Adaptation and Reach of a Pre-Exposure Prophylaxis Social Marketing Campaign for Latino, Latina, and Latinx Populations: Development Study.

BACKGROUND: Latino, Latina, and Latinx (Latino/a/x) individuals remain disproportionately impacted by HIV, particularly sexual minority men and transgender women. Pre-exposure prophylaxis (PrEP) is an effective means of biomedical HIV prevention, but awareness and uptake remain low among marginalized Latino/a/x populations. Social marketing campaigns have demonstrated promise in promoting PrEP in other populations but are poorly studied in Latino/a/x sexual minority men and transgender women. OBJECTIVE: This study aims to (1) adapt and pilot a PrEP social marketing campaign tailored to Latino/a/x populations with a focus on sexual minority men and transgender women through community-based participatory research (CBPR) and (2) evaluate the reach and ad performance of the adapted PrEP social marketing campaign. METHODS: We used the ADAPT-ITT (assessment, decision, adaptation, production, topical experts-integration, training, and testing) framework for adapting evidence-based interventions for new settings or populations. This paper presents how each phase of the ADAPT-ITT framework was applied via CBPR to create the PrEPárate ("Be PrEPared") campaign. Key community engagement strategies included shared ownership with community partners, focus groups to guide content, crowdsourcing to name the campaign, design by local Latino/a/x artists, and featuring local influencers as the faces of PrEPárate. We evaluated campaign reach and advertisement performance using social media platform metrics (paid and organic reach, impressions, unique clicks, and click-through rates [CTR]) and website use statistics from Google Analytics. RESULTS: The PrEPárate campaign ran in Cook County, Illinois, from April to September 2022. The campaign reached over 118,750 people on social media (55,750 on Facebook and Instagram [Meta Platforms Inc] and 63,000 on TikTok [ByteDance Ltd]). The Meta ads performed over the industry benchmark with ads featuring local transgender women (2% CTR) and cisgender sexual minority men (1.4% CTR). Of the different Grindr (Grindr Inc) ad formats piloted, the interstitial Grindr ads were the highest performing (1183/55,479, 2.13% CTR). YouTube (Google) ads were low performing at 0.11% (153/138,337) CTR and were stopped prematurely, given limits on sexual education-related content. In the first year, there were 5006 visitors to the website. CONCLUSIONS: Adaptation of an existing evidence-based intervention served as an effective method for developing a PrEP social marketing campaign for Latino/a/x audiences. CBPR and strong community partnerships were essential to tailor materials and provide avenues to systematically address barriers to PrEP access. Social marketing is a promising strategy to promote PrEP among underserved Latino/a/x populations.

A Community-Engaged Social Marketing Campaign to Promote Equitable Access to COVID-19 Services Among Latino Immigrants.

To address disparities in COVID-19 outcomes among Latinos with limited English proficiency in Maryland, our team developed a culturally congruent intervention that coupled a statewide social marketing campaign with community-based COVID-19 services. In the first year, we reached 305 122 people through social media advertisements and had 9607 visitors to the Web site. Social marketing campaigns represent an opportunity to promote COVID-19 testing and vaccine uptake among Latino populations, especially when they are paired with community services that simultaneously address structural barriers to care. (Am J Public Health. 2023;113(3):263-266. https://doi.org/10.2105/10.2105/AJPH.2022.307191).

Study protocol: Behavioral economics and self-determination theory to change diabetes risk (BEST Change).

