Table 3. Cluster of differentiation 68 (CD68).
| First author | Brain bank | N | Sex | Age | AD genetic risk factors | AD histologically confirmed and criteria | Braak stage | C history of neurological or psychiatric disease | PMI (h) | Brain region | Technique | Direction of results |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Alvarez87 | NR | AD: 24 (for cortex and CA1) ADaβ−: 5 Control: 24 (16 for cortex and CA1) | NR | AD: 70–86 ADaβ−: 70-76 Control: 70-86 | NR | Braak, CERAD Adaβ− group had no aβ pathology | AD: V–VI | No mental disorder | NR | Cerebellar cortex and hippocampus white matter molecular layer, Purkinje cell layer, granule cell layer, white matter core of the folium, central white matter, layer V of the cortex and CA1 | IHC | ↔ Between AD, Adaβ− and control |
| Arnold86 | University of Pennsylvania Alzheimer Disease Center Core | AD: 10 C: 14 | AD: 5/5 C: 6/8 | AD: 81.8 C: 75.3 | NR | Khachaturian | NR | No major psychiatric illness, no neuropathologic abnormality except 1 patient with lacunar infarct, one with small temporal contusions | AD: 9.8 C: 11.4 | Calcarine cortex (BA17), enthorinal cortex (BA 28) hippocampus CA1, midfrontal cortex (BA9 and 46) orbitofrontal cortex (BA11), subiculum | IHC | ↑ In all regions |
| Arnold79 | AD and FTD from: University of Pennsylvania’s Alzheimer Disease Center Core | AD: 10 C: 10 | AD:5/5 C: 4/6 | AD: 81.8 C: 76.1 | NR | Yes | NR | No history of major neurological or psychiatric disorder, no neuropathologic abnormalities relevant to mental status | AD: 9.8 C: 11.6 | Calcarine cortex, frontal lobe, hippocampus | IHC | ↑ (Not compared statistically) |
| Bachstetter69 | University of Kentucky Alzheimer's Disease Center | AD:7 C: 9 | AD: 4/3 C: 6/3 | AD: 77 C: 86 | APOE: AD: NA: 2 4/4: 1 3/4: 2 C: 3/4: 1 | CERAD | AD: Median VI C: Median II | NR | AD: 4.2 C: 2.4 | Hippocampus: CA1, CA2/3, CA4, DG, subiculum and adjacent white matter. Morphology assessed in the CA1 only | IHC | ↑ CD68 staining in subiculum, CA1, DG, and mean of hippocampal regions ↔ in CA2/3, CA4 or white matter ↔ in CD68+ amoeboid in any region except ↑ DG |
| Dal Bianco20 | NR | AD: 9 C: 15 | AD: 0/9 C: 13/2 | AD: 81 C: 70 | NR | Braak, CERAD | AD: IV: 2, V: 4, VI: 3 | No neurological disease or brain lesions | NR | Cortical areas of the temporal lobe, including entorhinal cortex, hippocampus and temporal cortex | Immunocytochemistry | ↑ CD68 near plaque only |
| DeLuca80 | Oxford Brain Bank | AD: 4 C: 8 | AD: 3/1 C: 5/3 | AD: 76.3 C: 63.0 | NR | NR | AD: V or VI | No neurological disease | NR | Olfactory bulb/tract | IHC | ↑ In parenchyma and meninges ↔ Perivascular |
| Doorn81 | NBB or Department of Pathology, Vrije Universiteit, University Medical Center in Amsterdam, The Netherlands | AD: 8 C: 11 | AD: 3/5 C: 5/6 | AD: 74.5 C: 84 | NR | Braak | NFT AD: IV–VI C: 0–III Amyloid: AD: C: 7 B: 1 C: 0:4 A: 3 B: 3 C: 1 | Without neurological or psychiatric diseases | AD: 6.2 C: 5.9 | Olfactory bulb | IHC | ↑ Amoeboid microglia ↔ Ramified |
