Immunological study in primary intestinal lymphangiectasia

Cryptococcal meningitis and cerebral vasculitis in a patient with primary intestinal lymphangiectasia: a case report

Primary intestinal lymphangiectasia (Waldmann's disease) is a rare exudative enteropathy without precisely assessed infectious risk. We report the case of a 49-year-old male patient with meningitis and cerebral vasculitis due to Cryptococcus neoformans complicating Waldmann's disease diagnosed 12 years ago. The treatment combined liposomal amphotericin B, 3 mg/kg daily plus flucytosine 25 mg/kg/6 h, both intravenously during 15 days, then fluconazole 800 mg daily during 8 weeks, and finally 200 mg daily indefinitely. Dexamethasone 0.4 mg/kg daily during the first week was gradually decreased over 2 months. The outcome was good, and the patient is still followed 3 years later without any recurrence.

Protein-losing Enteropathy as a Complication and/or Differential Diagnosis of Common Variable Immunodeficiency

As protein-losing enteropathy (PLE) can lead to hypogammaglobulinemia and lymphopenia, and since common variable immunodeficiency (CVID) is associated with digestive complications, we wondered if (1) PLE could occur during CVID and (2) specific features could help determine whether a patient with antibody deficiency has CVID, PLE, or both. Eligible patients were thus classified in 3 groups: CVID + PLE (n = 8), CVID-only (= 19), and PLE-only (n = 13). PLE was diagnosed using fecal clearance of α1-antitrypsin or 111In-labeled albumin. Immunoglobulin (Ig) A, G, and M, naive/memory B and T cell subsets were compared between each group. CVID + PLE patients had multiple causes of PLE: duodenal villous atrophy (5/8), nodular follicular hyperplasia (4/8), inflammatory bowel disease-like (4/8), portal hypertension (4/8), giardiasis (3/8), and pernicious anemia (1/8). Compared to the CVID-only group, CVID + PLE patients had similar serum Ig levels, B cell subset counts, but lower naive T cell proportion and IgG replacement efficiency index. Compared to the CVID-only group, PLE-only patients did not develop infections but had higher serum levels of IgG (p = 0.03), IgA (p < 0.0001), and switched memory B cells (p = 0.001); and decreased naive T cells (CD4⁺: p = 0.005; CD8⁺: p < 0.0001). Compared to the PLE-only group, CVID + PLE patients had higher infection rates (p = 0.0003), and lower serum Ig (especially IgA: p < 0.001) and switched memory B cells levels. In conclusion, PLE can occur during CVID and requires higher IgG replacement therapy dosage. PLE can also mimic CVID and is associated with milder immunological abnormalities, notably mildly decreased to normal serum IgA and switched memory B cell levels.

Primary intestinal lymphangiectasia presenting as limb convulsions: A case report

BACKGROUND

Primary intestinal lymphangiectasia (PIL) is a rare protein-losing enteropathy characterized by abnormally dilated lymphatic structures, resulting in leakage of lymph (rich in protein, lymphocytes, and fat) from the intestinal mucosal and submucosal layers and thus hypoproteinemia, lymphopenia, hypolipidemia, and pleural effusion.

CASE SUMMARY

A 19-year-old Chinese male patient complained of recurrent limb convulsions for the last 1 year. Laboratory investigations revealed low levels of calcium and magnesium along with hypoproteinemia and high parathyroid hormone levels, whereas gastroscopy exhibited chronic non-atrophic gastritis and duodenal lymphatic dilatation. Subsequent gastric biopsy showed moderate chronic inflammatory cell infiltration distributed around a small mucosal patch in the descending duodenum followed by lymphatic dilatation in the mucosal lamina propria, which was later diagnosed as PIL. The following appropriate medium-chain triglycerides nutritional support significantly improved the patient’s symptoms.

