Name: a colorimetric assay that specifically measures granzyme b proteolytic activity: hydrolysis of boc-ala-ala-asp-s-bzl
Uploaded: 2014-11-28T15:00:00
Description: Watch this Scientific Journal Video about A Colorimetric Assay that Specifically Measures Granzyme B Proteolytic Activity: Hydrolysis of Boc-Ala-Ala-Asp-S-Bzl at JoVE.com

This work received support through grant HA 6136/1-1 from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) to MH. JAT is supported by Program and Project Grants from the National Health and Medical Research Council of Australia.

NOTE: Spleens were derived from mice (6-10 weeks of age) and all animal experiments were performed according to the animal ethics guidelines of the Peter MacCallum Cancer Centre (E486).
1. Preparation of Samples.
<ol>
	<li>Preparation of activated mouse NK cells.
	<ol>
		<li>Isolate primary naive NK cells from single-cell suspensions of the spleens of C57BL/6 or B6.GrzmB-/- (GzmB gene null) mice by negative selection using commercially available kits.</li>
		<li>Follow the manufactu...

<ol>
	<li>Trapani, J. A., Browne, K. A., Dawson, M., Smyth, 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=Immunopurification+of+functional+Asp-ase+(natural+killer+cell+granzyme+B)+using+a+monoclonal+antibody).">Immunopurification of functional Asp-ase (natural killer cell granzyme B) using a monoclonal antibody).</a> Biochem Biophys Res Commun. 195 (2), 910-920 (1993).</li><li>Ewen, C. L., Kane, K. P., Bleackley, R. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+quarter+century+of+granzymes.">A quarter century of granzymes.</a> Cell Death Differ. 19 (1), 28-35 (2012).</li><li>Hoves, S., Trapani, J. 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J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cytotoxic+T+lymphocyte+granules+are+secretory+lysosomes,+containing+both+perforin+and+granzymes.">Cytotoxic T lymphocyte granules are secretory lysosomes, containing both perforin and granzymes.</a> J Exp Med. 173 (5), 1099-1109 (1991).</li><li>Berthou, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acquisition+of+granzyme+B+and+Fas+ligand+proteins+by+human+keratinocytes+contributes+to+epidermal+cell+defense.">Acquisition of granzyme B and Fas ligand proteins by human keratinocytes contributes to epidermal cell defense.</a> J Immunol. 159 (11), 5293-5300 (1997).</li><li>Tschopp, C. 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A., Brasacchio, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Controversies+in+granzyme+biology.">Controversies in granzyme biology.</a> Tissue Antigens. 80 (6), 477-487 (2012).</li><li>Walch, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cytotoxic+cells+kill+intracellular+bacteria+through+granulysin-mediated+delivery+of+granzymes.">Cytotoxic cells kill intracellular bacteria through granulysin-mediated delivery of granzymes.</a> Cell. 157 (6), 1309-1323 (2014).</li><li>Odake, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+and+murine+cytotoxic+T+lymphocyte+serine+proteases:+subsite+mapping+with+peptide+thioester+substrates+and+inhibition+of+enzyme+activity+and+cytolysis+by+isocoumarins.">Human and murine cytotoxic T lymphocyte serine proteases: subsite mapping with peptide thioester substrates and inhibition of enzyme activity and cytolysis by isocoumarins.</a> Biochemistry. 30 (8), 2217-2227 (1991).</li><li>Casciola-Rosen, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+and+human+granzyme+B+have+distinct+tetrapeptide+specificities+and+abilities+to+recruit+the+bid+pathway.">Mouse and human granzyme B have distinct tetrapeptide specificities and abilities to recruit the bid pathway.</a> J Biol Chem. 282 (7), 4545-4552 (2007).</li><li>Kaiserman, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+major+human+and+mouse+granzymes+are+structurally+and+functionally+divergent.">The major human and mouse granzymes are structurally and functionally divergent.</a> J Cell Biol. 175 (4), 619-630 (2006).</li><li>Powers, J. C., Kam, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peptide+thioester+substrates+for+serine+peptidases+and+metalloendopeptidases.">Peptide thioester substrates for serine peptidases and metalloendopeptidases.</a> Methods Enzymol. 248, 3-18 (1995).</li><li>Hagn, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Activated+mouse+B+cells+lack+expression+of+granzyme.">Activated mouse B cells lack expression of granzyme.</a> B. J Immunol. 188 (2), 3886-3892 (2012).</li><li>Konjar, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+and+mouse+perforin+are+processed+in+part+through+cleavage+by+the+lysosomal+cysteine+proteinase+cathepsin+L.">Human and mouse perforin are processed in part through cleavage by the lysosomal cysteine proteinase cathepsin L.</a> Immunology. 131 (2), 257-267 (2010).</li><li>Sutton, V. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Residual+active+granzyme+B+in+cathepsin+C-null+lymphocytes+is+sufficient+for+perforin-dependent+target+cell+apoptosis.">Residual active granzyme B in cathepsin C-null lymphocytes is sufficient for perforin-dependent target cell apoptosis.</a> J Cell Biol. 176 (4), 425-433 (2007).</li><li>Trapani, J. A., Smyth, M. J., Apostolidis, V. A., Dawson, M., Browne, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Granule+serine+proteases+are+normal+nuclear+constituents+of+natural+killer+cells.">Granule serine proteases are normal nuclear constituents of natural killer cells.</a> J Biol Chem. 269 (28), 18359-18365 (1994).</li><li>Cullen, S. P., Adrain, C., Luthi, A. U., Duriez, P. J., Martin, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+and+murine+granzyme+B+exhibit+divergent+substrate+preferences.">Human and murine granzyme B exhibit divergent substrate preferences.</a> J Cell Biol. 176 (4), 435-444 (2007).</li><li>Thornberry, N. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+combinatorial+approach+defines+specificities+of+members+of+the+caspase+family+and+granzyme+B.+Functional+relationships+established+for+key+mediators+of+apoptosis.">A combinatorial approach defines specificities of members of the caspase family and granzyme B. Functional relationships established for key mediators of apoptosis.</a> J Biol Chem. 272 (29), 17907-17911 (1997).</li><li>Bird, C. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+regulation+of+apoptosis:+the+cytotoxic+lymphocyte+serpin+proteinase+inhibitor+9+protects+against+granzyme+B-mediated+apoptosis+without+perturbing+the+Fas+cell+death+pathway.">Selective regulation of apoptosis: the cytotoxic lymphocyte serpin proteinase inhibitor 9 protects against granzyme B-mediated apoptosis without perturbing the Fas cell death pathway.</a> Mol Cell Biol. 18 (11), 6387-6398 (1998).</li><li>Bots, M., Medema, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Serpins+in+T+cell+immunity.">Serpins in T cell immunity.</a> J Leukoc Biol. 84 (5), 1238-1247 (2008).</li><li>Sun, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+family+of+10+murine+ovalbumin+serpins+includes+two+homologs+of+proteinase+inhibitor+8+and+two+homologs+of+the+granzyme+B+inhibitor+(proteinase+inhibitor+9).">A new family of 10 murine ovalbumin serpins includes two homologs of proteinase inhibitor 8 and two homologs of the granzyme B inhibitor (proteinase inhibitor 9).</a> J Biol Chem. 272 (24), 15434-15441 (1997).</li><li>Bird, C. H., Hitchen, C., Prescott, M., Harper, I., Bird, P. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immunodetection+of+granzyme+B+tissue+distribution+and+cellular+localisation.">Immunodetection of granzyme B tissue distribution and cellular localisation.</a> Methods Mol Biol. 844, 237-250 (2012).</li><li>Jenkins, M. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visualizing+CTL+activity+for+different+CD8++effector+T+cells+supports+the+idea+that+lower+TCR/epitope+avidity+may+be+advantageous+for+target+cell+killing.">Visualizing CTL activity for different CD8+ effector T cells supports the idea that lower TCR/epitope avidity may be advantageous for target cell killing.</a> Cell Death Differ. 16 (4), 537-542 (2009).</li><li>Edwards, K. M., Kam, C. M., Powers, J. C., Trapani, J. 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Historically the granzymes were identified as key effector molecules of cytotoxic lymphocytes (CTL and NK cells) capable of inducing a rapid apoptotic death in target cells. This was principally due to the action of GzmB, which cleaved target substrate molecules at aspartate (D) residues and thus was able to activate the caspase cascade by both cleaving pro-caspases, as well as several of their downstream targets. However, it is now appreciated that GzmB expression is not confined to lymphoid cytotoxic cells and its func...

