Pharmacological Activities of Lonicerae japonicae flos and Its Derivative-"Chrysoeriol" in Skin Diseases

Chrysoeriol is an active ingredient derived from the Chinese medicinal herb (CMH) "Lonicerae japonicae flos" in the dried flower bud or bloomed flower of Lonicera japonica Thunberg. Dermatoses are the most common diseases in humans, including eczema, acne, psoriasis, moles, and fungal infections, which are temporary or permanent and may be painless or painful. Topical corticosteroids are widely used in Western medicine, but there are some side effects when it is continuously and regularly utilized in a large dosage. Chrysoeriol is a natural active ingredient, nontoxic, and without any adverse reactions in the treatment of dermatological conditions.

METHODS

Nine electronic databases were searched, including WanFang Data, PubMed, Science Direct, Scopus, Web of Science, Springer Link, SciFinder, and China National Knowledge Infrastructure (CNKI), without regard to language constraints. The pharmacological activities of chrysoeriol from Lonicerae japonicae flos to fight against skin diseases were explained and evaluated through the literature review of either in vitro or in vivo studies.

RESULTS

Chrysoeriol decreased the mRNA levels of proinflammatory cytokines IL-6, IL-1β, and TNF-α. These were transcriptionally regulated by NF-κB and STAT3 to combat skin inflammation. It also showed promising actions in treating many skin ailments including wound healing, depigmentation, photoprotection, and antiaging.

CONCLUSION

The cutaneous route is the best delivery approach to chrysoeriol across the skin barrier. However, toxicity, dosage, and safety assessments of chrysoeriol in a formulation or nanochrysoeriol on the human epidermis for application in skin diseases must be further investigated.

Photodynamic Action of Curcumin and Methylene Blue against Bacteria and SARS-CoV-2-A Review

Coronavirus disease 19 (COVID-19) has occurred for more than four years, and the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing COVID-19 is a strain of coronavirus, which presents high rates of morbidity around the world. Up to the present date, there are no therapeutics that can avert this form of illness, and photodynamic therapy (PDT) may be an alternative approach against SARS-CoV-2. Curcumin and methylene blue have been approved and used in clinical practices as a photosensitizer in PDT for a long time with their anti-viral properties and for disinfection through photo-inactivated SARS-CoV-2. Previously, curcumin and methylene blue with antibacterial properties have been used against Gram-positive bacteria, Staphylococcus aureus (S. aureus), and Gram-negative bacteria, Escherichia coli (E. coli), Enterococcus faecalis (E. faecalis), and Pseudomonas aeruginosa (P. aeruginosa).

METHODS

To conduct a literature review, nine electronic databases were researched, such as WanFang Data, PubMed, Science Direct, Scopus, Web of Science, Springer Link, SciFinder, and China National Knowledge Infrastructure (CNKI), without any regard to language constraints. In vitro and in vivo studies were included that evaluated the effect of PDT mediated via curcumin or methylene blue to combat bacteria and SARS-CoV-2. All eligible studies were analyzed and summarized in this review.

RESULTS

Curcumin and methylene blue inhibited the replication of SARS-CoV-2. The reactive oxygen species (ROS) are generated during the treatment of PDT with curcumin and methylene blue to prevent the attachment of SARS-CoV-2 on the ACE2 receptor and damage to the nucleic acids either DNA or RNA. It also modulates pro-inflammatory cytokines and attenuates the clotting effects of the host response.

CONCLUSION

The photodynamic action of curcumin and methylene blue provides a possible approach against bacteria and SARS-CoV-2 infection because they act as non-toxic photosensitizers in PDT with an antibacterial effect, anti-viral properties, and disinfection functions.

Behavioral Prevention, Treatment, and Rehabilitation of Using Western and Chinese Medicines or Herbal Products among the Public in Response to COVID-19 in Hong Kong: A Cross-Sectional Study