CONCLUSION

Since several diseases mimic the clinical symptoms displayed by PIL, like limb convulsions, low calcium and magnesium, and loss of plasma proteins, it is imperative to conduct a detailed analysis to avoid any misdiagnosis while pinpointing the correct clinical diagnosis and simultaneously ruling out other clinical aspects in the reported cases without any past disease history. A careful assessment should always be made to ensure an accurate diagnosis in a timely manner so that the patient can be delivered quality health services for a positive health outcome.

A primary intestinal lymphangiectasia hiding the diagnosis of pleural and pericardial tuberculosis: a clinical observation

Primary intestinal lymphangiectasia (Waldmann's disease) is an exudative enteropathy characterized by lymph leakage into the small bowel lumen leading to hypoalbuminemia, hypogammaglobulinemia and lymphopenia (particularly T-cell). The diagnosis is based on viewing the duodenal lymphangiectasia. A 20 years old female patient, treated for a primary intestinal lymphangiectasia, has consulted for anasarca. Etiological work-up reveals pleural and pericardial tuberculosis. The clinical aggravation of an enteropathy, particularly in adulthood, requires a search for a secondary etiology. Tuberculosis should be sought systematically.

Immune Abnormalities in Fontan Protein-Losing Enteropathy: A Case-Control Study

OBJECTIVE

To comprehensively characterize the immunologic characteristics of patients with protein-losing enteropathy (PLE) post-Fontan and compare them with patients without PLE post-Fontan.

STUDY DESIGN

Patients with PLE post-Fontan and age-matched controls post-Fontan were prospectively studied with laboratory markers of immune function. Infectious history was obtained by interview and chart review. The groups' demographics, cardiac history, immune characteristics, and infection history were compared using appropriate 2-group statistics.

RESULTS

A total of 16 patients enrolled (8 patients with PLE and 8 controls). All patients with PLE had lymphopenia compared with 25% of controls (P = .01). All patients with PLE had markedly depressed CD4 T cell counts (median 58 cells/μL) compared with controls (median 450 cells/μL, P = .0002); CD4% was also low in the PLE group (12.3%) and normal in control (36.9%, P = .004). Both groups had mildly depressed CD8 T cells and normal to slightly elevated natural killer and B-cell subsets. A majority of patients with PLE (62.5%) had negative titers to measles, mumps, and rubella vaccination, compared with no control Fontan with a negative titer (P = .03). Despite profoundly low CD4 counts, the frequency of infection was not different between groups with no reported opportunistic infections.

CONCLUSIONS

Patients with Fontan-associated PLE have extensive quantitative immune abnormalities, particularly CD4 deficiency. These immune abnormalities are similar to those found in non-Fontan patients with PLE caused by intestinal lymphangiectasia.

Classification of intestinal lymphangiectasia with protein-losing enteropathy: white villi type and non-white villi type

BACKGROUND/AIMS

We classified intestinal lymphangiectasia (IL) into two categories, the white and non-white villi types, and evaluated their clinical characteristics and therapeutic responses.

METHODS

Of the 988 patients who underwent double-balloon enteroscopy, 14 consecutive patients (7 men and 7 women, median age at onset 34 years) were enrolled with immunohistochemically confirmed IL with protein-losing enteropathy.

RESULTS

Enteroscopically the white villi type (n = 8) showed white plaques and white-tipped villi were scattered in the small bowel, while non-white villi type (n = 6) showed that apparently normal but under more detailed observation, low and round villi with a normal color were diffused. The serum albumin levels and fecal α1-antitrypsin clearance before treatment were significantly worse in the non-white villi type (p = 0.017 and 0.039, respectively), whereas the serum immunoglobulin A and M levels were significantly lower in the white villi type (p = 0.010 and 0.046, respectively). At gastroscopy, a non-cirrhotic snakeskin appearance was significantly observed in the non-white villi type (p = 0.015). The corticosteroid response was better in the non-white villi type (p = 0.015).

CONCLUSION

Two distinct subgroups were found in IL. This classification was useful in pathophysiological clustering and in predicting the therapeutic response.