Granzymes are a family of serine proteases found in the secretory lysosomes of natural killer (NK) cells and cytotoxic T lymphocytes (CTL) 1. Five different granzymes exist in humans (A, B, H, K and M), and ten in mice (A - G, K, M and N) 2,3. Granzyme A and Granzyme B (GzmA, GzmB) are the most abundant and have been extensively investigated in the human and rodent setting.
The classic function of GzmB is the induction of apoptosis in target cells executed in conjunction with the pore-forming protein perforin, which permits the granzyme to access the target cell cytosol 4. Although GzmB expression is unequivocally found in cytotoxic lymphocytes, recent studies have been addressing a variety of other GzmB-expressing cell types, including but not limited to keratinocytes 5, basophils 6, mast cells 7, plasmacytoid dendritic cells 8, and B cells 9,10. In this context, non-apoptotic GzmB functions were revealed ranging from participation in inflammatory processes, tissue remodelling and other immunoregulatory properties 11-14.
Given that a broader biological role has been proposed for GzmB than previously suspected, researchers require reliable and specific tools for its detection. Of advantage is GzmB&#8217;s specific requirement to cleave on the carboxyl side of aspartic acid residues, a property unique among eukaryotic serine proteases 15. Mouse, human and rat GzmB are structurally very similar, however the extended substrate specificity of mouse GzmB differs subtly from that of both human and rat 16, which means that certain generic substrates with Asp at the terminal (P1) can be cleaved efficiently by GzmB from all three species, whereas other substrates with more complicated sequences upstream of P1 may give widely variable results. In both the past and more recent literature, this fact has caused considerable confusion and misinterpretation of the biological significance of some experimental findings, even though carefully controlled, kinetic studies have sought to correct the situation 17.
In this paper we have sought to illustrate these points using two commercially available substrates, namely Boc-Ala-Ala-Asp-SBzl and N-acetyl-Ile-Glu-Pro-Asp-p-nitroanilide. The two reagents do generate different reactive groups following cleavage (a free sulphydryl versus a fluorescent free paranitroanilide), but this has no effect whatever on proteolytic cleavage. The described protocol is a modern adaption of a very old protocol 18, but should help investigators to use the different GzmB substrates appropriately, while also providing a methodological framework for detecting the activity of other granzymes, such as GzmA and GzmH.

