Journal o f Clinical Immunology, Vol. 12, No. 3, 1992
Elevated Serum Interleukin-6 Levels in Patients with Acute Hepatitis YEQING SUN, 1 KATSUTOSHI TOKUSHIGE, 1 ETSUKO ISONO, 1 KATSUMI YAMAUCHI, 1'2 and HIROSHI OBATA ~
Accepted: December 2, 1991
released from these cells, and hence a precise characterization of these cytokines seems to be important for further understanding the mechanism of various human diseases. In this regard, recent reports of abnormal behavior of these cytokines in certain human diseases are thought to be important for understanding in detail the mechanism of these diseases (12-15). One of these was that patients with fulminant hepatitis have a high level of serum interleukin-1 (IL-1) and tumor necrotizing factor (TNF) (15). These results suggest that analysis of these cytokines may help give us some understanding of the mechanisms of various liver diseases. In the present study, we focused on the analysis of the serum IL-6 level in acute hepatitis and reported the possible rote of IL-6 in these diseases.
To study the mechanisms of hepatocyte injury, we examined serum interleukin-6 (IL-6) level in acute hepatitis patients. Based on their clinical features, these patients were divided into three groups, acute hepatitis (AH), severe acute hepatitis, and fulminant hepatic failure (FHF). The present study demonstrated that, in association with their clinical status, their serum IL-6 levels were gradually increased (16.5 --- 14.5 pg/ml in AH, 26.3 --- 19.0 pg/ml in severe AH, and 470.2 +-- 26t.4 pg/ml in FHF; control level, 5.2 __+0.6 pg/ml). Furthermore, we found that a significant correlation between serum IL-6 level and prothrombin time existed in these patients and that the elevated serum IL-6 returned to a normal range after recovery from their hepatocyte injury. Thus, our study demonstrates that the serum IL-6 level is a possible marker for identifying the clinical status in acute hepatitis and that this cytokine may have some roles in hepatocyte injury.
PATIENTS AND METHODS
KEY WORDS: Interleukin-6; acute hepatitis; hepatocyte injury; fulminant hepatic failure; prothrombin time.
Patients
INTRODUCTION
Subjects studied were 15 acute hepatitis patients and 21 healthy controls. Based on their clinical features, these patients were divided into three groups: acute hepatitis (AH), severe acute hepatitis (severe AH), and fulminant hepatic failure (FHF) (Table I). AH and severe AH were divided based on their prothrombin time (PTT); the patients having low levels of t ~ T (less than 40%) were classified as severe AH. The clinical features of F H F were identical to the definition in a previous study (16). The etiology of these patients was as follows: hepatitis A virus (HAV) infection for two AH and two severe A H patients, hepatitis B virus (HBV) infection for two AH patients, non-A, non-B hepatitis (NANB) for two AH, two severe AH, and one F H F patients, and drug-induced F H F for two and
Since it is widely predicted (1, 2) that the immune response plays important roles in the generation of various liver diseases, several immunological features in patients with such diseases have been investigated. Those studies included examinations of functions as well as the proportion of various immunocompetent cells in peripheral blood and in the liver (3-9). A recent development in molecular immunology demonstrates (10, 11) that the immune response is also regulated by a variety of cytokines 1Division of Medicine, Institute of Gastroenterology, Tokyo Women's Medical College, 8-1, Kawada-cho, Shinjuku-ku, Tokyo, Japan. 2To whom correspondence should be addressed.
197 0271-9142/92/0500-0197506.50/0© 1992PlenumPublishingCorporation
198
SUN, TOKUSHIGE, ISONO, YAMAUCHI, AND OBATA
Table I. Clinical Features and Serum IL-6 Level of Patients Studied
Patient No.
