-50-10 </td>
 <td>OD: 1.0, ID: 0.50 mm</td>
 </tr>
 <tr>
 <td>Grace's Medium</td>
 <td>Sigma</td>
 <td>G8142</td>
 <td></td>
 </tr>
 <tr>
 <td>Fetal Bovine Serum </td>
 <td>Thermo Fisher Scientific</td>
 <td>SH3007102</td>
 <td>Heat inactivated</td>
 </tr>
 <tr>
 <td>Dumont #5 Forceps</td>
 <td>Fine science tools</td>
 <td>11252-40 </td>
 <td></td>
 </tr>
 <tr>
 <td>Neubauer hemocytometer</td>
 <td>Hausser Scientific</td>
 <td>3200 </td>
 <td></td>
 </tr>
 <tr>
 <td>Plastic tubing</td>
 <td>Tri-Tech</td>
 <td>TT-3-32OD </td>
 <td>OD: 3/32'', ID: 1/32'</td>
 </tr>
 <tr>
 <td>Glass medical syringe</td>
 <td>Fortuna Optima</td>
 <td>D-97877 </td>
 <td>50 ml volume</td>
 </tr>
 <tr>
 <td>Blunt end needle</td>
 <td>Small Parts</td>
 <td>NE-162PL-25 </td>
 <td>16 Gauge x 1" length </td>
 </tr>
 </tbody>
</table>

a simple protocol for extracting hemocytes from wild caterpillars

Insect hemocytes (equivalent to mammalian white blood cells) play an important role in several physiological processes throughout an insect's life cycle 1. In larval stages of insects belonging to the orders of Lepidoptera (moths and butterflies) and Diptera (true flies), hemocytes are formed from the lymph gland (a specialized hematopoietic organ) or embryonic cells and can be carried through to the adult stage. Embryonic hemocytes are involved in cell migration during development and chemotaxis regulation during inflammation. They also take part in cell apoptosis and are essential for embryogenesis 2. Hemocytes mediate the cellular arm of the insect innate immune response that includes several functions, such as cell spreading, cell aggregation, formation of nodules, phagocytosis and encapsulation of foreign invaders 3. They are also responsible for orchestrating specific insect humoral defenses during infection, such as the production of antimicrobial peptides and other effector molecules 4, 5. Hemocyte morphology and function have mainly been studied in genetic or physiological insect models, including the fruit fly, Drosophila melanogaster 6, 7, the mosquitoes Aedes aegypti and Anopheles gambiae 8, 9 and the tobacco hornworm, Manduca sexta 10, 11. However, little information currently exists about the diversity, classification, morphology and function of hemocytes in non-model insect species, especially those collected from the wild 12.
Here we describe a simple and efficient protocol for extracting hemocytes from wild caterpillars. We use penultimate instar Lithacodes fasciola (yellow-shouldered slug moth) (Figure 1) and Euclea delphinii (spiny oak slug) caterpillars (Lepidoptera: Limacodidae) and show that sufficient volumes of hemolymph (insect blood) can be isolated and hemocyte numbers counted from individual larvae. This method can be used to efficiently study hemocyte types in these species as well as in other related lepidopteran caterpillars harvested from the field, or it can be readily combined with immunological assays designed to investigate hemocyte function following infection with microbial or parasitic organisms 13.

The protocol described herein allows the collection of a minimum volume of 10-20 &mu;l of insect hemolymph from individual caterpillars. Hemocytes collected using this method are free of cell clumping, melanization defects, tissue debris or other contaminants. Therefore hemocytes can be readily observed and counted under the microscope, and several insects can be observed within a few hosur. We observed that the majority of hemocytes in our samples consisted of plasmatocytes 3 (hemocytes spreading asymmetrical...

Watch this Scientific Journal Video about A Simple Protocol for Extracting Hemocytes from Wild Caterpillars at JoVE.com

A Simple Protocol for Extracting Hemocytes from Wild Caterpillars

Insect hemocytes carry out many important functions, both immune and non-immune, throughout all stages of insect development. Our present knowledge of hemocyte types and function comes from studies on insect genetic models. Here, we present a method for extracting, quantifying and visualizing hemocytes from wild caterpillars.

Insect hemocytes (equivalent to mammalian white blood cells) play an important role in several physiological processes throughout an insect's life cycle ...

a-simple-protocol-for-extracting-hemocytes-from-wild-caterpillars

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16.1K 조회수.  The George Washington University. 곤충 hemocytes는 곤충 개발의 모든 단계에 걸쳐 면역 및 비 면역 모두 여러 중요한 기능을, 실시합니다. hemocyte 유형 및 기능의 현재 우리의 지식은 곤충 유전자 모델에 대한 연구에서 비롯됩니다. 여기, 우리는 추출 정량화과 야생 유충에서 hemocytes을 시각화하는 방법을 제시한다.