1. ALECT2 amyloidosis and the REFLECTION study
Dr. sonu manuel
Senior resident
Dept of nephrology
NIMS

2. Amylodosis Group of protein folding disorders of diverse etiology
30 protein types
Systemic or localized
MC, AL - Derived from immunoglobulin light chain
Hereditary amyloidoses - 10% of the systemic amyloidoses.
The overall renal biopsy incidence of amyloidosis ranges from 1.3 to 4%

3. LECT2 protein
Was initially purified from culture of PHA- activated human T cell leukemia (SKW-3) cells
potential chemotactic factor for human neutrophils
Chromosome 5
Expressed in liver
Multifactorial cytokine involved in
Chemotaxis
Cell proliferation
Immunomodulation
Damage/repair process
Tumor suppression
Glucose metabolism
Phytohemagluttinin, Leucocyte chemotactic factor 2

4. ALECT2 Amyloidosis derived from leukocyte cell–derived chemotaxin
Recent studies have established ALECT2 as the second or third most common cause of renal amyloidosis
Indiana USA, azotemia nephrotic syndrome and hd , us biopsy seris of 285 cases, after AL (immunoglobulin light chain amyloidosis) and/or AA (serum protein A amyloidosis) 2,3

5. Ethnic Predisposition
88%–92% of Hispanics - Mexican descent
Indians(Punjab)
egyptians
? familial amyloidosis

6. Clinical Characteristics
Incidious onset
Usually involves only kidney
Low level proteinuria
Low GFR
Fatigue
Edema
No sig cardiac, pulmonary, neural inv
iver, spleen, lung and adrenal involvement
have also been described

8. Pathogenesis Homozygous SNP exon 3 at codon 58
Guanine rather than adenine
Codes for valine rather than isoleucine
Val58Ile variant of LECT2
Have a propensity to fold abnormally
Form insoluble fibrils
Deposits in tissues.
It is possible that the change from isoleucine to valine in the LECT2 protein decreases its stability and allows it to undergo amyloidogenic conformational alterations

10. Amyloidogenic fibril protein – entire 133 residue peptide
Not all SNPs develope disease.
Not all LECT2 amyloid tissue deposits indicate LECT2 amyloidosis disease [ 3% hispanic autopsies ]

11. Diagnosis

12. Plasma LECT2 concentration in normal individuals is 19.7±3.4 ng/ml
Its serum level is increased in
liver diseases
acute liver injury
hepatocellular carcinoma
fatty liver
obesity
insulin resistance 

13. Diagnosis of nephropathy due to ALECT2 amyloidosis8
Renal biopsy
Congo-red staining
to confirm renal amyloidosis
Alternative – available at specialist centers
Liquid chromatography/ Mass spectroscopy
Immunohistochemistry (IHC)
Proteomic typing of amyloid (incl LECT2)
*Required for confirmation if negative or weak staining of amyloid by IHC
Specific immunoperoxidase staining for AA and ALECT2
Immunofluorescence for AL (κ and λ chains) *

14. AApo AI amyloidosis and AApo AIV amyloidosis - medullary interstitium
Figure 1
Section of kidney showing replacement of glomeruli with amorphous eosinophilic material AL amyloidosis and AA amyloidosis - glomeruli and vessels
AApo AI amyloidosis and AApo AIV amyloidosis - medullary interstitium
Kidney International  , DOI: ( /ki )
Copyright © 2008 International Society of Nephrology Terms and Conditions

15. Figure 2
Section of kidney stained with Congo red. (a) Congo red-stained section of kidney with marked staining in glomeruli, blood vessel walls, and interstitial tissues. Original magnification × 40. (b) When viewed under polarized light, Congo red-stained deposits give green birefringence typical of amyloid.
Kidney International  , DOI: ( /ki )
Copyright © 2008 International Society of Nephrology Terms and Conditions

16. Figure 3
Electron microscopy of renal glomerulus showing nonbranching fibrils (original magnification × 4800). Average diameter of fibrils is 10nm (original magnification (inset) × 98000).
Kidney International  , DOI: ( /ki )
Copyright © 2008 International Society of Nephrology Terms and Conditions

17. Figure 5
Section of frozen kidney treated with monoclonal anti-LECT2 antibody showing localization to glomerular and interstitial deposits. Immunofluorescence - negative
false-positive staining for IgG with/without staining for IgM, IgA, κ, and λ may rarely occur
Kidney International  , DOI: ( /ki )
Copyright © 2008 International Society of Nephrology Terms and Conditions

18. Concurrent renal disease was present in 30%
DN being the most common lesion followed by IgAN & MN
Higher proteinuria
lower renal amyloid load

19. Laser microdissection/mass spectrometry

20. I-Labelled SAP scintigraphy
: Serial SAP scintigraphy in ALECT2 amyloidosis.

21. Treatment
No available treatment
Conservative mesures
Transplant

22. Prognosis Guarded ESRD Elderly Advanced renal disease 1 out of 3
median renal survival : 62 months
Renal survival, defined as time from diagnosis to renal replacement therapy, in ALECT2 amyloidosis in comparison with other untreated renal amyloidoses, including apolipoprotein A-I amyloidosis (AApoAI), lysozyme amyloidosis (ALys) and fibrinogen A a-chain amyloidosis (AFib) amyloidosis.