BACKGROUND: The Diabetes Prevention Program (DPP) and metformin can prevent or delay the onset of type 2 diabetes mellitus (T2DM) among patients with prediabetes. Yet, even when these evidence-based strategies are accessible and affordable, uptake is low. Thus, there is a critical need for effective, scalable, and sustainable approaches to increase uptake and engagement in these interventions. METHODS: In this randomized controlled trial, we will test whether financial incentives and automated messaging to promote autonomous motivation for preventing T2DM can increase DPP participation, metformin use, or both among adults with prediabetes. Participants (n = 380) will be randomized to one of four study arms. Control Arm participants will receive usual care and educational text messages about preventing T2DM. Incentives Arm participants will receive the Control Arm intervention plus financial incentives for DPP participation or metformin use. Tailored Messages Arm participants will receive the Control Arm intervention plus tailored messages promoting autonomous motivation for preventing T2DM. Combined Arm participants will receive the Incentives Arm and Tailored Messages Arm interventions plus messages to increase the personal salience of financial incentives. The primary outcome is change in hemoglobin A1c from baseline to 12 months. Secondary outcomes are change in body weight, DPP participation, and metformin use. DISCUSSION: If effective, these scalable and sustainable approaches to increase patient motivation to prevent T2DM can be deployed by health systems, health plans, and employers to help individuals with prediabetes lower their risk for developing T2DM.

HIV-related stigma among Spanish-speaking Latinos in an emerging immigrant city following the Solo Se Vive Una Vez social marketing campaign.

HIV-related stigma exacerbates Latino immigrants' risk of HIV infection and delayed care. Following the implementation of the social marketing campaign Sólo Se Vive Una Vez (You Only Live Once) to increase HIV testing that addressed stigmatizing beliefs, we conducted a survey among Latinos in Baltimore, Maryland (N = 357). The aims of this paper are to 1) characterize the sociodemographic characteristics, HIV-related stigma beliefs, and testing behaviors of the survey respondents by campaign exposure, and 2) model the effects of Vive exposure on stigma beliefs and testing behaviors. Comparing post-campaign survey respondents exposed and unexposed to the campaign to survey findings previously obtained and reported before the campaign implementation, respondents to the post-Vive survey continued to hold high levels of stigma beliefs, and compared to the pre-Vive survey sample, were more likely to hold four or more stigmatizing beliefs (from the six survey items). Among the post-Vive survey respondents, those for whom religion was important or very important had an increased odds of 1.6 of holding four or more stigmatizing beliefs. Survey respondents who were exposed to the campaign, however, had an increased odds of 2.25 of reporting ever having been tested for HIV. Our findings demonstrate the importance of the changing social context in addressing stigma within emerging immigrant communities and highlight the critical role of religious leaders in efforts to address HIV-related stigma.

A Crowdsourcing Open Contest to Design a Latino-Specific COVID-19 Campaign: Mixed Methods Analysis.

BACKGROUND: Latino communities are among the most heavily impacted populations by the COVID-19 pandemic in the United States due to intersectional barriers to care. Crowdsourcing open contests can be an effective means of community engagement but have not been well studied in Latino populations nor in addressing the COVID-19 pandemic. OBJECTIVE: The aims of this study are to (1) implement and evaluate a crowdsourcing open contest to solicit a name for a COVID-19 social marketing campaign for Latino populations in Maryland and (2) conduct a thematic analysis of submitted entries to guide campaign messaging. METHODS: To assess the level of community engagement in this crowdsourcing open contest, we used descriptive statistics to analyze data on entries, votes, and demographic characteristics of participants. The submitted text was analyzed through inductive thematic analysis. RESULTS: We received 74 entries within a 2-week period. The top 10 entries were chosen by community judges and the winner was decided by popular vote. We received 383 votes within 1 week. The most common themes were collective efficacy, self-efficacy, and perceived benefits of COVID-19 testing. We used these themes to directly inform our social marketing intervention and found that advertisements based on these themes became the highest performing. CONCLUSIONS: Crowdsourcing open contests are an effective means of community engagement and an agile tool for guiding interventions to address COVID-19, including in populations impacted by health care disparities, such as Latino communities. The thematic analysis of contest entries can be a valuable strategy to inform the development of social marketing campaign materials.

Cumulative Genetic Risk and APOE ε4 Are Independently Associated With Dementia Status in a Multiethnic, Population-Based Cohort.