9 10 11 12 13 14 15 Normal range
Etiology
PTT (%)
Consciousness disturbance (coma)
HAV a HAV HBV b HBV NANB c NANB HAV HAV NANB NANB Malignant lymphoma Malignant lymphoma Drug (halothane) Drug NANB
100.0 56.0 58.7 86.0 100.0 100.0 26.0 39.0 38.0 36.0 30.0 10.0 15.0 5.0 35.0
No No No No No No No No No No II II III IV IV
Diagnosis AH AH AH AH All AH Severe Severe Severe Severe FHF FHF FHF FHF FHF
AH AH AH AH
IL-6 (pg/ml) 5 11 41 32 5 5 46 14 48 5 280 480 101 840 650
Mean + SD
16.3 -+ 13.6
26.3 +- 19.0
470.2 +- 261.4 5.2 + 0.6
aHepatitis A virus. bHepatitis B virus. CNeither hepatitis A virus nor hepatitis B virus infection was demonstrated.
malignant lymphoma for another two FHF patients. Histological studies of AH and severe AH patients revealed that all these patients had histological features compatible with AH. Measurement of Serum IL-6 Levels All serum samples were obtained from these patients when they were admitted to our hospital. These sera and control sera were kept at -80°C until assay. The IL~6 titers in these sera were assayed by a newly developed enzyme-linked immunosorbent assay (ELISA) system (Fuji Revio Co., Tokyo).
Statistical Analysis Statistical analysis was done by Student's t test. A P value less than 0.05 was reported as significant. An inverse correlation coefficient was done between serum IL-6 level and prothrombin (PT) level (%) in both severe AH and FHF.
level, whereas the others had a normal range of s e ~ m IL-6. The mean value of these AH patients was 16.5 --- 14.5 pg/ml, higher than that of the controls (P < 0.01). In severe AH patients, the IL-6 level was increased in three of four patients (mean, 28.3 --- 19.0 pg/ml; P < 0.01 compared with controis). The most remarkable difference was observed in F H F patients. Their IL-6 levels ranged from 10I to 840 pg/ml (mean, 470.2 --- 261.4 pg/ml). The IL-6 value in F H F patients was significantly higher than that of controls (P < 0.001) and that of the other two patient groups (P < 0.001 in both studies). In addition, the difference between AH patients and controls as well as that between severe AH patients and controls was also statistically significant (P < 0.001 in both studies). Thus, our study demonstrated that in association with the clinical status, these patients' serum IL-6 was elevated.
Reverse Association Between IL-6 and PTT RESULTS
Serum IL-6 Level in Acute Hepatitis Patients Using an ELISA system, we found that serum IL-6 levels in all healthy subjects were less than 15 pg/ml (mean --- SD, 5.2 - 0.6 pg/ml). As shown in Table I, three of six AH patients had a high IL-6
The association between the clinical features and the serum !L-6 was investigated further by the relationship between serum IL-6 level and prothrombin time in both severe AH and F H F patients. The results shown in Fig. 1 indicate that the association between serum IL-6 level and PTT was significant (P < 0.02).
Journal of Clinical Immunology, 11ol. 12, No. 3, 1992
199
IL-6 IN ACUTE HEPATITIS PATIENTS
IL-6
hence it was predicted that quantitative analysis of the serum IL-6 level in various liver diseases would be important in understanding in detail the mechanisms of these liver diseases. For this reason, using a newly established ELISA system, we quantified serum IL-6 levels in acute hepatitis patients. As shown in Table I, the serum IL-6 level was increased in three of Six AH patients, three of four severe AH patients, and all FHF patients. Based on their clinical conditions, the mean IL-6 level was gradually increased (Table I). These results suggested that the elevation in IL-6 was associated with the patients' clinical conditions. This was also supported by the following two results; (i) an inverse association between IL-6 level and PT time was observed (Fig. 1), and (ii) IL-6 was increased only in the acute phase, and not in the recovery phase (Table II). Therefore, from these results, we think that IL-6 is a useful marker for identifying the clinical Status in these patients. Particularly, as Shown in Table I, a high level of serum IL-6 (more than 100 pg/ml) existed in all FHF patients but not in the other patients. These results indicate that measurement of serum IL-6 is particuiarly useful for the early diagnosis of FHF. It is well documented (23) that the production of IL-6 is caused by stimulation of IL-6-producing cells with I L 4 and/or tumor necrosis factor (TNF). In this regard, a recent report by Muto et aI. (t5) is important. They reported that many FHF patients have a high serum IL-i and TNF level. Based on these results, we think that a high level of serum IL-1 and/or TNF stimulates T cells and results in hyperproduction of IL-6 in these patients. Our results demonstrated that the serum IL-6 level was increased in malignant lymphoma (cases 11 and 12 in Table I), in which the immune response may not be responsible for their hepatocyte injury. Therefore, we think that hyperproduction of these cytokines is the result of a rapid impairment of the hepatocytes. However, we have recently found that peripheral blood T cells obtained from B-type
1000 ~900 F 800
Y = - 4 . 7 3 X +402.51 (r = -0,582)
700 600 500 400 300 200 I00 •
0
10
20
•
30
40
•
50
60
•
70
80
~
90 100 PT ( ~ )
Fig. 1. Reverse association between serum IL-6 level and PTT. All patients were analyzed for the relation between IL-6 levels and prothrombin time in this study. A significant association was observed (r = -0.582, n = 15, P < 0.023).