Primary intestinal lymphangiectasia: Minireview

Primary idiopathic intestinal lymphangiectasia is an unusual disease featured by the presence of dilated lymphatic channels which are located in the mucosa, submucosa or subserosa leading to protein loosing enteropathy.Most often affected were children and generally diagnosed before third year of life but may be rarely seen in adults too. Bilateral pitting oedema of lower limb is the main clinical manifestation mimicking the systemic disease and posing a real diagnostic dilemma to the clinicians to differentiate it from other common systemic diseases like Congestive cardiac failure, Nephrotic Syndrome, Protein Energy Malnutrition, etc. Diagnosis can be made on capsule endoscopy which can localise the lesion but unable to take biopsy samples. Thus, recently double-balloon enteroscopy and biopsy in combination can be used as an effective diagnostic tool to hit the correct diagnosis. Patients respond dramatically to diet constituting low long chain triglycerides and high protein content with supplements of medium chain triglyceride. So early diagnosis is important to prevent untoward complications related to disease or treatment for the sake of accurate pathological diagnosis.

Role of immunoglobulin supplementation for secondary immunodeficiency associated with chylothorax after pediatric cardiothoracic surgery

OBJECTIVE

To evaluate whether intravenous immunoglobulin was linked to a reduction in sepsis in patients with prolonged chylothoraces postpediatric cardiothoracic surgery.

DESIGN

Retrospective observational cohort study.

SETTING

Tertiary pediatric cardiac surgical center.

PATIENTS

Children with chylothoraces postcardiothoracic surgery from 1998 to 2006 divided into two groups: with and without intravenous immunoglobulin supplementation.

INTERVENTION

Intravenous immunoglobulin supplementation.

MEASUREMENTS AND MAIN RESULTS

Thirty-seven with chylothoraces (median duration 14 days; interquartile range, 10-32 and median maximum chyle drainage 1.9 mL/kg/hr; interquartile range, 1-3) were included, and 16 (43%) received intravenous immunoglobulin. The degree of lymphopenia was worse with longer duration of chylothorax (p = .005). There was a trend toward immunoglobulin depletion-IgG (p = .07) and IgM (p = .07) with higher volume chyle loss. Twenty-two of 37 (59%) developed bloodstream infection and 24 of 37 (65%) developed sepsis related to other organ systems. The rate of bloodstream infection and of sepsis in other organ systems was high at 25 (95% confidence interval 17-39) and 23 (95% confidence interval 15-34) episodes per 1,000 intensive care unit days, respectively. Intravenous immunoglobulin was not related to the bloodstream infection rate: adjusted hazard ratio 0.88 (95% confidence interval 0.20-3.94; p = .87) or rate of sepsis in other organ systems: hazard ratio 2.31 (95% confidence interval 0.21-24.29; p = .49) or the proportion surviving to hospital discharge (p = .37).

CONCLUSION

Patients with prolonged, large-volume chyle loss had greater secondary immunodeficiency. Although the sample size was small and therefore able to detect only a large treatment effect from intravenous immunoglobulin, infectious outcomes were equal between the two groups.

