Autophagy activity and expression pattern of autophagy-related markers in the podocytes of patients with lupus nephritis: association with pathological classification

Figures & data

Table 1. Relationship between LN pathological types and clinical manifestations.

Clinical data	LN pathological types						Total
	Type II (n = 15)	Type III (n = 15)	Type IV (n = 15)	Type V (n = 15)	Type V + III (n = 15)	Type V + IV (n = 15)
Gender
Male	1	1	2	3	0	2	9
Female	14	14	13	12	15	13	81
Age (year)	26.2 ± 9.9	28.4 ± 10.5	28.7 ± 11.5	33.3 ± 10.5	25.40 ± 10.7	33.6 ± 11.9	30.5 ± 10.5
Clinical type
Occult nephritis	8	0	0	0	0	0	8
Nephritic syndrome	7	13	8	5	1	1	35
Nephrotic syndrome	0	2	6	10	14	10	42
Rapidly progressing glomerulonephritis	0	0	1	0	0	4	5
Total	15	15	15	15	15	15	90

Table 2. Renal manifestations of patients.

	II (n = 15)	III (n = 15)	IV (n = 15)	V (n = 15)	V + III (n = 15)	V + IV (n = 15)
Hypertension	2 (13.3)	4 (26.7)	7 (46.7)	3 (20.0)	4 (26.7)	7 (46.7)
Hematuria	3 (20.0)	9 (60.0)	12 (80.0)	5 (33.3)	10 (66.7)	12 (80.0)
Macrohematuria	0	1 (6.7)	2 (13.3)	0	1 (6.7)	1 (6.7)
Urine protein ≥ 0.5 g/day	11 (73.3)	13 (86.7)	14 (93.3)	14 (93.3)	14 (93.3)	15 (100.0)
sCr ≥1.3 mg/dL	0	1 (6.7)	5 (33.3)	1 (6.7)	2 (13.3)	4 (26.7)

For each data in the table, the number outside the parentheses was the number of the patients positive for the specific manifestation; the number inside the parentheses was the percentage of the patients positive for the specific manifestation in each classification group.

Table 3. The serum autoantibody manifestations of patients.

	II (n = 15)	III (n = 15)	IV (n = 15)	V (n = 15)	V + III (n = 15)	V + IV (n = 15)
ANA	14 (93.3)	12 (80.0)	14 (93.3)	11 (73.3)	13 (86.7)	13 (86.7)
A-dsDNA	7 (46.7)	7 (46.7)	10 (66.7)	4 (26.7)	5 (33.3)	9 (60.0)
A-Sm	4 (26.7)	3 (20.0)	4 (26.7)	3 (20.0)	3 (20.0)	3 (20.0)
A-RNP	4 (26.7)	4 (26.7)	4 (26.7)	3 (20.0)	6 (40.0)	4 (26.7)
ANCA	0	1 (6.7)	1 (6.7)	0	0	0
SSA	4 (26.7)	7 (46.7)	5 (33.3)	6 (40.0)	6 (40.0)	6 (40.0)
SSB	1 (6.7)	3 (20.0)	2 (13.3)	2 (13.3)	3 (20.0)	2 (20.0)
Low C3	8 (53.3)	11 (73.3)	12 (80.0)	8 (53.3)	11 (73.3)	13 (86.7)
Low C4	2 (13.3)	7 (46.7)	7 (46.7)	2 (13.3)	3 (20.0)	7 (46.7)

For each data in the table, the number outside the parentheses was the number of the patients positive for the specific manifestation; the number inside the parentheses was the percentage of the patients positive for the specific manifestation in each classification group.

Table 4. The comparison of the data for the podocyte fusion between different pathological classifications of LN.

The data for the podocyte fusion in different types of LN
Type	II (n = 15)	III (n = 15)	IV (n = 15)	V (n = 15)	V + III (n = 15)	V + IV (n = 15)
Mean ± SD	57.0 ± 10.8	29.7 ± 7.4	42.0 ± 12.5	60.7 ± 16.8	55.0 ± 11.0	56.3 ± 13.3
Comparison between groups (p-value)
Type	II	III	IV	V	V + III	V + IV
II		0.000	0.002	0.175	0.620	0.881
III			0.003	0.000	0.000	0.000
IV				0.002	0.005	0.005
V					0.284	0.440
V + III						0.767

All date expressed as number (percentage).

Figure 1. Quantification of podocytes containing autophagosomes in kidney sections from 90 LN patients and 15 healthy controls; the percentage of autophagosome-positive podocytes in LN biopsies was significantly higher than in controls (p < 0.0001).

Figure 2. Autophagosomes (arrows) detected by EM in the podocytes of LN patients and controls.

Figure 3. The comparison of the number of autophagosomes in podocytes between the various types of LN.

Table 5. Autophagosomes in podocytes from LN patients.

Group	Number	Autophagosomes/podocyte
Control	15	3 (2, 5)
LN	90	3 (2, 5)
Type II	15	2 (1, 2)
Type III	15	5 (3, 6)
Type IV	15	4 (3, 5)
Type V	15	2 (1, 2)
Type V–III	15	3 (3, 4)
Type V–IV	15	4 (3, 5)

The data were demonstrated in the form of M(P25, P75).

Figure 4. Representative findings on immunohistochemical staining of renal biopsy specimens from patients with LN with antibodies against Beclin1, microtubule-associated protein light chain 3 (LC3), and UNC-51-like kinase 1 (ULK1) autophagy-related gene 7 (Atg7). The arrows pointed to the positive signals.

Table 6. Correlation of biomarkers associated with autophagy in the various LN types.

Variables	Beclin 1 expression (%)			LC3 expression (%)			ULK1 expression (%)			ATG7 expression (%)
	Weak	Strong	p-Value	Weak	Strong	p-Value	Weak	Strong	p-Value	Weak	Strong	p-Value
Control	10 (66.7)	5 (33.3)		11 (73.3)	4 (26.7)		9 (60.0)	6 (40.0)		11 (73.3)	4 (26.7)
LN II type	14 (93.3)	1 (6.7)	0.042	15 (100.0)	0 (0.0)	0.1000	15 (100.0)	0 (0.0)	0.017	15 (100.0)	0 (0.0)	0.1000
LN III type	3 (20.0)	12 (80.0)	0.025	4 (26.7)	11 (73.3)	0.027	2 (13.3)	13 (86.7)	0.021	3 (20.0)	12 (80.0)	0.009
LN IV type	1 (6.7)	14 (93.3)	0.002	0 (0.0)	15 (100.0)	<0.0001	2 (13.3)	13 (86.7)	0.021	1 (6.7)	14 (93.3)	<0.0001
LN V type	15 (100.0)	0 (0.0)	0.042	15 (100.0)	0 (0.0)	0.1000	15 (100.0)	0 (0.0)	0.017	14 (93.3)	1 (6.7)	0.330
LN V + III type	11 (73.3)	4 (26.7)	1.000	10 (66.7)	3 (20.0)	1.000	12 (80.0)	3 (20.0)	0.427	11 (73.3)	4 (26.7)	1.000
LN V + IV type	3 (20.0)	12 (80.0)	0.025	3 (20.0)	12 (80.0)	0.009	1 (6.7)	14 (93.3)	0.005	2 (13.3)	13 (86.7)	0.003

For each data in the table, the number outside the parentheses was the number of the patients positive for the specific proteins; the number inside the parentheses was the percentage of the patients positive for the specific proteins in each classification group.