Serial Study o f Serum IL-6 in Three Severe A H Patients
A strong association between the level of serum IL-6 and the clinical status was also confirmed by serial studies of the serum IL-6 level in three severe AH patients. As shown in Table II, the elevated serum IL-6 level returned to a normal range (14.0 to 7.0 pg/ml in case 1, 46.0 to 5.6 pg/ml in case 2, and 48.0 to 5.0 pg/ml in case 3) in the recovery phase. It can therefore be concluded that the elevation in serum IL-6 was closely associated with the patients' clinical conditions. DISCUSSION Interleukin-6 (IL-6), originally identified as T cell replacing factor (TRF) by Muraguchi et al. (17), is reported to have a variety of biological functions, such as (i) B cell stimulating activity (18), (ii) colony stimulating activity (19), (iii) neuron cell differentiating activity (20), and (iv) plasma cell stimulating activity (21). Furthermore, it was also reported (22) that IL-6 act as a hepatocyte stimulating factor, and
Table II. Comparison of Serum IL-6 Levels and PTT in Acute and Recovery Phases ~
Acute phase Case No.
Diagnosis
1 2 3
Severe AH Severe AH Severe AH
Etiology HAV HAV NANB
°Control serum IL-6 level was 5.2 -+ 0.6 pg/ml.
Journal of Clinical Immunology, Vol. 12, No. 3, 1992
Recovery phase
PTT (%)
IL-6 (pg/ml)
PTT (%)
IL-6 (pg/ml)
39.0 26.0 38.0
14.0 46.0 48.0
100.0 100.0 i00.0
7.0 5.6 5.0
200
chronic hepatitis patients have specific cytotoxic activity against HBV-DNA-transfected human myeloma cells (Kamogawa et al., submitted for publication). After precultivation of these CTL with IL-6, their cytotoxic activity was greatly increased (unpublished observation). Thus, in at least some situations, it can be predicted that the high level of serum IL-6 enhances the immune response and results in accelerating hepatocyte injury. In conclusion, our present studies demonstrate that several AH patients, particular FHF patients, have high levels of serum IL-6 and that the elevation of IL-6 is correlated with their clinical status.
SUN, TOKUSHIGE,ISONO, YAMAUCHI,AND OBATA
12.
13.
14.
15.
REFERENCES 1. Biischenfelde K-HMZ, Manns M: Mechanisms of autoimmune liver disease. Semin Liver Dis 4:26-35, 1984 2. Van Hattum J, Van Oudenaren A, Schalm SW, Visser JWM, Benner R: T-lymphocyte subpopulation in patients with various courses after hepatitis B virus infection. Scand J Gastroenterol 19:497-501, 1984 3. Hodgson HJ, Wands JR, Isselbacher KJ: Alteration in suppressor cell activity in active chronic hepatitis. Proc Natl Acad Sci USA 75:1549-1551, 1978 4. Thestrup-Peterson K, Ladefoged K, Andresen L: Lymphocyte transformation test with liver specific protein and phytohemagglutinin in patients with liver disease. Clin Exp Immunol 24:1-7, 1976 5. Wands JR, Perrotto JL, Alpert E, Isselbacher KJ: Cellmediated immunity in acute and chronic hepatitis. J Clin Invest 55:921-929, 1975 6. Thomson AD, Cochrane MA, McFarlane IG, Eddleston AL, Williams R: Lymphocyte cytotoxicity to isolated hepatocyte in chronic active hepatitis. Nature 252:721-722, 1974 7. Thomas HC, Brown D, LaBrooy J, Epstein O: T cell subsets in autoimmune and HBV-induced chronic liver disease. A review of the abnormalities and the effects of treatment. Liver 2:266-269, 1982 8. Carella G, Chatenoud L, Degos F, Bach MA: Regulatory T cell subset imbalance in chronic active hepatitis. J Clin Immunol 2:93-100, 1982 9. Hasegawa K, Yamauchi K, Furukawa T, Obata H: Dual color fluorescence analysis of peripheral T cell subsets in hepatitis B virus-induced liver disease. Hepatology 8:11341137, 1988 10. Kishimoto T: Factors affecting B cell growth and differentiation. Annu Rev Immunol 3:133-157, 1985 11. Hirano T, Taga T, Yasukawa K, Nakajima K, Nakano N, Takatsuki F, Shimizu M, et al.: Human B-cell differentiation factor defined by an anti-peptide antibody and its possible
16. 17.