OBJECTIVE: Alzheimer disease (AD) is a common and costly neurodegenerative disorder. A large proportion of AD risk is heritable, and many genetic risk factors have been identified. The objective of this study was to test the hypothesis that cumulative genetic risk of known AD markers contributed to odds of dementia in a population-based sample. METHODS: In the US population-based Health and Retirement Study (waves 1995-2014), we evaluated the role of cumulative genetic risk of AD, with and without the APOE ε4 alleles, on dementia status (dementia, cognitive impairment without dementia, borderline cognitive impairment without dementia, and cognitively normal). We used logistic regression, accounting for demographic covariates and genetic principal components, and analyses were stratified by European and African genetic ancestry. RESULTS: In the European ancestry sample (n = 8,399), both AD polygenic score excluding the APOE genetic region (odds ratio [OR] = 1.10; 95% confidence interval [CI]: 1.00-1.20) and the presence of any APOE ε4 alleles (OR = 2.42; 95% CI: 1.99-2.95) were associated with the odds of dementia relative to normal cognition in a mutually adjusted model. In the African ancestry sample (n = 1,605), the presence of any APOE ε4 alleles was associated with 1.77 (95% CI: 1.20-2.61) times higher odds of dementia, whereas the AD polygenic score excluding the APOE genetic region was not significantly associated with the odds of dementia relative to normal cognition 1.06 (95% CI: 0.97-1.30). CONCLUSIONS: Cumulative genetic risk of AD and APOE ε4 are both independent predictors of dementia in European ancestry. This study provides important insight into the polygenic nature of dementia and demonstrates the utility of polygenic scores in dementia research.

Sólo Se Vive Una Vez: Evaluation of a Social Marketing Campaign Promoting HIV Screening and Prevention for Immigrant Latinxs.

Latinxs in the U.S. are disproportionately affected by HIV and more likely to have delayed diagnosis than their non-Latinx peers. We developed and implemented Sólo Se Vive Una Vez (You Only Live Once), the first Spanish-language campaign aimed at improving HIV testing and prevention among Latinx immigrants in Baltimore, Maryland. Sólo Se Vive Una Vez featured a website ( www.solovive.org ) and social marketing campaign promoting free HIV testing through the Baltimore City Health Department (BCHD) clinic and Latinx outreach team. The campaign was not associated with a change in the overall number of Latinxs obtaining HIV testing. However, Latinx HIV testers who reported being exposed to the campaign had significantly higher rates of high-risk sexual behaviors, mean number of sexual partners, and substance use. The campaign was also associated with increased PrEP referrals through the BCHD Latinx outreach team.

RESUMEN: Los latinos en los Estados Unidos están desproporcionadamente afectados por el VIH y es más probable que sean diagnosticados más tarde que pacientes no latinos. Desarrollamos e implementamos Sólo Se Vive Una Vez, la primera campaña en español dirigida a mejorar la detección y prevención del VIH entre los inmigrantes latinos en Baltimore, Maryland. Sólo Se Vive Una Vez consiste en un sitio web (www.solovive.org) y una campaña en las redes sociales que promueve la prueba gratuita de VIH a través de la clínica del Departamento de Salud de la Ciudad de Baltimore así como la unidad móvil operada por nuestro equipo latino de promotores de salud. La campaña no se asoció con un cambio en el número absoluto de latinos que hicieron la prueba del VIH. Sin embargo, los latinos expuestos a la campaña que se hicieron la prueba del VIH tenían tasas más altas de conductas sexuales de alto riesgo, de parejas sexuales, y de uso de sustancias. La campaña también se asoció con un aumento de referidos a PrEP a través del equipo de promotores de salud latinos.

Sólo Se Vive Una Vez: The Implementation and Reach of an HIV Screening Campaign for Latinx Immigrants.

Latinxs in the United States are disproportionately affected by HIV and present with more advanced disease than their non-Latinx peers, due to numerous barriers to care including HIV stigma. We describe the adaptation, implementation, and reach of Sólo Se Vive Una Vez (You Only Live Once), Baltimore's first social marketing campaign promoting HIV screening among Spanish-speaking Latinxs. The 6-month campaign promoted free HIV testing by addressing HIV stigma. The campaign included a website, a social marketing campaign, community outreach events, and advertisements via radio, billboards, local partners, and buses. During the campaign, there were 9,784 unique website users, and ads were served to over 84,592 people on social media platforms. Among Latinx HIV testers at the Baltimore City Health Department, 31.6% reported having seen or heard of Sólo Se Vive Una Vez and 25.3% of Latinx HIV testers reported that the campaign influenced them to get tested.