Intestinal lymphangiectasia in adults

Intestinal lymphangiectasia in the adult may be characterized as a disorder with dilated intestinal lacteals causing loss of lymph into the lumen of the small intestine and resultant hypoproteinemia, hypogammaglobulinemia, hypoalbuminemia and reduced number of circulating lymphocytes or lymphopenia. Most often, intestinal lymphangiectasia has been recorded in children, often in neonates, usually with other congenital abnormalities but initial definition in adults including the elderly has become increasingly more common. Shared clinical features with the pediatric population such as bilateral lower limb edema, sometimes with lymphedema, pleural effusion and chylous ascites may occur but these reflect the severe end of the clinical spectrum. In some, diarrhea occurs with steatorrhea along with increased fecal loss of protein, reflected in increased fecal alpha-1-antitrypsin levels, while others may present with iron deficiency anemia, sometimes associated with occult small intestinal bleeding. Most lymphangiectasia in adults detected in recent years, however, appears to have few or no clinical features of malabsorption. Diagnosis remains dependent on endoscopic changes confirmed by small bowel biopsy showing histological evidence of intestinal lymphangiectasia. In some, video capsule endoscopy and enteroscopy have revealed more extensive changes along the length of the small intestine. A critical diagnostic element in adults with lymphangiectasia is the exclusion of entities (e.g. malignancies including lymphoma) that might lead to obstruction of the lymphatic system and “secondary” changes in the small bowel biopsy. In addition, occult infectious (e.g. Whipple’s disease from Tropheryma whipplei) or inflammatory disorders (e.g. Crohn’s disease) may also present with profound changes in intestinal permeability and protein-losing enteropathy that also require exclusion. Conversely, rare B-cell type lymphomas have also been described even decades following initial diagnosis of intestinal lymphangiectasia. Treatment has been historically defined to include a low fat diet with medium-chain triglyceride supplementation that leads to portal venous rather than lacteal uptake. A number of other pharmacological measures have been reported or proposed but these are largely anecdotal. Finally, rare reports of localized surgical resection of involved areas of small intestine have been described but follow-up in these cases is often limited.

Digital clubbing in primary intestinal lymphangiectasia: a case report

Primary intestinal lymphangiectasia (PIL), also known as Waldmann's disease, is a rare disorder characterized by dilated intestinal lacteals resulting in lymph leakage into the small bowel lumen and responsible for protein-losing enteropathy leading to lymphopenia, hypoalbuminemia and hypogammaglobulinemia. The symptoms usually start in early infancy. We report a case of secondary hyperparathyroidism, osteopenia, monoclonal gammopathy and digital clubbing in a 57-year-old patient with a 12-year history of discontinuous diarrhea. Malabsorption with inability to gain weight, and finally weight loss and formation of leg edema were associated with protein-losing enteropathy. A low-fat diet associated with medium-chain triglyceride supplementation was clinically effective as medical management in reducing diarrhea and leg edema, and promoting weight gain. Double-balloon enteroscopy and small bowel biopsy histopathology confirmed dilated intestinal lacteals. Digital clubbing associated with primary intestinal lymphangiectasia which may causally be related to chronic platelet excess has not been reported before.

Increased surface receptor Fas (CD95) levels on CD4+ lymphocytes in patients with primary intestinal lymphangiectasia

OBJECTIVE

Exudative enteropathy secondary to primary intestinal lymphangiectasia (PIL) is characterized by lymphopenia, hypogammaglobulinemia and hypoalbuminemia resulting from leakage of lymph fluid into the intestinal tract. The objective of this study was to better characterize the lymphopenia of PIL-confirmed patients.

MATERIAL AND METHODS

T-cell markers and T-cell proliferation/capacities (differentiation, activation and death) were analyzed for phenotype in 9 patients (6 F, 3 M, aged from 18 to 72 years).

RESULTS

Mean counts of CD4 and CD8 subsets were significantly decreased, 174+/-123/microl and 134+/-77/microl compared with controls, 858+/-260/microl and 482+/-164/microl, respectively (p<0.0001). Significant depletion of naive (CD45RA(+) CD62L(+)) CD4(+) T cells was noted, with a mean expression of 7+/-4% compared with controls, 45+/-1% (p<0.0001). Both CD4(+) and CD8(+) T-cell mean subsets were activated as assessed by their proportion expressing the late activation markers HLA-DR, 18+/-7% and 19+/-9% compared with controls, 6+/-3% and 10+/-6%, respectively (p<0.0001 and p<0.01). The mean expression of CD95/Fas on CD4(+) T cells was significantly higher in patients than in controls, 83+/-16% versus 45+/-13% (p<0.0001). No major abnormality of T-cell proliferation/capacities was observed.

CONCLUSIONS

Our results suggest that the T-cell loss in PIL patients is probably due to various mechanisms including enteric lymphocytes loss and activation of residual T cells, leading to death. Moreover, this loss is not compensated by a sufficient increase in T-cell thymic production.