18.
19.
20.
21.
22.
23.
role in autoantibody production. Proc Natl Acad Sci USA 84:228-231, 1987 Hirano T, Matsuda T, Turner M, Miyasaka N, Buchan G, Tang B, Sato K, et al.: Excessive production of interleukin-6/B cell stimulatory factor-2 in rheumatoid arthritis. Eur J Immunol 18:1797-1801, 1988 Kawano M, Hirano T, Matsuda T, Taga T, Horii Y, Iwata K, Asaoku H, et al.: Autocrine generation and requirement of BSF-2/IL-6 for human multiple myelomas. Nature 332:8385, 1988 Yoshizaki K, Matsuda T, Nishimoto N, Kuritani T, Taeho L, Aozasa K, Nakahata T, et al.: Pathogenic significance of interleukin-6 (IL-6/BSF-2) in castieman's disease. Blood 74:1360-1367, 1989 Muto Y, Nouri-Aria KT, Meager A, Alexander GJM, Eddleston AL, Williams R: Enhanced tumor necrosis factor and interleukin-1 in fulminant hepatic failure. Lancet 9:7274, 1988 Trey C, Davidson C: The management of fulminant hepatic failure. Prog Liver Dis 3:282-298, 1970 Muraguchi A, Kishimoto T, Miki Y, Kuritani T, Kaieda T, Yoshizaki K, Yamamura Y: T cell-replacing factor ffRF) induced IgG secretion in a human B blastoid cell line and demonstration of acceptors for TRF. J Immunol 127:412416, 1981 Hirano T, Yasukawa K, Harada H, Taga T, Watanabe Y, Matsuda T, Kashiwamura S, et al.: Complementary DNA for a novel human interleukin (BSF-2) that induces B lymphocytes to produce immunoglobulin. Nature 324:73-76, 1986 Bot FJ, Eijk L, Broeders L, Aarden LA, Ltwenberg B: Interleukin-6 synergizes with M-CSF in the formation of macrophage colonies from purified human marrow progenitor cells. Blood 73:435-437, 1989 Satoh T, Nakamura S, Taga T, Matsuda T, Hirano T, Kishimoto T, Kaziro Y: Induction of neuronal differentiation in PC12 cells by B-cell stimulatory factor 2/interleukin-6. Mol Cell Biol 8:3546-3549, 1988 Van Damme J, Opdenakker G, Simpson RJ, Rubira MR, Cayphas S, Vink A, Billiau A, et al.: Identification of the human 26-KD protein. Interferon 132 (IFN-132), as a B cell hybridoma/plasmacytoma growth factor induced by interleukin 1 and tumor necrosis factor. J Exp Med 165:914-919, 1987 Gauldie J, Richards C, Harnish D, Lansdorp P, Baumann H: Interferon 132/Bcell stimulatory factor type 2 shares identity with monocyte-derived hepatocyte-stimulating factor and regulates the major acute phase protein response in liver cells. Proc Natl Acad Sci USA 84:7251-7255, 1987 Defilippi P, Poupart P, Tavernier J, Fiers W, Content J: Induction and regulation of mRNA encoding 26-KDa protein in human cell lines treated with recombinant human tumor necrosis factor. Proc Natl Acad Sci USA 84:4557-4561, 1987
Journal o f Clinical Immunology, Vol. 12, No. 3, 1992
Elevated Serum Interleukin-6 Levels in Patients with Acute Hepatitis YEQING SUN, 1 KATSUTOSHI TOKUSHIGE, 1 ETSUKO ISONO, 1 KATSUMI YAMAUCHI, 1'2 and HIROSHI OBATA ~
Accepted: December 2, 1991
released from these cells, and hence a precise characterization of these cytokines seems to be important for further understanding the mechanism of various human diseases. In this regard, recent reports of abnormal behavior of these cytokines in certain human diseases are thought to be important for understanding in detail the mechanism of these diseases (12-15). One of these was that patients with fulminant hepatitis have a high level of serum interleukin-1 (IL-1) and tumor necrotizing factor (TNF) (15). These results suggest that analysis of these cytokines may help give us some understanding of the mechanisms of various liver diseases. In the present study, we focused on the analysis of the serum IL-6 level in acute hepatitis and reported the possible rote of IL-6 in these diseases.
