Chimeric antigen receptor macrophages target and resorb amyloid plaques.

Substantial evidence suggests a role for immunotherapy in treating Alzheimer's disease (AD). While the precise pathophysiology of AD is incompletely understood, clinical trials of antibodies targeting aggregated forms of ß amyloid (Aß) have shown that reducing amyloid plaques can mitigate cognitive decline in patients with early-stage AD. Here, we describe what we believe to be a novel approach to target and degrade amyloid plaques by genetically engineering macrophages to express an Aß-targeting chimeric antigen receptor (CAR-Ms). When injected intrahippocampally, first-generation CAR-Ms have limited persistence and fail to significantly reduce plaque load, which led us to engineer next-generation CAR-Ms that secrete M-CSF and self-maintain without exogenous cytokines. Cytokine secreting "reinforced CAR-Ms" have greater survival in the brain niche and significantly reduce plaque load locally in vivo. These findings support CAR-Ms as a platform to rationally target, resorb, and degrade pathogenic material that accumulates with age, as exemplified by targeting Aß in AD.

Evaluating inhaler education interventions for hospitalized children with asthma: A randomized controlled trial.

BACKGROUND: Most children with asthma have poor inhaler technique, with detrimental morbidity effects. Guidelines recommend clinicians provide inhaler education at every opportunity, yet resources are limited. A low-cost, technology-based intervention-Virtual Teach-to-Goal (V-TTG)-was developed to deliver tailored inhaler technique education with high fidelity. OBJECTIVE: To evaluate whether V-TTG leads to less inhaler misuse among children with asthma who are hospitalized vs brief intervention (BI, reading steps aloud). METHODS: A single-center randomized controlled trial of V-TTG vs BI was conducted with 5-to-10-year-old children with asthma hospitalized between January 2019 and February 2020. Inhaler technique was assessed pre- and post-education using 12-step validated checklists (misuse: < 10 steps correct). RESULTS: Among 70 children enrolled, mean age was 7.8 years (SD = 1.6). Most (86%) were Black. Most had an emergency department visit (94%) or hospitalization (90%) in the previous year. At baseline, nearly all children misused inhalers (96%). The proportion of children with inhaler misuse decreased significantly in V-TTG (100%→74%, P = .002) and BI (92%→69%, P = .04) groups, with no difference between groups at both time points (P = .2 and .9). On average, children performed 1.5 more steps correctly (SD = 2.0), with greater improvement with V-TTG (mean [SD] = 1.7 [1.6]) vs BI (mean [SD] = 1.4 [2.3]), though not significant (P = .6). Concerning pre and post technique, older children were significantly more likely than younger children to show more correct steps (mean change = 1.9 vs 1.1, P = .002). CONCLUSION: A technology-based intervention for tailored inhaler education led to improved technique among children, similarly to reading steps aloud. Older children saw greater benefits. Future studies should evaluate the V-TTG intervention across diverse populations and disease severities to identify the greatest impact. CLINICAL TRIAL REGISTRATION: NCT04373499.

Behavioral and electrophysiological evidence for the differential functions of TRPV1 at early and late stages of chronic inflammatory nociception in rats.

We previously reported that vanilloid receptor type 1 (VR1, or TRPV1) was up-regulated in dorsal root ganglion (DRG) and the spinal dorsal horn after chronic inflammatory pain produced by complete Freund's adjuvant (CFA) injection into the plantar of rat hind paw. In the present study, we found that subcutaneous or intrathecal application of capsazepine (CPZ), a TRPV1 competitive antagonist, could inhibit thermal hyperalgesia on day 1 and on day 14 but not on day 28 after CFA injection. With extracellular electrophysiological recording, the effect of CPZ on noxious electrical or heat stimulation evoked responses of wide dynamic range (WDR) neurons in the deep layers of the spinal dorsal horn was evaluated. Under noxious electrical stimulation to sciatic nerve, CPZ applied to the spinal cord produced an inhibition on Adelta- and C-fiber evoked responses of WDR neurons on day 1 and 14, but not on day 28. Under radiant heat stimulation to the receptive field skin, subcutaneous application of CPZ significantly inhibited the background activity and extended the response latency of WDR neurons on day 14. These results provide new evidence for the functional significance of TRPV1 at the early stage, but not the late stage, in the rat model of CFA-induced inflammatory pain.

Roles of 5-hydroxytryptamine (5-HT) receptor subtypes in the inhibitory effects of 5-HT on C-fiber responses of spinal wide dynamic range neurons in rats.