<table border="0" cellpadding="0" cellspacing="0" width="1133">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:284px;">Product</td>
			<td style="width:241px;">Company</td>
			<td style="width:181px;">Catalogue number</td>
			<td style="width:427px;">Comment/description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Boc-Ala-Ala-Asp-S-Bzl</td>
			<td>SM Biochemicals LLC, CA</td>
			<td>SMSB05</td>
			<td>Granzyme B substrate (mouse and human)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ac-IEPD-pNA&#160;</td>
			<td>SM Biochemicals LLC, CA</td>
			<td>SMPNA009</td>
			<td>Granzyme B substrate (only human)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">N-a-CBZ-L-lysine-S-Bzl</td>
			<td>Sigma-Aldrich</td>
			<td>C3647</td>
			<td>Granzyme A substrate</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Suc-Phe-Leu-Phe-S-Bzl</td>
			<td>SM Biochemicals LLC, CA</td>
			<td>SB025</td>
			<td>Granzyme H substrate</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">5,5&#8217;-dithio-bis(2-nitrobenzoic acid)&#160;</td>
			<td>Sigma-Aldrich</td>
			<td>D8130</td>
			<td>&#160;DTNB, Ellman&#8217;s Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">NK cell isolation kit II mouse</td>
			<td>Miltenyi Biotec GmbH</td>
			<td style="width:181px;">130-096-892</td>
			<td style="width:427px;">negative selection kit</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">NK cell isolation kit human</td>
			<td>Miltenyi Biotec GmbH</td>
			<td>130-092-657</td>
			<td style="width:427px;">negative selection kit</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;"></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Plate reader</td>
			<td>Biorad iMark</td>
			<td></td>
			<td>Biorad Microplate Manager Software Version MPM6.3</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Serocluster U-bottom vinyl 96-well plate</td>
			<td>Corning, MA, USA</td>
			<td>2797</td>
			<td></td>
		</tr>
	</tbody>
</table>

a colorimetric assay that specifically measures granzyme b proteolytic activity: hydrolysis of boc-ala-ala-asp-s-bzl

The serine protease Granzyme B (GzmB) mediates target cell apoptosis when released by cytotoxic T lymphocytes (CTL) or natural killer (NK) cells. GzmB is the most studied granzyme in humans and mice and therefore, researchers need specific and reliable tools to study its function and role in pathophysiology. This especially necessitates assays that do not recognize proteases such as caspases or other granzymes that are structurally or functionally related. Here, we apply GzmB&#8217;s preference for cleavage after aspartic acid residues in a colorimetric assay using the peptide thioester Boc-Ala-Ala-Asp-S-Bzl. GzmB is the only mammalian serine protease capable of cleaving this substrate. The substrate is cleaved with similar efficiency by human, mouse and rat GzmB, a property not shared by other commercially available peptide substrates, even some that are advertised as being suitable for this purpose. This protocol is demonstrated using unfractionated lysates from activated NK cells or CTL and is also suitable for recombinant proteases generated in a variety of prokaryotic and eukaryotic systems, provided the correct controls are used. This assay is a highly specific method to ascertain the potential pro-apoptotic activity of cytotoxic molecules in mammalian lymphocytes, and of their recombinant counterparts expressed by a variety of methodologies.

The Boc-AAD-S-Bzl substrate is specific for GzmB
The serine protease GzmB is a major constituent of cytotoxic lymphocytes (CTL and NK cells) and is predominantly responsible for inducing rapid apoptotic death in target cells, such as virus-infected or transformed cells. This is largely due to its substrate preference for cleavage after certain specific aspartate residues in selected proteins, an attribute shared with the caspases, which also cleave after aspartate residues but...

Watch this Scientific Journal Video about A Colorimetric Assay that Specifically Measures Granzyme B Proteolytic Activity: Hydrolysis of Boc-Ala-Ala-Asp-S-Bzl at JoVE.com

A Colorimetric Assay that Specifically Measures Granzyme B Proteolytic Activity: Hydrolysis of Boc-Ala-Ala-Asp-S-Bzl

We describe a simple, quantitative colorimetric assay that specifically measures the proteolytic activity of human, mouse or rat Granzyme B (GzmB). This protocol can be easily adapted for determining protease activity of other granule serine proteases by the hydrolysis of other synthetic peptide substrates with an appropriate recognition sequence.

The serine protease Granzyme B (GzmB) mediates target cell apoptosis when released by cytotoxic T lymphocytes (CTL) or natural killer (NK) cells. GzmB is ...

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