The coronavirus disease 2019 (COVID-19) pandemic occurred in Hong Kong for more than two years. This article conducted a cross-sectional study for participants to investigate the behavioral prevention, treatment, and rehabilitation of using Western medicines or herbal products for COVID-19 in Hong Kong. A questionnaire was designed and performed over 2 weeks from 1 May to 15 May 2022. It consisted of five parts with around 20 questions conducted including sociodemographic information, prevention, treatment, rehabilitation of COVID-19, and also the sources of information. The pattern usage of Chinese or Western medicines for COVID-19 was studied after data collection. 318 people participated in this survey, and only 311 were qualified. The sociodemographic information, e.g., personal educational level, and behavior for the prevention of COVID-19, which included wearing masks (98.7%), using alcohol hand sanitizer (83.0%), washing hands frequently (82.4%), avoiding crowds (53.1%), and staying home more often (50.6%). Western medicines, such as antipyretic drugs, antitussive drugs, and pain reliever drugs, whilst Chinese medicines, such as Lianhua Qingwen Jiaonang, Huoxiang Zhengqi San or Wan, and Nin Jiom Pei Pa Koa, were most commonly used in the treatment and rehabilitation periods of COVID-19. Herbal products, including lemon, honey, ginger, and herbal tea, were used as a daily diet to fight against COVID-19. Based on the result findings, Chinese medicines or herbal products were used during the COVID-19 pandemic, but most of the participants used an unknown Chinese medicine practitioner's prescription and self-administered Chinese medicine. The pattern of Chinese medicines and Western medicines' usage in the prevention, treatment, and rehabilitation of COVID-19 was also investigated; this showed a statistically significant association between the variables according to gender, age, and Chinese or Western medicines for further investigation.

Chinese medicinal herbs as potential prodrugs for obesity

Obesity is a leading worldwide health threat with ever-growing prevalence, it promotes the incidence of various diseases, particularly cardiovascular disease, metabolic syndrome, diabetes, hypertension, and certain cancers. Traditional Chinese Medicine (TCM) has been used to control body weight and treat obesity for thousands of years, Chinese medicinal herbs provide a rich natural source of effective agents against obesity. However, some problems such as complex active ingredients, poor quality control, and unclear therapeutic mechanisms still need to be investigated and resolved. Prodrugs provide a path forward to overcome TCM deficiencies such as absorption, distribution, metabolism, excretion (ADME) properties, and toxicity. This article aimed to review the possible prodrugs from various medicinal plants that demonstrate beneficial effects on obesity and seek to offer insights on prodrug design as well as a solution to the global obesity issues.

Cigarette smoking and glaucoma in the United States population

PurposeTo evaluate the association between cigarette smoking and glaucoma in the United States population.Patients and methodsUS civilian, non-institutionalized population from 2005 to 2008 administrations of the National Health and Nutrition Examination Survey that were ≥40 years of age with visual fields and optic disc photographs were included. Diagnosis of glaucoma was based on the Rotterdam criteria. Logistic regression modeling was performed to assess the association between glaucoma and smoking history, while controlling for age, gender, ethnicity, household income, alcohol consumption, diabetes, and hypertension.ResultsIn 3864 participants, 212 (5.5%) had glaucoma (corresponds to a population weighted glaucoma prevalence of 3.7% in a total of 83 570 127 subjects). Population weighted proportion of current smokers was 20.6% and ex-smokers was 28.3%. Participants with glaucoma were older (63.0±11.6 vs 56.1±11.2, P=0.002), likely to be male (57.1% vs 49.2%, P=0.03), to be Black (36.3% vs 20.7%, P<0.001), and to have diabetes (18.9% vs 12.4%, P=0.006) and hypertension (50.5% vs 39.7%, P=0.003). Current smokers had a lower odds of glaucoma compared to non-smokers (OR=0.61, 95% CI=0.41-0.88, P=0.009), and ex-smokers (OR=0.46, 95% CI=0.28-0.76, P=0.002). The effect estimates were similar in adjusted models, but not statistically significant. Among smokers, greater pack/day of smoking history was associated with statistically significantly higher odds of glaucoma (OR=1.70, 95% CI=1.08-2.67, P=0.02).ConclusionsAmong cigarette smokers, heavy smoking defined by greater number of pack of cigarettes smoked per day is associated with higher odds of glaucoma. Health care providers should include this association when counseling patients on their smoking habit.

Differences in the compliance with hospital infection control practices during the 2009 influenza H1N1 pandemic in three countries

BACKGROUND

In December 2009, the World Health Organization (WHO) issued updated guidelines on the prevention of H1N1 influenza virus in healthcare settings. In 2010, the WHO pandemic influenza alert level was still at phase 6.

AIM

To study the practice of infection control measures during the 2009 influenza H1N1 pandemic among healthcare workers (HCWs) in three countries.