23. Protein
LECT2- 16-kD cytokine
Mainly by hepatocytes
Expressed in vascular tissues, smooth muscle cells.

24. A Study of the Natural History of ALECT2* Disease
Protocol ALN-LECT2-NT-001 Sponsored by Alnylam Pharmaceuticals, Inc.
*Leukocyte Chemotactic Factor 2 Amyloidosis ClinicalTrials.gov NCT

25. The REFLECTION natural history study
The REFLECTION study is the first global study to characterize the natural history of ALECT2 amyloidosis
Seeking 150 participants
Involves a combination of retrospective clinical chart review and prospective data collection
All patients participate in retrospective portion
Only those who have not reached ESRD will participate in prospective portion
No study drug will be administered
In biannual visits physical examination, routine laboratory tests, ecg echo, usg, quality of life questioners
For use with healthcare professionals only

26. REFLECTION study: outcome measures
For use with healthcare professionals only

27. REFLECTION study: patient population
Adults > 18 years of age
Renal biopsy-proven ALECT2 amyloidosis Either:
Documented diagnosis* available at the time of consent or
Can be confirmed during screening for the study
*Historical renal biopsy samples are requested for confirmation of diagnosis and characterization of renal disease
No exclusion criteria
For use with healthcare professionals only

28. Which patients should be considered for the study?
3 groups of potential patients
*Risk factors and common features:
Racial predisposition: Hispanic, Native Americans, First Nation People from Canada, Egyptian, Sudanese, Punjabi people from Indian and Pakistan, and Chinese.
Usually diagnosed between 40 – 90 years of age; mean 65 years
Typical clinical features:
Slow rate of renal decline; mean eGFR loss of 6 mL/min/1.73 m2/year
Variable proteinuria
No haematuria or microscopic haematuria
Potential associated clinical conditions
Hepatitis B/C
Diabetes and hypertension
Patients with
Confirmed diagnosis
of ALECT2 amyloidosis 1
Priority
Patients with
Untyped Renal Amyloidosis 2
Priority
Patients with
CKD of unknown or uncertain origin, with risk factors* 3
Priority
For use with healthcare professionals only

29. Prioritization for Consideration REFLECTION
* For priority groups 5/6, study biopsy may be approved on a case-by-case basis in consultation with the Sponsor.
ǂ broad estimates based on limited data
For use with healthcare professionals only

30. For use with healthcare professionals only
References
1) Benson MD, James S, Liepnieks JJ, Kluve-Beckerman B. Leukocyte chemotactic factor 2: A novel renal amyloid protein. Kidney Int. 2008;74(2): ) Said SM, Sethi S, Valeri AM, et al. Characterization and outcomes of renal leukocyte chemotactic factor 2-associated amyloidosis. Kidney Int. 2014; 86 (2): 370–377. 3) Larsen CP, Kossmann RJ, Beggs ML, et al. Clinical, morphologic, and genetic features of renal leukocyte chemotactic factor 2 amyloidosis. Kidney Int. 2014; 86 (2): ) Larsen CP, et al. Leukocyte chemotactic factor 2 amyloidosis (ALECT2) is a common form of renal amyloidosis among Egyptians. Modern Pathology. 2016; 29: 416–420. 5) Rezk T, et al. Diagnosis, pathogenesis and outcome in leucocyte chemotactic factor 2 (ALECT2) amyloidosis. Nephrology Dialysis Transplantation. 2018; 33(2): 241–247 6) Picken M. Alect2 amyloidosis: primum non nocere (first, do no harm). Kidney International. 2014; 86 (2): ) Lan F et al. LECT2 functions as a hepatokine that links obesity to skeletal muscle insulin resistance. Diabetes. 2014; 63(5): ) Nasr SH, Dogan, A, Larson CP. Leukocyte Cell–Derived Chemotaxin 2–Associated Amyloidosis: A Recently Recognized Disease with Distinct Clinicopathologic Characteristics. Clin J Am Soc Neph. 2015; 10 (11)
For use with healthcare professionals only

31. THANK YOU