To study the mechanisms of hepatocyte injury, we examined serum interleukin-6 (IL-6) level in acute hepatitis patients. Based on their clinical features, these patients were divided into three groups, acute hepatitis (AH), severe acute hepatitis, and fulminant hepatic failure (FHF). The present study demonstrated that, in association with their clinical status, their serum IL-6 levels were gradually increased (16.5 --- 14.5 pg/ml in AH, 26.3 --- 19.0 pg/ml in severe AH, and 470.2 +-- 26t.4 pg/ml in FHF; control level, 5.2 __+0.6 pg/ml). Furthermore, we found that a significant correlation between serum IL-6 level and prothrombin time existed in these patients and that the elevated serum IL-6 returned to a normal range after recovery from their hepatocyte injury. Thus, our study demonstrates that the serum IL-6 level is a possible marker for identifying the clinical status in acute hepatitis and that this cytokine may have some roles in hepatocyte injury.
PATIENTS AND METHODS
KEY WORDS: Interleukin-6; acute hepatitis; hepatocyte injury; fulminant hepatic failure; prothrombin time.
Patients
INTRODUCTION
Subjects studied were 15 acute hepatitis patients and 21 healthy controls. Based on their clinical features, these patients were divided into three groups: acute hepatitis (AH), severe acute hepatitis (severe AH), and fulminant hepatic failure (FHF) (Table I). AH and severe AH were divided based on their prothrombin time (PTT); the patients having low levels of t ~ T (less than 40%) were classified as severe AH. The clinical features of F H F were identical to the definition in a previous study (16). The etiology of these patients was as follows: hepatitis A virus (HAV) infection for two AH and two severe A H patients, hepatitis B virus (HBV) infection for two AH patients, non-A, non-B hepatitis (NANB) for two AH, two severe AH, and one F H F patients, and drug-induced F H F for two and
Since it is widely predicted (1, 2) that the immune response plays important roles in the generation of various liver diseases, several immunological features in patients with such diseases have been investigated. Those studies included examinations of functions as well as the proportion of various immunocompetent cells in peripheral blood and in the liver (3-9). A recent development in molecular immunology demonstrates (10, 11) that the immune response is also regulated by a variety of cytokines 1Division of Medicine, Institute of Gastroenterology, Tokyo Women's Medical College, 8-1, Kawada-cho, Shinjuku-ku, Tokyo, Japan. 2To whom correspondence should be addressed.
197 0271-9142/92/0500-0197506.50/0© 1992PlenumPublishingCorporation
198
SUN, TOKUSHIGE, ISONO, YAMAUCHI, AND OBATA
Table I. Clinical Features and Serum IL-6 Level of Patients Studied
Patient No.