METHODS

A standardized, self-administered anonymous questionnaire survey was conducted in 2010 among doctors, nurses and allied HCWs in 120 hospital-based clinical departments in Hong Kong, Singapore and the UK. Questions were asked on demographics; previous experience and perceived severity of influenza; infection control practices; uptake of seasonal influenza vaccination and H1N1 vaccination. Multiple logistic regression was used to test the independent association with different factors.

FINDINGS

A total of 2100 HCWs in the three countries participated. They reported high compliance (>80%) with infection control procedures regarded as standard for droplet-transmitted infections including wearing and changing gloves, and washing hands before and after patient contact. However, the reported use of masks with indirect or direct patient contact (surgical or N95 as required by their hospital) varied considerably (96.4% and 70.4% for Hong Kong; 82.3% and 87.7% for Singapore; 25.3% and 62.0% for the UK). Reported compliance was associated with job title, number of patient contacts and perceived severity of pandemics. There was no association between the uptake for seasonal or 2009 H1N1 vaccines and compliance.

CONCLUSIONS

Compliance with infection control measures for pandemic influenza appears to vary widely depending on the setting.

Intermediate-term comparison of trabeculectomy with intraoperative mitomycin-C between Asian American and Caucasian glaucoma patients: a case-controlled comparison

PURPOSE

Compare the efficacy and survival of trabeculectomy with intraoperative mitomycin-C (MMC) between Asian American and Caucasian patients in the same clinical setting.

METHODS

In total, 29 Asian American patients (29 eyes) with trabeculectomies were matched case to case with 29 Caucasian patients (29 eyes) retrospectively. Matching criteria included age, glaucoma subtype, and preoperative intraocular pressure (IOP), gender, surgeon, ocular history, and glaucoma medications. Criteria of success included: (1) Final IOP>5 and <22 mmHg, (2) IOP reduction>or=20%, or final IOP<or=10 mmHg, and (3) without additional glaucoma surgery, loss of light perception, or complication.

RESULTS

Mean follow-up durations of Asian American and Caucasian group were 40.11+/-22.5 months and 38.8+/-17.7 months, respectively (P=0.81). At the final visits, IOP decreased from 18.7+/-6.1 to 10.9+/-4.0 mmHg (P<0.0001) in the Asian American group, and from 19.0+/-5.5 to 11.0+/-3.8 mmHg (P<0.0001) in the Caucasian group. There were no significant differences between the two groups in IOP levels at 6 months, 1 year, and final visits. The probabilities of trabeculectomy survival (continuing to meet definition of success criteria) at 12 and 48 months were 75.9 and 56.6% in the Asian American group and 82.8 and 66.6% in the Caucasian group, respectively. (P=0.46) There were no significant differences for rates of surgical success, failure, complication, vision decrease, hypotony, and cataract development. Patients who had episodes of hypotony had a higher rate of diagnosis of low-tension glaucoma subtype (P=0.02).

CONCLUSIONS

In a case-controlled comparison of an intermediate-term follow-up of trabeculectomy with intraoperative MMC, Asian American patients have a similar efficacy and survival probability as Caucasian patients.

Effects of combined cataract surgery and trabeculectomy with mitomycin C on ocular dimensions

AIMS

To characterise changes in ocular dimensions after combined cataract operation and trabeculectomy with mitomycin C using separate incisions (combined operation).

METHODS

24 consecutive eyes that had combined operation and 16 eyes that had cataract operation alone were enrolled. The axial lengths before and after operations were determined with non-contact optical coherence biometry. The intraocular pressures (IOP), axial lengths, corneal curvatures, and the expected and observed refractive errors before and after operations were compared.

RESULTS

After a combined operation, mean IOP was significantly reduced from 16.6 (SD 5.8) mm Hg to 10.9 (4.1) mm Hg (p<0.00001), and mean axial length was significantly shortened from 24.10 (0.98) mm to 23.98 (0.96) mm (p<0.00001). The mean axial length reduction after combined operation (117 (57) microm) was significantly larger than the reduction after cataract operation alone (75 (38) microm, p<0.02), and correlated significantly with the postoperative IOP (p<0.002). There was a mean with the rule surgically induced corneal astigmatism of 0.44 (0.83) dioptre by vector analysis, and a significant increase of mean keratometry reading of 0.23 (0.46) dioptre after a combined operation. However, there was no significant difference between the expected and observed refractive errors.

CONCLUSIONS

Despite an alteration of the axial length and corneal curvature, the refractive outcome after a combined operation did not differ significantly from the predicted refraction.