Primary intestinal lymphangiectasia (Waldmann's disease)

Primary intestinal lymphangiectasia (PIL) is a rare disorder characterized by dilated intestinal lacteals resulting in lymph leakage into the small bowel lumen and responsible for protein-losing enteropathy leading to lymphopenia, hypoalbuminemia and hypogammaglobulinemia. PIL is generally diagnosed before 3 years of age but may be diagnosed in older patients. Prevalence is unknown. The main symptom is predominantly bilateral lower limb edema. Edema may be moderate to severe with anasarca and includes pleural effusion, pericarditis or chylous ascites. Fatigue, abdominal pain, weight loss, inability to gain weight, moderate diarrhea or fat-soluble vitamin deficiencies due to malabsorption may also be present. In some patients, limb lymphedema is associated with PIL and is difficult to distinguish lymphedema from edema. Exsudative enteropathy is confirmed by the elevated 24-h stool α1-antitrypsin clearance. Etiology remains unknown. Very rare familial cases of PIL have been reported. Diagnosis is confirmed by endoscopic observation of intestinal lymphangiectasia with the corresponding histology of intestinal biopsy specimens. Videocapsule endoscopy may be useful when endoscopic findings are not contributive. Differential diagnosis includes constrictive pericarditis, intestinal lymphoma, Whipple's disease, Crohn's disease, intestinal tuberculosis, sarcoidosis or systemic sclerosis. Several B-cell lymphomas confined to the gastrointestinal tract (stomach, jejunum, midgut, ileum) or with extra-intestinal localizations were reported in PIL patients. A low-fat diet associated with medium-chain triglyceride supplementation is the cornerstone of PIL medical management. The absence of fat in the diet prevents chyle engorgement of the intestinal lymphatic vessels thereby preventing their rupture with its ensuing lymph loss. Medium-chain triglycerides are absorbed directly into the portal venous circulation and avoid lacteal overloading. Other inconsistently effective treatments have been proposed for PIL patients, such as antiplasmin, octreotide or corticosteroids. Surgical small-bowel resection is useful in the rare cases with segmental and localized intestinal lymphangiectasia. The need for dietary control appears to be permanent, because clinical and biochemical findings reappear after low-fat diet withdrawal. PIL outcome may be severe even life-threatening when malignant complications or serous effusion(s) occur.

The pathology of malabsorption: current concepts

Intestinal malabsorption results from a wide variety of causes, which can most easily be organized into three groups. Maldigestion arises from problems with mixing or with digestive mediators, and includes post-gastrectomy patients and those with deficiencies of pancreatic or intestinal enzymes, or of bile salts. Mucosal and mural causes of malabsorption are abundant, and include gluten-sensitive enteropathy, tropical sprue, autoimmune enteropathy, and HIV/AIDS-related enteropathy, as well as mural conditions such as systemic sclerosis. Finally, microbial causes of malabsorption include bacterial overgrowth, Whipple's disease, and numerous infections or infestations that are most frequently seen in immunocompromised patients. An overview of the most common and interesting entities in each of these categories follows, along with a discussion of current concepts. Mucosal conditions and microbial causes of malabsorption are given special attention.

Common variable immunodeficiency: test indications and interpretations

Common variable immunodeficiency (CVID) is a primary immunodeficiency disorder that can present with multiple phenotypes, all of which are characterized by hypogammaglobulinemia, in a person at any age. A specific genetic defect that accounts for all CVID phenotypes has not been identified, and it is likely that several distinct genetic disorders with similar clinical presentations are responsible for the observed variation. In this review, we summarize the known genetic mutations that give rise to hypogammaglobulinemia and how these gene products affect normal or abnormal B-cell development and function, with particular emphasis on CVID. Additionally, we describe specific phenotypic and genetic laboratory tests that can be used to diagnose CVID and provide guidelines for test interpretation and subsequent therapeutic intervention.