| Falke88 | University of Pennsylvania ARDC | AD: 12 C: 11 | AD: 2/10 C: 7/4 | AD: 79.4 C: 77.6 | NR | NR | NR | No neuropsychiatric disease—3 control subjects had abnormality at autopsy (haemorrhagic microinfarct, bilateral contusion, adenocarcinoma metastasis). 1 AD subject had microinfarct, all had aβ plaques and NFT | AD: 10.9 C: 12.4 | Caudate nucleus (6 AD, 7 Control), mediodorsal nucleus of the thalamus (12 AD, 10 Control) | IHC | ↔ In caudate nucleus ↔ In MEDIODORSAL nucleus of the thalamus (P=0.06) |
| Fiala78 | UCLA ADRC Brain Bank | AD: 8 C: 5 | NR | AD: 77.6 C: 74.6 | NR | Yes, one patient with vascular dementia not excluded | NR | No neuropathological findings | All 5–6 h | Mix of areas (different for different cases): hippocampus, frontal lobe (mix of left and right), superior temporal lobe | IHC | ↑ CD68 staining in AD than C |
| Hoozemans17 | NBB | Braak stage 0: 5, I–II: 16, III–IV: 10, V–VI: 9 | Braak stage 0: 3/2, I–II: 6/10, III–IV: 0/10,V–VI: 3/6 | Braak stage 0: 62, I–II: 83, III–IV: 89, V–VI: 76 | NR | Braak | Subjects vary from 0–VI (not divided into C and AD) | NR | Braak stage 0: 8, I–II: 7.5, III–IV: 6.5, V–VI: 5 | Temporal cortex | IHC | ↑ With increasing Braak NFT or plaque stage (P<0.05 for trend), significant for NFT group V–VI vs 0 |
| Hoozemans28 | Netherlands Brain Bank | AD: 19 C:19 | AD: 3/16 C: 8/11 | AD: 83.5, C: 76.8 | APOE4: AD: 12 C: 8 | Braak | AD: avg IV C: avg I | NR | AD: 5.1 C: 8.6 | Midtemporal cortex | IHC | ↑ ↑ In AD patients <80 years compared with those >80 years |
| Hultman82 | KPBBB, Duke University, North Carolina | AD: 36 C: 22 | AD: 13/23 C: 10/12 | AD: 76.9 C: 79.1 | APOE4 Carriers: AD: 14 C: 0 | CERAD, NIA-Reagan criteria | AD: III: 11, IV: 3, V: 13, VI: 9 C: I: 18, II: 3, III: 1 | NR, some cases and Cs had mild to severe atherosclerosis | AD: 9.2 C: 7.7 | Frontal cortex—perivascular | IHC | ↑ |
| Kellner18 | NR | AD: 48 C: 48 | AD: 19/29 C: 24/24 | AD: 80.3 C: 77.5 | NR | Braak, CERAD | AD: II–VI (38>4) C: I–III (45=0) | NR | NR | Entorhinal, frontal cortex, temporal cortex | IHC | ↑ |
| Lue89 | BSHRI | AD: 16 C: 21 | NR | NR | NR | NR | NR | NR | All avg 3.1 | Mixed: corpus callosum, superior and middle frontal gyri of the right hemisphere | IHC | ↔ |
| Minett56 | Medical Research Council Cognitive Function and Ageing Study—six centres in UK | AD: 83 C: 130 | AD: 64/53 C: 51/66 | AD: 89 C: 84 | NR | CERAD | NR | NR | NR | Middle frontal gyrus (BA9) | IHC | ↑ Negative correlation with cognition (MMSE), positively with AD pathology (plaques, tangles) |
| Perez-Nievas83 | Massachusetts General Hospital, Mayo Clinic and University of Pittsburgh ADRC Brain Banks | AD:15 LPC: 15 IPC: 12 HPC: 8 | NR | AD: 87.2 LPC: 84.4 IPC: 89.8 HPC: 88.4 | NR | Braak, CERAD | NR | NR | NR | Superior temporal sulcus | IHC, stereology | ↑ In AD vs LPC, IPC and HPC ↔ in IPC or HPC vs C |
