Isolation of human islets for autologous islet transplantation in children and adolescents with chronic pancreatitis

Abstract

Chronic pancreatitis is an inflammatory disease of the pancreas that causes permanent changes in the function and structure of the pancreas. It is most commonly a complication of cystic fibrosis or due to a genetic predisposition. Chronic pancreatitis generally presents symptomatically as recurrent abdominal pain, which becomes persistent over time. The pain eventually becomes disabling. Once specific medical treatments and endoscopic interventions are no longer efficacious, total pancreatectomy is the alternative of choice for helping the patient achieve pain control. While daily administrations of digestive enzymes cannot be avoided, insulin-dependent diabetes can be prevented by transplanting the isolated pancreatic islets back to the patient. The greater the number of islets infused, the greater the chance to prevent or at least control the effects of surgical diabetes. We present here a technical approach for the isolation and preservation of the islets proven to be efficient to obtain high numbers of islets, favoring the successful treatment of young patients.

Figure 1

Islet yield expressed as islet equivalent numbers.

Figure 2

Islet yield expressed as islet equivalent numbers per gram of pancreatic tissue actually digested.

Figure 3

In (a) Islet yield expressed as islet equivalent (IEQ) numbers per kg of patient body weight. In (b) Serum C-peptide levels 6 months after transplant. Case no. 9: Serum C-peptide levels 3 months post-transplant. NA: not available.

Figure 4

At the end of the isolation, some tissue is left in the digestion chamber. Of the undigested portion, only less than 20% was glandular, with a prevalence of fibrotic, calcified, and ductal tissue.

Figure 5

The pancreatic organ of young patients is subjected first to a stationary digestion characterized by prolonged infusion of prewarmed collagenase-neutral protease solution. Mechanical shaking is carried out after stationary digestion and limited in time to avoid excessive breakage of islets embedded in exocrine tissue.

Figure 6

Amount of tissue infused. After digestion and purification (when applied), the pancreatic cell pellet (comprised between 2.75 and 15 mL) is suspended in medium containing human serum albumin and bagged for infusion. Each bag contains a maximum of 5 mL of pellet tissue.

Figure 7

Number of cases in which the pancreas procurement fluid and/or the islet cells showed positive microbiology.