Successful treatment of protein-losing enteropathy induced by intestinal lymphangiectasia in a liver cirrhosis patient with octreotide: a case report

A 47-yr-old man with hepatitis B virus associated liver cirrhosis was admitted to our hospital with diarrhea and generalized edema and diagnosed as protein-losing enteropathy due to intestinal lymphangiectasia by intestinal biopsy and 99m Tc albumin scan. During hospitalization, he received subcutaneous octreotide therapy. After 2 weeks of octreotide therapy, follow-up albumin scan showed no albumin leakage, and the serum albumin level was sustained. We speculate that liver cirrhosis can be a cause of intestinal lymphangiectasia and administration of octreotide should be considered for patients with intestinal lymphangiectasia whose clinical and bio-chemical abnormalities do not respond to a low-fat diet.

Acute chylothorax in children: selective retention of memory T cells and natural killer cells

OBJECTIVE

To assess for immunodeficiency in patients with hypogammaglobulinemia in the setting of draining acute chylothorax.

STUDY DESIGN

Humoral and cellular immunity was evaluated in 8 patients with chylothorax. Chylous fluid was also analyzed to document cellular losses. Data regarding clinical course and immunologic characteristics were reviewed retrospectively.

RESULTS

All patients had hypogammaglobulinemia (IgG=179+/-35 mg/dL) as well as lymphopenia (985+/-636 cells/mm(3)). T cells were decreased and natural killer cells increased in peripheral blood. The converse was found in chylous fluid. The ratio of CD3+/CD45RA+ naive: CD3+/CD45RO+ memory T cells was greater in chyle than in peripheral blood. In vitro proliferative responses to antigens and mitogens were similar to control subjects, and previously immunized patients maintained evidence of protective vaccine-specific humoral immunity. To treat hypogammaglobulinemia, patients received intravenous immunoglobulin (IVIG) to maintain IgG within normal range; 6 of 8 patients had serious infections before receiving IVIG compared with 4 of 8 patients during the period of IVIG administration.

CONCLUSION

Draining chylothorax resulted in IgG and lymphocyte depletion with preferential retention of memory T cells and natural killer cells in the circulation. Overall, protective-specific antibody levels and T cell function were maintained. IVIG administration did not lead to discernible protection from infectious complications in this small group of patients.

[Long-term followup of primary intestinal lymphangiectasia in the child. Six case reports]

Primary intestinal lymphangiectasia induce symptoms of protein-losing gastroenteropathy. Only very few studies evaluate the long term follow up of such patients. We reviewed six children diagnosed at 17 +/- 12 months and followed for 11 +/- 4.9 years.

CASE REPORTS

As soon as the diagnosis was made the patients were submitted to a strict low fat diet with added medium chain triglycerides and intermittent liposoluble vitamins perfusions. The diet allowed the disappearance of symptoms for all the patients but laboratory findings indicated continuing chyle leak for most of the children. Only one child who had normal biological parameters tolerates a normal diet since four years. Relaxation of the diet by two patients who had moderate hypoalbuminemia and lymphopenia led to severe clinical relapses 14 and 17 years after the diagnosis period with therapeutic difficulties. Three patients with long term strict low fat diet remain asymptomatic.

CONCLUSION

In most asymptomatic patients, the underlying lymphatic defect remains with permanent biological abnormalities. Clinical relapses may be severe and difficult to treat; thus the need for dietary treatment appears to be permanent.

Proteus syndrome and immunodeficiency

A 10 year old boy with Proteus syndrome presented with a pericardial effusion of unknown aetiology. Immunological investigation revealed low serum IgG and IgA, accompanied by low levels of specific antibodies to pneumococcal and haemophilus type B polysaccharides. Circulating lymphocyte surface marker profile revealed T and B cell lymphopenia. This is the first report of hypogammaglobulinaemia occurring in the Proteus syndrome.

Plasma immunoglobulins in patients with severe ovarian hyperstimulation syndrome

OBJECTIVE

To assess immunoglobulin (Ig) concentrations in plasma and ascitic fluid of patients with severe ovarian hyperstimulation syndrome (OHSS).

DESIGN

Controlled clinical study.

SETTING

Tertiary medical center.