Heavy Metals Exposure and Alzheimer's Disease and Related Dementias.

Alzheimer's disease and related dementias lack effective treatment or cures and are major public health challenges. Risk for Alzheimer's disease and related dementias is partially attributable to environmental factors. The heavy metals lead, cadmium, and manganese are widespread and persistent in our environments. Once persons are exposed to these metals, they are adept at entering cells and reaching the brain. Lead and cadmium are associated with numerous health outcomes even at low levels of exposure. Although manganese is an essential metal, deficiency or environmental exposure or high levels of the metal can be toxic. In cell and animal model systems, lead, cadmium, and manganese are well documented neurotoxicants that contribute to canonical Alzheimer's disease pathologies. Adult human epidemiologic studies have consistently shown lead, cadmium, and manganese are associated with impaired cognitive function and cognitive decline. No longitudinal human epidemiology study has assessed lead or manganese exposure on Alzheimer's disease specifically though two studies have reported a link between cadmium and Alzheimer's disease mortality. More longitudinal epidemiologic studies with high-quality time course exposure data and incident cases of Alzheimer's disease and related dementias are warranted to confirm and estimate the proportion of risk attributable to these exposures. Given the widespread and global exposure to lead, cadmium, and manganese, even small increases in the risks of Alzheimer's disease and related dementias would have a major population impact on the burden on disease. This article reviews the experimental and epidemiologic literature of the associations between lead, cadmium, and manganese on Alzheimer's disease and related dementias and makes recommendations of critical areas of future investment.

Safety and efficacy of PD-1/PD-L1 blockade in patients with preexisting antinuclear antibodies.

PURPOSE: Immune checkpoint inhibitors (ICIs) show promising clinical activity in advanced cancers. However, the safety and efficacy of PD-1/PD-L1 blockade in patients with preexisting antinuclear antibodies (ANA) are unclear. METHODS: 191 patients treated with nivolumab, pembrolizumab, atezolizumab, or durvalumab for unresectable advanced cancers between September 2014 and December 2018 were identified retrospectively. Patients were divided into positive (ANA titers ≥ 1:160) and negative ANA groups (ANA titers < 1:160). Development of immune-related adverse events (irAEs), the overall response rate (ORR), and disease control rate (DCR) were monitored. RESULTS: Positive ANA titers were seen in 9 out of 191 patients. Four patients in the positive ANA group and 69 patients in the negative group developed irAEs of any grade without a significant difference between the groups. The development of endocrine, pulmonary, and cutaneous irAEs was not significant, whereas positive ANA was significantly higher in patients who developed colitis (2/9) than in patients who did not (3/182, P = 0.0002). DCR in the positive and negative ANA group was 37.5% and 67.5%, respectively, and was not statistically significant, but had better efficacy in patients without ANA (P = 0.08). ANA-related autoimmune diseases such as SLE, Sjögren's syndrome, MCTD, scleroderma, dermatomyositis, and polymyositis was not induced in either group. However, one patient with preexisting dermatomyositis had a flare up after initiation of atezolizumab. CONCLUSION: Further studies to identify predictive factors for the development of irAEs are required to provide relevant patient care and maximize the therapeutic benefits of ICIs.

Are Parent Activation and Health Literacy Distinct Concepts? A Study in Low Income Urban Populations.

Patient activation (the knowledge, confidence, willingness, and skills to manage one's healthcare) and health literacy have well-established associations with health and healthcare outcomes in adults. However, little is known about parent activation on behalf of children and its relation to health literacy. Our objective was to examine relations between parent activation, health literacy, and parent-provider relationship quality. We surveyed 316 Spanish- or English-speaking parents of publicly-insured patients of a general pediatrics clinic. Surveys included the Parent-Patient Activation Measure (P-PAM), the Newest Vital Sign (NVS), and parent-provider relationship measures. We used chi-square analyses and logistic regression to explore associations stratified by survey language. Spanish-speaking parents had significantly lower levels of both parent activation and health literacy compared with English-speaking parents (p<.001). Parent activation was not associated with health literacy, suggesting that they are distinct concepts. Because parent activation is a more easily modifiable trait than health literacy, it may present an opportunity to improve outcomes in less health literate populations. We did not find expected associations between parent activation, health literacy and parent-provider relationship quality. Further study is needed to understand how parent activation relates to pediatric outcomes, and if it is an appropriate intervention target to address child healthcare disparities in populations with limited health literacy.