9 10 11 12 13 14 15 Normal range
Etiology
PTT (%)
Consciousness disturbance (coma)
HAV a HAV HBV b HBV NANB c NANB HAV HAV NANB NANB Malignant lymphoma Malignant lymphoma Drug (halothane) Drug NANB
100.0 56.0 58.7 86.0 100.0 100.0 26.0 39.0 38.0 36.0 30.0 10.0 15.0 5.0 35.0
No No No No No No No No No No II II III IV IV
Diagnosis AH AH AH AH All AH Severe Severe Severe Severe FHF FHF FHF FHF FHF
AH AH AH AH
IL-6 (pg/ml) 5 11 41 32 5 5 46 14 48 5 280 480 101 840 650
Mean + SD
16.3 -+ 13.6
26.3 +- 19.0
470.2 +- 261.4 5.2 + 0.6
aHepatitis A virus. bHepatitis B virus. CNeither hepatitis A virus nor hepatitis B virus infection was demonstrated.
malignant lymphoma for another two FHF patients. Histological studies of AH and severe AH patients revealed that all these patients had histological features compatible with AH. Measurement of Serum IL-6 Levels All serum samples were obtained from these patients when they were admitted to our hospital. These sera and control sera were kept at -80°C until assay. The IL~6 titers in these sera were assayed by a newly developed enzyme-linked immunosorbent assay (ELISA) system (Fuji Revio Co., Tokyo).
Statistical Analysis Statistical analysis was done by Student's t test. A P value less than 0.05 was reported as significant. An inverse correlation coefficient was done between serum IL-6 level and prothrombin (PT) level (%) in both severe AH and FHF.
level, whereas the others had a normal range of s e ~ m IL-6. The mean value of these AH patients was 16.5 --- 14.5 pg/ml, higher than that of the controls (P < 0.01). In severe AH patients, the IL-6 level was increased in three of four patients (mean, 28.3 --- 19.0 pg/ml; P < 0.01 compared with controis). The most remarkable difference was observed in F H F patients. Their IL-6 levels ranged from 10I to 840 pg/ml (mean, 470.2 --- 261.4 pg/ml). The IL-6 value in F H F patients was significantly higher than that of controls (P < 0.001) and that of the other two patient groups (P < 0.001 in both studies). In addition, the difference between AH patients and controls as well as that between severe AH patients and controls was also statistically significant (P < 0.001 in both studies). Thus, our study demonstrated that in association with the clinical status, these patients' serum IL-6 was elevated.
Reverse Association Between IL-6 and PTT RESULTS
Serum IL-6 Level in Acute Hepatitis Patients Using an ELISA system, we found that serum IL-6 levels in all healthy subjects were less than 15 pg/ml (mean --- SD, 5.2 - 0.6 pg/ml). As shown in Table I, three of six AH patients had a high IL-6
The association between the clinical features and the serum !L-6 was investigated further by the relationship between serum IL-6 level and prothrombin time in both severe AH and F H F patients. The results shown in Fig. 1 indicate that the association between serum IL-6 level and PTT was significant (P < 0.02).
Journal of Clinical Immunology, 11ol. 12, No. 3, 1992
199
IL-6 IN ACUTE HEPATITIS PATIENTS
IL-6
hence it was predicted that quantitative analysis of the serum IL-6 level in various liver diseases would be important in understanding in detail the mechanisms of these liver diseases. For this reason, using a newly established ELISA system, we quantified serum IL-6 levels in acute hepatitis patients. As shown in Table I, the serum IL-6 level was increased in three of Six AH patients, three of four severe AH patients, and all FHF patients. Based on their clinical conditions, the mean IL-6 level was gradually increased (Table I). These results suggested that the elevation in IL-6 was associated with the patients' clinical conditions. This was also supported by the following two results; (i) an inverse association between IL-6 level and PT time was observed (Fig. 1), and (ii) IL-6 was increased only in the acute phase, and not in the recovery phase (Table II). Therefore, from these results, we think that IL-6 is a useful marker for identifying the clinical Status in these patients. Particularly, as Shown in Table I, a high level of serum IL-6 (more than 100 pg/ml) existed in all FHF patients but not in the other patients. These results indicate that measurement of serum IL-6 is particuiarly useful for the early diagnosis of FHF. It is well documented (23) that the production of IL-6 is caused by stimulation of IL-6-producing cells with I L 4 and/or tumor necrosis factor (TNF). In this regard, a recent report by Muto et aI. (t5) is important. They reported that many FHF patients have a high serum IL-i and TNF level. Based on these results, we think that a high level of serum IL-1 and/or TNF stimulates T cells and results in hyperproduction of IL-6 in these patients. Our results demonstrated that the serum IL-6 level was increased in malignant lymphoma (cases 11 and 12 in Table I), in which the immune response may not be responsible for their hepatocyte injury. Therefore, we think that hyperproduction of these cytokines is the result of a rapid impairment of the hepatocytes. However, we have recently found that peripheral blood T cells obtained from B-type
1000 ~900 F 800
Y = - 4 . 7 3 X +402.51 (r = -0,582)
700 600 500 400 300 200 I00 •
0
10
20
•
30
40
•
50
60
•
70
80
~
90 100 PT ( ~ )
Fig. 1. Reverse association between serum IL-6 level and PTT. All patients were analyzed for the relation between IL-6 levels and prothrombin time in this study. A significant association was observed (r = -0.582, n = 15, P < 0.023).