PATIENT(S)

Ten patients with severe OHSS after ovulation induction for IVF and 10 controls who had undergone similar ovulation induction and did not develop OHSS.

INTERVENTION(S)

Three blood samples were obtained from each OHSS patient: one at the time of hospitalization for severe OHSS, one when significant clinical improvement was evident, and one at the first follow-up visit after discharge from the hospital. Blood samples were drawn from control patients 6-8 days after ET. Ascitic fluid was obtained from all patients with OHSS by therapeutic paracentesis.

MAIN OUTCOME MEASURE(S)

Immunoglobulin concentrations were assayed by radial immunodiffusion.

RESULT(S)

Significantly lower levels of gamma-globulins, specifically IgG and IgA, were detected in the plasma of patients with severe OHSS, whereas alpha- and beta-globulin levels as well as IgM levels were not significantly different from those in controls. Both IgG and IgA levels increased as patients clinically improved. Ascitic fluid contained high IgG, moderate IgA, and negligible IgM levels.

CONCLUSION

Severe OHSS is characterized by hypogammaglobulinemia, attributed to leakage of medium-molecular-weight immunoglobulins such as IgG and IgA to the peritoneal cavity.

Intestinal lymphangiectasia, a disease characterized by selective loss of naive CD45RA+ lymphocytes into the gastrointestinal tract

Intestinal lymphangiectasia (InL) is a disease characterized by hypoproteinemia and lymphocytopenia resulting from blocked intestinal lymphatics and loss of lymph fluid into the gastrointestinal tract. This leads to immunologic abnormalities including hypogammaglobulinemia, skin anergy and impaired allograft rejection. In the present study, we evaluated whether the above immunologic abnormalities are secondary to a quantitative or qualitative disorder of T cells. In initial studies we demonstrated that adult InL patients' peripheral blood contain strikingly (and significantly) reduced numbers of CD4+/CD45RA+ T cells, whereas the numbers of CD4+/CD45RO+ T cells were only moderately (and not significantly) reduced. In addition, the CD4+/CD45RO+ T cell population contained an increased percentage of highly differentiated and previously sensitized cells, as demonstrated by decreased CD27 and CD31 expression and increased HLA-DR and CD69 expression. In subsequent functional studies, we showed that the InL CD4+/CD45RO+ T cells, when stimulated in vitro, proliferate fivefold less than control CD4+/CD45RO+ T cells and produce fourfold more IL-4 and threefold less IFN-gamma and IL-2. Thus, this cytokine production profile also reflects the highly differentiated nature of the residual cell population. Overall, these studies provide new information on the trafficking of naive/mature and Th1/Th2 T cell populations in this disease model.

Adjuvant therapy of pancreatic cancer using monoclonal antibodies and immune response modifiers

Pancreatic cancer is a devastating disease with poor survival. At present, no effective adjuvant or palliative therapies are available. Unresponsiveness to chemotherapy, radiotherapy, and antihormonal treatment is one of the reasons that pancreatic cancer patients have an overall median survival time of 4-6 mo. This article summarizes clinical trials on immunotherapy of pancreatic cancer using the murine monoclonal antibodies (MAbs) 17-1A and BW 494. In addition, the use of MAb treatment in combination with immune response modifiers is discussed. In four clinical trials, MAb 17-1A was given by iv infusion to 100 patients with pancreatic cancer. In 30 of the these patents, antibody treatment was accompanied by gamma-interferon, also given intravenously. Complete response, partial response, and stable disease were reported in 1,5, and 23 patients, respectively. Passive immunotherapy using the MAb BW 494 was carried out in 148 pancreatic cancer patients in two phase I and two phase II trials. In 1 out of 75 patients a partial response and in 25 out of 74 patients stable disease were reported. However, in a controlled randomized trial enrolling 61 patients following Whipple resection, comparable survival times in patients with and without MAb BW 494 treatment led to the termination of further clinical trials with this antibody. New clinical studies using humanized MAbs in combination with immune response modifiers should be initiated to further evaluate immunotherapy as a treatment option in pancreatic cancer.