Chimeras of the integrin beta subunit mid-region reveal regions required for heterodimer formation and for activation

A central region of the beta2 integrin subunit, RN (residues D300 to C459), was replaced by the equivalent sequences from beta1 and beta7 to give the chimeras beta2RN1 and beta2RN7. Whilst the former construct failed to form heterodimer at the cell surface with alphaL, the later of these could be expressed together with the alphaL subunit to form a variant LFA-1. Based on recent modelling work, the RN region consists of two parts, one is the C-terminal end of the putative A-domain (RB, residues D300 to A359), and the other the mid-region (BN, residues Y360 to C459). Chimeras exchanging the two component regions were made. Of the four resultant chimeras, only the beta2RB1 chimera failed to support LFA-1 expression. Thus the beta1 specific residues of this region affect the interaction with the alphaL subunit. Whereas the alphaL/beta2RB7 LFA-1 variant is wildtype like with respect to ICAM-1 adhesion, the alphaLbeta2BN1 and alphaLbeta2BN7, as well as the alphaLbeta2RN7, variants are more adhesive than the wildtype. These results suggest that an authentic beta2 mid-region is, in part, required for maintaining the LFA-1 in a resting state.

Serial axial length measurements in congenital glaucoma

PURPOSE

To illustrate the utility of axial length measurements in the management of congenital glaucoma.

METHODS

Interventional case series. Twelve eyes of six consecutive patients with congenital glaucoma were followed with serial axial length measurements. The axial growth patterns were compared with the normal growth curve.

RESULTS

Eight (66.7%) of 12 eyes had initial axial lengths longer than the normal range, and 4 eyes (33.3%) were within the normal range. After surgical intervention with good intraocular pressure control in 10 eyes, 3 eyes showed a decrease of axial length and 7 eyes showed no decrease of axial length, but the axial growth pattern paralleled the normal growth curve. After surgical intervention with poor intraocular pressure control, 2 eyes had axial growth pattern greater than the normal pattern.

CONCLUSION

With intraocular pressure control in congenital glaucoma, axial length may decrease or the axial growth pattern may parallel the normal growth curve. Axial length measurements may be useful to monitor the control of congenital glaucoma.

Characterization of four CD18 mutants in leucocyte adhesion deficient (LAD) patients with differential capacities to support expression and function of the CD11/CD18 integrins LFA-1, Mac-1 and p150,95

Leucocyte adhesion deficiency (LAD) is a hereditary disorder caused by mutations in the CD18 (beta2 integrin) gene. Four missense mutations have been identified in three patients. CD18(A270V) supports, at a diminished level, CD11b/CD18 (Mac-1, alphaMbeta2 integrin) and CD11c/CD18 (p150,95, alphaXbeta2 integrin) expression and function but not CD11a/CD18 (LFA-1, alphaLbeta2 integrin) expression. Conversely, CD18(A341P) supports a limited level of expression and function of CD11a/CD18, but not of the other two CD11/CD18 antigens. CD18(C590R) and CD18(R593C) show a decreasing capacity to associate with the CD11a, CD11c and CD11b subunits. Transfectants expressing the CD11a/CD18 with the C590R and R593C mutations are more adhesive than transfectants expressing wild-type LFA-1, and express the reporter epitope of the monoclonal antibody 24 constitutively. Thus, the four mutations affect CD18 differently in its capacities to support CD11/CD18 expression and adhesion. These results not only provide a biochemical account for the clinical diversity of patients with leucocyte adhesion deficiency, but also offer novel insights into the structural basis of interaction between the alpha and beta subunits, which is an integral component in our understanding of integrin-mediated adhesion and its regulation.

Hematologically important mutations: leukocyte adhesion deficiency

Leukocyte adhesion deficiency (LAD) is an immunodeficiency caused by defects in the adhesion of leukocytes (especially neutrophils) to the blood vessel wall. As a result, patients with LAD suffer from severe bacterial infections and impaired wound healing. In LAD-I, mutations are found in INTG2, the gene that encodes the beta subunit of the beta(2) integrins. In the rare LAD-II disease, the fucosylation of selectin ligands is disturbed, caused by mutations in the gene for a GDP-fucose transporter of the Golgi. This article summarizes all known patient mutations and polymorphisms in these genes.