Serial Study o f Serum IL-6 in Three Severe A H Patients
A strong association between the level of serum IL-6 and the clinical status was also confirmed by serial studies of the serum IL-6 level in three severe AH patients. As shown in Table II, the elevated serum IL-6 level returned to a normal range (14.0 to 7.0 pg/ml in case 1, 46.0 to 5.6 pg/ml in case 2, and 48.0 to 5.0 pg/ml in case 3) in the recovery phase. It can therefore be concluded that the elevation in serum IL-6 was closely associated with the patients' clinical conditions. DISCUSSION Interleukin-6 (IL-6), originally identified as T cell replacing factor (TRF) by Muraguchi et al. (17), is reported to have a variety of biological functions, such as (i) B cell stimulating activity (18), (ii) colony stimulating activity (19), (iii) neuron cell differentiating activity (20), and (iv) plasma cell stimulating activity (21). Furthermore, it was also reported (22) that IL-6 act as a hepatocyte stimulating factor, and
Table II. Comparison of Serum IL-6 Levels and PTT in Acute and Recovery Phases ~
Acute phase Case No.
Diagnosis
1 2 3
Severe AH Severe AH Severe AH
Etiology HAV HAV NANB
°Control serum IL-6 level was 5.2 -+ 0.6 pg/ml.
Journal of Clinical Immunology, Vol. 12, No. 3, 1992
Recovery phase
PTT (%)
IL-6 (pg/ml)
PTT (%)
IL-6 (pg/ml)
39.0 26.0 38.0
14.0 46.0 48.0
100.0 100.0 i00.0
7.0 5.6 5.0
200
chronic hepatitis patients have specific cytotoxic activity against HBV-DNA-transfected human myeloma cells (Kamogawa et al., submitted for publication). After precultivation of these CTL with IL-6, their cytotoxic activity was greatly increased (unpublished observation). Thus, in at least some situations, it can be predicted that the high level of serum IL-6 enhances the immune response and results in accelerating hepatocyte injury. In conclusion, our present studies demonstrate that several AH patients, particular FHF patients, have high levels of serum IL-6 and that the elevation of IL-6 is correlated with their clinical status.
SUN, TOKUSHIGE,ISONO, YAMAUCHI,AND OBATA
12.
13.
14.
15.
REFERENCES 1. Biischenfelde K-HMZ, Manns M: Mechanisms of autoimmune liver disease. Semin Liver Dis 4:26-35, 1984 2. Van Hattum J, Van Oudenaren A, Schalm SW, Visser JWM, Benner R: T-lymphocyte subpopulation in patients with various courses after hepatitis B virus infection. Scand J Gastroenterol 19:497-501, 1984 3. Hodgson HJ, Wands JR, Isselbacher KJ: Alteration in suppressor cell activity in active chronic hepatitis. Proc Natl Acad Sci USA 75:1549-1551, 1978 4. Thestrup-Peterson K, Ladefoged K, Andresen L: Lymphocyte transformation test with liver specific protein and phytohemagglutinin in patients with liver disease. Clin Exp Immunol 24:1-7, 1976 5. Wands JR, Perrotto JL, Alpert E, Isselbacher KJ: Cellmediated immunity in acute and chronic hepatitis. J Clin Invest 55:921-929, 1975 6. Thomson AD, Cochrane MA, McFarlane IG, Eddleston AL, Williams R: Lymphocyte cytotoxicity to isolated hepatocyte in chronic active hepatitis. Nature 252:721-722, 1974 7. Thomas HC, Brown D, LaBrooy J, Epstein O: T cell subsets in autoimmune and HBV-induced chronic liver disease. A review of the abnormalities and the effects of treatment. Liver 2:266-269, 1982 8. Carella G, Chatenoud L, Degos F, Bach MA: Regulatory T cell subset imbalance in chronic active hepatitis. J Clin Immunol 2:93-100, 1982 9. Hasegawa K, Yamauchi K, Furukawa T, Obata H: Dual color fluorescence analysis of peripheral T cell subsets in hepatitis B virus-induced liver disease. Hepatology 8:11341137, 1988 10. Kishimoto T: Factors affecting B cell growth and differentiation. Annu Rev Immunol 3:133-157, 1985 11. Hirano T, Taga T, Yasukawa K, Nakajima K, Nakano N, Takatsuki F, Shimizu M, et al.: Human B-cell differentiation factor defined by an anti-peptide antibody and its possible
16. 17.