5-Hydroxytryptamine (5-HT; serotonin) plays an important role in the descending control of nociception. 5-HT and its receptors have been extensively studied in the modulation of nociceptive transmission at the spinal level using behavioral tests that may be affected by the effects of 5-HT on motor performance and skin temperature. Using electrophysiological methods, the present study aimed to systematically investigate the roles of 5-HT receptor subtypes on the inhibitory effects of 5-HT on responses of the spinal wide dynamic range (WDR) neurons to C-fiber inputs in rats. Under basal conditions, topical application of 5-HT to the spinal cord inhibited the C-fiber responses of WDR neurons dose-dependently, whereas antagonists of 5-HT(1A) [WAY 100635 [N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-2-pyridinyl-cyclohexanecarboxamide maleate salt]], 5-HT(1B) [GR 55562 [3-[3-(dimethylamino)propyl]-4-hydroxy-N-[4-(4-pyrid-dinyl)phenyl]benzamide dihydrochloride]], 5-HT(2A) [ketanserin [3-[2-[4-(fluorobenzoyl)-1-piperidinyl]ethyl]-2,4[1H,3H]-quinazolinedione tartrate]], 5-HT(2C) [RS 102221 [8-[5-(2,4-dimethoxy-5-(4-trifluoromethylphenylsulfonamido)phenyl-5-oxopentyl]-1,3,8-triazaspiro[4.5]decane-2,4-dione hydrochloride]], 5-HT(3) [MDL 72222 [3-tropanyl-3,5-dichlorobenzoate]], and 5-HT(4) [GR 113808 ([1-[2-[(methylsulfonyl)-amino]ethyl]-4-piperidinyl]methyl 1-methyl-1H-indole-3-carboxylate)] had no effect on their own. The inhibitory effects of 5-HT were reversed by antagonists of 5-HT(1B) (GR 55562), 5-HT(2A) (ketanserin), 5-HT(2C) (RS 102221), 5-HT(3) (MDL 72222), and 5-HT(4) (GR 113808) but not by 5-HT(1A) (WAY 100635) receptor antagonists. Topical administration of agonists of 5-HT(1A) [(2R)-(+)-8-hydroxy-2-(di-n-propylamino)tetralin hydrobromide], 5-HT(1B) [CGS 12066 [7-trifluoromethyl-4-(4-methyl-1-piperazinyl)pyrrolo-[1,2-a]quinoxaline maleate salt]], 5-HT(2A) (alpha-methyl-5-hydroxytryptamine maleate), 5-HT(2C) [MK 212 [6-chloro-2-(1-piperazinyl)pyrazine hydrochloride]], 5-HT(3) [1-(3-chlorophenyl)biguanide hydrochloride], and 5-HT(4) [2-[1-(4-piperonyl)piperazinyl]benzothiazole] also inhibited the C-responses. These results suggest that, under basal conditions, there is no tonic serotonergic inhibition on the C-responses of dorsal horn neurons, and multiple 5-HT receptor subtypes including 1B, 2A, 2C, 3, and 4 may be involved in mediating the inhibitory effects of 5-HT.

Comparison of the effect of intrathecal endomorphin-1 and endomorphin-2 on spinal cord excitability in rats.

We examined and compared the effects of intrathecal (i.t.) endomorphin-1 and endomorphin-2 on the nociceptive flexor reflex in decerebrate, spinalized, unanesthetized rats. I.t. endomorphin-1 and -2 induced a dose-dependent depression of the flexor reflex with an initial brief facilitatory effect. The magnitude of reflex facilitation and depression was similar between endomorphin-1 and -2, but the duration of depression was significantly longer for endomorphin-1 than endomorphin-2. The results suggested that the spinal antinociceptive effects of endomorphin-1 and -2 are similar, with endomorphin-1 being more resistant to enzymatic degradation.

Intrathecal [Nphe1]nociceptin( 1-13)NH2 selectively reduces the spinal inhibitory effect of nociceptin.

The effects of intrathecal (i.t.) application of the proposed nociceptin receptor antagonist [Nphe1]nociceptin(1-13)NH2 on the flexor reflex was evaluated in spinalized rats. I.t. [Nphe1]nociceptin (1-13)NH2 dose-dependently facilitated the flexor reflex with no depression. Pretreatment with 16.5 nmol of [Nphe1]nociceptin(1-13)NH2 prevented the development of reflex depression following 0.55 nmol i.t. nociceptin, but strongly enhance the initial excitatory effect of nociceptin. The reflex depressive effect of i.t. endomorphine-2 was not blocked by [Nphe1]nociceptin(1-13)NH2 pretreatment. It is concluded that [Nphe1]nociceptin(1-13)NH2 is a selective antagonist of the spinal receptor mediating the inhibitory action of nociceptin. It can be further suggested that the spinal inhibitory effect of nociceptin may be tonically active.

Anti-hyperalgesic and anti-allodynic effects of intrathecal nociceptin/orphanin FQ in rats after spinal cord injury, peripheral nerve injury and inflammation.

We examined the effects of intrathecal nociceptin, the endogenous ligand for the orphan opioid receptor-like receptor, on abnormal pain-related behaviors in rats after carrageenan-induced inflammation and photochemically-induced peripheral nerve or spinal cord ischemic injury. Intrathecal nociceptin dose-dependently alleviated mechanical and cold allodynia-like behavior in the two models of neuropathic pain. The heat hyperalgesia associated with peripheral inflammation was also significantly reduced, although the efficacy of the antihyperalgesic effect of nociceptin in the inflammation model was decreased. Intrathecal nociceptin also induced significant antinociception on the tail-flick test in all three groups of rats. However, the antinociceptive effect of nociceptin was significantly reduced in rats with peripheral nerve injury. These results indicated that spinally administered nociceptin has anti-allodynic and anti-hyperalgesic effects in animal models of tonic or chronic pain of different origins. Peripheral inflammation and nerve injury may induce spinal plasticity which leads to altered potency and efficacy of nociceptin.