The N-terminal region and the mid-region complex of the integrin beta 2 subunit

In the primary sequence of the integrin beta subunit, the N-terminal region (NTR) and mid-region are separated by the I-like domain. To determine the spatial relationship and functional properties of the integrin beta(2) NTR and mid-region, we constructed beta(2)/beta(7) chimeras in which the NTR, I-like domain, and the mid-region of the beta(2) subunit were replaced by those of beta(7). Changing either the beta(2) NTR or mid-region, but not the I-like domain to that of beta(7) did not affect LFA-1 (alpha(L)beta(2)) formation and surface expression. Thus, the specificity of alpha(L)beta(2) pairing is conferred by the I-like domain but not the NTR or mid-region. Using these chimeras, the epitopes of six anti-beta(2) mAbs (H52, 7E4, AZN-L18, AZN-L27, KIM202, and MEM-148) were mapped. All except H52 require both the NTR and mid-region for epitope expression. Since these mAbs have distinct properties in terms of epitope expression and effect on LFA-1 binding to ICAM-1, we conclude that the beta(2) NTR and mid-region interact extensively. Although the I-like domain is located between the NTR and mid-region, its removal does not affect the folding of the beta(2) NTR/mid-region complex because this complex alone can be expressed as a soluble protein and precipitated by the appropriate mAbs. Finally, the mAbs H52 and 7E4, abrogated KIM185- but not Mg/EGTAinduced LFA-1/ICAM-1 binding and the epitope of MEM-148 is expressed on Mg/EGTA-activated but not resting LFA-1. These results suggest that the NTR/mid-region complex is involved in the regulation of LFA-1 function.

Defining the repeating elements in the cysteine-rich region (CRR) of the CD18 integrin beta 2 subunit

The cysteine-rich region (CRR) of the integrin beta subunits is organised into four repeating elements. By expression of a panel of truncated beta 2 subunits, and CRR segments fused to the C-terminal end of a CD4 soluble fragment, the segment required for the expression of two monoclonal antibody conformational epitopes was determined. This segment, E482-Q574, contains 16 cysteines representing two repeating units. We have thus defined the CRR unit motif of 'xC---C---C---CxCxxCxC---Cx', where 'x' represents a single residue, and '---' represents a stretch of four to 14 residues.

Optic disk characteristics before the occurrence of disk hemorrhage in glaucoma patients

PURPOSE

To evaluate qualitatively the structural characteristics and the associated features that antedate the occurrence of a disk hemorrhage in patients with glaucoma.

METHODS

Retrospective observational case series. A total of 4018 pairs of stereoscopic optic disk images obtained over 15 years were reviewed. All eyes with optic disk images before the occurrence of a disk hemorrhage were enrolled. The disk images were evaluated in a masked fashion with respect to the general neural rim and peripapillary appearance.

RESULTS

The optic disk characteristics and associated features that most antedate the disk hemorrhage in 33 eyes of 26 patients that had previous optic disk images for evaluation are focal neural rim notch (36%), thin sloping rim (42%), peripapillary atrophy (79%), and superior-inferior rim asymmetry (73%). In eyes with preexisting focal rim notches, all subsequent disk hemorrhages were identified at or adjacent to the notches.

CONCLUSIONS

Focal rim notching may precede the occurrence of a disk hemorrhage.

Identification of the haemoglobin scavenger receptor

Intravascular haemolysis is a physiological phenomenon as well as a severe pathological complication when accelerated in various autoimmune, infectious (such as malaria) and inherited (such as sickle cell disease) disorders. Haemoglobin released into plasma is captured by the acute phase protein haptoglobin, which is depleted from plasma during elevated haemolysis. Here we report the identification of the acute phase-regulated and signal-inducing macrophage protein, CD163, as a receptor that scavenges haemoglobin by mediating endocytosis of haptoglobin-haemoglobin complexes. CD163 binds only haptoglobin and haemoglobin in complex, which indicates the exposure of a receptor-binding neoepitope. The receptor-ligand interaction is Ca2+-dependent and of high affinity. Complexes of haemoglobin and multimeric haptoglobin (the 2-2 phenotype) exhibit higher functional affinity for CD 163 than do complexes of haemoglobin and dimeric haptoglobin (the 1-1 phenotype). Specific CD163-mediated endocytosis of haptoglobin-haemoglobin complexes is measurable in cells transfected with CD163 complementary DNA and in CD163-expressing myelo-monocytic lymphoma cells.

