The ratio between class II and class I collagenase determines the amount of neutral protease activity required for efficient islet release from the rat pancreas

Brandhorst, Heide; Alt, A.; Huettler, S.; Raemsch-Guenther, N.; Kurfuerst, M.; Bretzel, Reinhard G.; Brandhorst, Daniel

doi:10.1016/j.transproceed.2004.12.256

Cited by 12 publications

(15 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These important findings were partially confirmed in a study in rats stressing particularly the effect of the ratio between collagenase class I and II on the required amount of NP (20). As a consequence of these generally established propositions enzyme production has aimed on purifying enzyme blends to the highest possible extent.…”

Section: Discussionmentioning

confidence: 80%

The Importance of Tryptic-like Activity in Purified Enzyme Blends for Efficient Islet Isolation

Brandhorst¹,

Friberg²,

Andersson³

et al. 2009

Transplantation

View full text Add to dashboard Cite

show abstract

Section: Discussionmentioning

confidence: 80%

The Importance of Tryptic-like Activity in Purified Enzyme Blends for Efficient Islet Isolation

Brandhorst¹,

Friberg²,

Andersson³

et al. 2009

Transplantation

View full text Add to dashboard Cite

show abstract

“…In fact, Lakey describes two components of CI collagenase, of which only one was associated (in a small number of cases) with isolation success (3). It should be noted that Lakey et al had the possibility of using batch enzymes containing only one component of class I collagenase (3,22). We expect in the future to test batches with similar characteristics in our laboratory.…”

Section: Discussionmentioning

confidence: 89%

“…Although neither of these correlates with the number of isolated islets, peak B correlates directly with the purity of the preparation. It was already reported that enzymes used for pancreas digestion affected islet purification (21)(22). Mechanisms should include the duration of digestion (and therefore of warm ischemia cell exposure), cell death, incomplete tissue digestion that collectively could contribute to exocrine cell degranulation and damage resulting in variable purification of islet preparation.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Characterization of Collagenase Blend Enzymes for Human Islet Transplantation

Antonioli¹,

Fermo

Cainarca

et al. 2007

Transplantation

View full text Add to dashboard Cite

Background. Efficient islet isolation represents a necessary requirement for successful islet transplantation as a treatment for type 1 diabetes. The choice of collagenase for pancreas digestion is critical for the isolation outcome, and Liberase™ is the most widely used enzyme, although large intra-batched variability in activity and efficiency has been observed. Methods. The aim of this study was to characterize Liberase™ components and their relative role in pancreas digestion. Liberase batches were characterized by microelectrophoresis. Results. By means of microelectrophoresis, we identified three main proteins each with different prevalences between batches. Two proteins were found to correspond to class I (CI) and one to class II (CII) collagenase. In a series of 163 islet isolations, we observed that the CII correlated with islet yield (PϽ0.001) and digestion time (PϽ0.001); additionally, CI directly correlated with purity (Pϭ0.028). Finally, when CII and one of the CI isoforms were Ͼ50 percentile, 15 of 36 preparations were transplanted, with 27 of 127 transplanted in the other cases (Pϭ0.013). Conclusion. These results represent an important step toward the characterization of enzymes, with the final aim of identifying key components for a standardized product.

show abstract

“… 14 , 15 A significant factor that can alter the proportion of CI within a blend is the degradation of CI. On the basis of previous studies, demonstrating that large amounts of NP diminish differences in the efficiency between different ratios of CII-to-CI, 16 we speculated that this discrepancy may be explained by an excessive use of supplementary NP, clostripain (CP) or thermolysin.…”

mentioning

confidence: 98%

Comparison of Neutral Proteases and Collagenase Class I as Essential Enzymes for Human Islet Isolation

Brandhorst

Kurfürst²,

Johnson

et al. 2016

Transplantation Direct

View full text Add to dashboard Cite

BackgroundEfficient islet isolation requires synergistic interaction between collagenase class I (CI) and class II (CII). The CI degradation alters the ratio between CI and CII and is responsible for batch-to-batch variations. This study compares the role of neutral protease (NP) plus clostripain (CP) with CI as essential enzymes for human islet isolation.MethodsHuman islets were isolated using 4 different enzyme mixtures composed of CII plus either intact (CI-115) or degraded CI (CI-100). Blends were administered either with or without NP/CP. Purified islets were cultured for 3 to 4 days before islet quality assessment.ResultsWhereas using intact CI-115 without NP/CP did not significantly reduce islet yield (3429 ± 631 vs 3087 ± 970 islet equivalent/g, nonsignificant), administration of degraded CI-100 without NP/CP decreased islet yield from 3501 ± 580 to 1312 ± 244 islet equivalent/g (P < 0.01), doubled the amount of undigested tissue from 11.8 ± 1.6 to 24.4 ± 1.2% (P < 0.01) and triplicated the percentage of trapped islets from 7.7 ± 2.8 to 22.5 ± 3.6% (P < 0.05). Islet yield did not vary between supplemented CI-115 and CI-100, but was increased using CI-115 when NP/CP was omitted (P < 0.05). A trend toward higher viability and increased secretory insulin response was noted in both CI-100 and CI-115 when NP/CP was not added.ConclusionsThis study suggests that NP/CP can compensate reduced CI activity. Future attempts to optimize enzyme blends should consider the possibility to increase the proportion of collagenase CI to reduce the need for potentially harmful NPs.

show abstract

The ratio between class II and class I collagenase determines the amount of neutral protease activity required for efficient islet release from the rat pancreas

Cited by 12 publications

References 9 publications

The Importance of Tryptic-like Activity in Purified Enzyme Blends for Efficient Islet Isolation

The Importance of Tryptic-like Activity in Purified Enzyme Blends for Efficient Islet Isolation

Characterization of Collagenase Blend Enzymes for Human Islet Transplantation

Comparison of Neutral Proteases and Collagenase Class I as Essential Enzymes for Human Islet Isolation

Contact Info

Product

Resources

About