18.
19.
20.
21.
22.
23.
role in autoantibody production. Proc Natl Acad Sci USA 84:228-231, 1987 Hirano T, Matsuda T, Turner M, Miyasaka N, Buchan G, Tang B, Sato K, et al.: Excessive production of interleukin-6/B cell stimulatory factor-2 in rheumatoid arthritis. Eur J Immunol 18:1797-1801, 1988 Kawano M, Hirano T, Matsuda T, Taga T, Horii Y, Iwata K, Asaoku H, et al.: Autocrine generation and requirement of BSF-2/IL-6 for human multiple myelomas. Nature 332:8385, 1988 Yoshizaki K, Matsuda T, Nishimoto N, Kuritani T, Taeho L, Aozasa K, Nakahata T, et al.: Pathogenic significance of interleukin-6 (IL-6/BSF-2) in castieman's disease. Blood 74:1360-1367, 1989 Muto Y, Nouri-Aria KT, Meager A, Alexander GJM, Eddleston AL, Williams R: Enhanced tumor necrosis factor and interleukin-1 in fulminant hepatic failure. Lancet 9:7274, 1988 Trey C, Davidson C: The management of fulminant hepatic failure. Prog Liver Dis 3:282-298, 1970 Muraguchi A, Kishimoto T, Miki Y, Kuritani T, Kaieda T, Yoshizaki K, Yamamura Y: T cell-replacing factor ffRF) induced IgG secretion in a human B blastoid cell line and demonstration of acceptors for TRF. J Immunol 127:412416, 1981 Hirano T, Yasukawa K, Harada H, Taga T, Watanabe Y, Matsuda T, Kashiwamura S, et al.: Complementary DNA for a novel human interleukin (BSF-2) that induces B lymphocytes to produce immunoglobulin. Nature 324:73-76, 1986 Bot FJ, Eijk L, Broeders L, Aarden LA, Ltwenberg B: Interleukin-6 synergizes with M-CSF in the formation of macrophage colonies from purified human marrow progenitor cells. Blood 73:435-437, 1989 Satoh T, Nakamura S, Taga T, Matsuda T, Hirano T, Kishimoto T, Kaziro Y: Induction of neuronal differentiation in PC12 cells by B-cell stimulatory factor 2/interleukin-6. Mol Cell Biol 8:3546-3549, 1988 Van Damme J, Opdenakker G, Simpson RJ, Rubira MR, Cayphas S, Vink A, Billiau A, et al.: Identification of the human 26-KD protein. Interferon 132 (IFN-132), as a B cell hybridoma/plasmacytoma growth factor induced by interleukin 1 and tumor necrosis factor. J Exp Med 165:914-919, 1987 Gauldie J, Richards C, Harnish D, Lansdorp P, Baumann H: Interferon 132/Bcell stimulatory factor type 2 shares identity with monocyte-derived hepatocyte-stimulating factor and regulates the major acute phase protein response in liver cells. Proc Natl Acad Sci USA 84:7251-7255, 1987 Defilippi P, Poupart P, Tavernier J, Fiers W, Content J: Induction and regulation of mRNA encoding 26-KDa protein in human cell lines treated with recombinant human tumor necrosis factor. Proc Natl Acad Sci USA 84:4557-4561, 1987
Journal o f Clinical Immunology, Vol. 12, No. 3, 1992