| Rezaie41 | MRC London Neurodegenerative Diseases Brain Bank | AD: 10 C: 10 | AD: 4/6 C: 7/3 | AD: 79.3 C: 70.2 | NR | CERAD | NR | No history of neurological disease or neuropathology | AD: 20.9, C: 43.2 | Frontal blocks included agranular- intermediate frontal cortex (BA 6/8), cingulate cortex (BA 24/32) Occipital blocks included the calcarine sulcus (BA 17) and striate cortex) | IHC | ↑ In frontal white matter, occipital white matter, plaque associated frontal grey matter, plaque associated occipital grey matter ↔ Frontal grey matter, or occipital grey matter |
| Sanchez-Mejias76 | Tissue bank at Fundación CIEN | Braak stage 0: 8, II: 13, III–IV: 9, V–VI: 17 | Braak stage 0: 5/3, II: 7/13, III–IV: 4/5, V–VI: 7/11 | Braak stage 0: 19, II: 78, III–IV: 80, V–VI: 79 | NR | Braak Braak V–VI clinically classified as AD, Braak II age-matched and used as C | Braak stage 0: 8, II: 13, III–IV: 9, V–VI: 17 | NR | Braak stage 0: 8, II: 7, III–IV: 6, V–VI: 8 | Hippocampus CA1, CA3, parahippocampal gyrus | PCR | ↑ With increasing Braak stage Braak stage V–VI had clinical AD and were compared with stage II Cs |
| Serrano-Pozo84 | Massachusetts ADRC Brain Bank | AD: 91 C: 15 | AD: 33/58 C: 5/10 | AD: 79.0 C: 79.9 | APOE E4 carriers AD: 59/32 C: 4/11 | NIA-Reagan Criteria | NR | NR, 10/15 had some plaque burden | AD: 13.9 C: 22.3 | Temporal association isocortex (BA 38) | IHC, stereology | ↑ With increasing disease stage and NFT, no correlation with amyloid burden |
| Van Everbroeck85 | NR | AD: 21 C: 40 | NR | NR | NR | Yes | NR | NR, 14 cases/Cs suffered from inflammatory conditions | NR | Mixed: Cerebellum (when available), frontal, occipital and temporal cortices | IHC | ↑ |
| Wojtera51 | NR | AD: 4 C: 2 | AD: 4 C: 2 | NR | NR | NIA-Reagan Criteria | NR | NR | NR | Mixed: cerebellum, cerebral cortex | IHC | ↔ Microglia number ↔ cortex and cerebellum ↔ in HLA-DR/CD68 ratio between AD and control (activation) |
Abbreviations: AD, Alzheimer’s disease; ADRC, Alzheimer’s Disease Research Center; APOE, apolipoprotein E; Avg, average; BSHRI, Banner Sun Health Research Institute; BA, Brodmann area; C, Control; CA, Cornu ammonis; CD, cluster of differentiation; CERAD, Consortium to Establish a Registry for Alzheimer’s Disease; CIEN, Centro Investigación Enfermedades Neurológicas; DG, dentate gyrus; FTD, frontotemporal dementia; HLA, human leukocyte antigen; HPC, high pathology control; IHC, immunohistochemistry; IPC, intermediate pathology control; KPBBB, Kathleen Price Bryan Brain Bank; LPC, low pathology control; MRC, Medical Research Council; NA, not available; NBB, Netherlands Brain Bank; NFT, neurofibrillary tangle; NIA, National Institute on Aging; NR, not reported; PMI, post-mortem interval; UCLA, University of California Los Angeles.
Results are expressed relative to control unless specified otherwise. Where there are both young and older controls, values are reported for the older (age-matched controls).