The effects of cysteine to alanine mutations of CD18 on the expression and adhesion of the CD11/CD18 integrins

Of the 56 cysteines in the extracellular domain of the CD18 antigen (beta2 integrin subunit), corresponding ones are not found in 12 positions in the beta4, beta7, or beta8 integrin subunits. These 12 cysteines were mutated to alanines, either singly or in pairs, in CD18. All these mutants can support the expression of all three CD11/CD18 integrins. Transfectants expressing these variant integrins are generally more adhesive than the wild-type, suggesting that the cysteine residues, perhaps by engaging in disulphide bonds, may contribute to the maintenance of the CD11/CD18 integrins in a resting state.

Effect of integrin beta 2 subunit truncations on LFA-1 (CD11a/CD18) and Mac-1 (CD11b/CD18) assembly, surface expression, and function

LFA-1 (CD11a/CD18) and Mac-1 (CD11b/CD18) are members of the beta2 integrins involved in leukocyte function during immune and inflammatory responses. We aimed to determine a minimized beta2 subunit that forms functional LFA-1 and Mac-1. Using a series of truncated beta2 variants, we showed that the subregion Q23-D300 of the beta2 subunit is sufficient to combine with the alphaL and alphaM subunits intracellularly. However, only the beta2 variants terminating after Q444 promote cell surface expression of LFA-1 and Mac-1. Thus, the major cysteine-rich region and the three highly conserved cysteine residues at positions 445, 447, and 449 of the beta2 subunit are not required for LFA-1 and Mac-1 surface expression. The surface-expressed LFA-1 variants are constitutively active with respect to ICAM-1 adhesion and these variants express the activation reporter epitope of the mAb 24. In contrast, surface-expressed Mac-1, both the wild type and variants, require 0. 5 mM MnCl2 for adhesion to denatured BSA. These results suggest that the role of the beta2 subunit in LFA-1- and Mac-1-mediated adhesion may be different.

A novel point mutation in CD18 causing the expression of dysfunctional CD11/CD18 leucocyte integrins in a patient with leucocyte adhesion deficiency (LAD)

Leucocyte adhesion deficiency type 1 (LAD-1) is characterized by the incapacity of leucocytes to carry out their adhesion functions via their CD11/CD18 antigens, which are also referred to as the leucocyte integrins. The patients generally suffer from poor wound healing and recurrent bacterial and fungal infections. In severe cases, the infections are often systemic and life-threatening. A LAD patient (AW) of moderate phenotype has been identified but, unlike most other cases, the level of CD11/CD18 antigens on her leucocytes are uncharacteristically high for a LAD patient. Molecular analysis revealed that she is a compound heterozygote for CD18 mutations. She has inherited a D231H mutation from her father and a G284S mutation from her mother. By transfection studies, it was established that the G284S mutation does not support CD11/CD18 antigen expression on the cell surface. In contrast, the D231H mutation does not affect CD18 forming integrin heterodimers with the CD11 antigens on the cell surface. However, the expressed integrins with the D231H mutation are not adhesive to ligands.

A novel leukocyte adhesion deficiency caused by expressed but nonfunctional beta2 integrins Mac-1 and LFA-1

In the leukocyte adhesion deficiency (LAD)-1 syndrome, there is diminished expression of beta2(CD18) integrins. This is caused by lesions in the beta2-subunit gene and gives rise to recurrent bacterial infections, impaired pus formation, and poor wound healing. We describe a patient with clinical features compatible with a moderately severe phenotype of LAD-1 but who expresses the beta2 integrins lymphocyte function- associated molecule (LFA)-1 and Mac-1 at 40%-60% of normal levels. This level of expression should be adequate for normal integrin function, but both the patient's Mac-1 on neutrophils and LFA-1 on T cells failed to bind ligands such as fibrinogen and intercellular adhesion molecule (ICAM)-1, respectively, or to display a beta2-integrin activation epitope after adhesion-inducing stimuli. Unexpectedly, divalent cation treatment induced the patient's T cells to bind to ICAM-2 and ICAM-3. Sequencing of the patient's two CD18 alleles revealed the mutations S138P and G273R. Both mutations are in the beta2-subunit conserved domain, with S138P a putative divalent cation coordinating residue in the metal ion-dependent adhesion site (MIDAS) motif. After K562 cell transfection with alpha subunits, the mutated S138P beta subunit was coexpressed but did not support function, whereas the G273R mutant was not expressed. In summary, the patient described here exhibits failure of the beta2 integrins to function despite adequate levels of cell-surface expression.