Effect of long-term and low-dose administration of erythromycin on proliferation of T lymphocytes stimulated with mitogens.

The aim of the study was to assess the effect of long-term low-dose erythromycin (EM) treatment for chronic airway inflammation on proliferation of T cell subsets when stimulated with concanavalin A (Con A) and phytohemagglutinin (PHA). CD8+ cells are much more responsive to Con A compared to PHA. Ten patients with bronchiectasis were administered EM at 400 mg daily for 6 months. The extent of proliferation was assayed by [(3)H] thymidine incorporation and expressed as a stimulation index (SI). The lymphocyte subsets were analyzed including CD3+, CD4+ and CD8+ cells. The SI stimulated with Con A in the last month of therapy was significantly lower compared with that before the start of therapy (p=0.015) and 3 months after the end of therapy (p=0.002). However, EM therapy did not make a significant difference to the SIs when stimulated with PHA. CD3+, CD4+ and CD8+ cells in absolute numbers and CD4+/CD8+ ratios were not different among those harvested at the three time points. Long-term administration of EM may decrease the transformation response of CD8+ cells in patients.

Continued gefitinib treatment after disease stabilisation prolongs survival of Japanese patients with non-small-cell lung cancer: Okayama Lung Cancer Study Group experience.

BACKGROUND: This study aimed to investigate the survival outcome of patients with non-small-cell lung cancer (NSCLC) who had obtained disease stabilisation with gefitinib treatment and to clarify the effect of continued treatment with gefitinib on prognosis. PATIENTS AND METHODS: We reviewed the clinical records of 365 Japanese patients with NSCLC who received gefitinib (250 mg/day). RESULTS: Of 324 (89%) patients assessable for response, 147 (45%) obtained disease stabilisation and 71 (22%) patients achieved an objective response. Overall survival in patients obtaining disease stabilisation was significantly longer than in patients with progressive disease (median survival time 12.1 versus 4.4 months; P <0.0001). In patients obtaining disease stabilisation, those who continued gefitinib treatment until disease progression tended to have longer overall and progression-free survival compared with those discontinuing gefitinib treatment (1-year survival rate 52.1% versus 36.6%, P = 0.08; 1-year progression-free survival rate 31.8% versus 5.2%, P = 0.001). Multivariate analysis showed discontinuing gefitinib was an independent risk factor for progression-free survival (hazard ratio 1.66; 95% confidence interval 1.07-2.56; P = 0.022) but not for overall survival. CONCLUSIONS: Our findings indicate the importance of achieving disease stabilisation with gefitinib treatment and continued gefitinib treatment in Japanese patients with disease stabilisation, although further studies are required to confirm these findings.

Phase I/II study of docetaxel and cisplatin with concurrent thoracic radiation therapy for locally advanced non-small-cell lung cancer.

Recent studies have suggested the superiority of concomitant over sequential administration of chemotherapy and radiotherapy. Docetaxel and cisplatin have demonstrated efficacy in advanced non-small-cell lung cancer (NSCLC). This study evaluated the safety, toxicity, and antitumour activity of docetaxel/cisplatin with concurrent thoracic radiotherapy for patients with locally advanced NSCLC. Patients with locally advanced NSCLC (stage IIIA or IIIB), good performance status, age or=3 toxicities of 71, 60, 24, and 19%, respectively. Toxicity was significant, but manageable according to the dose and schedule modifications. Dose intensities of docetaxel and cisplatin were 86 and 87%, respectively. Radiotherapy was completed without a delay in 67% of 42 patients. The overall response rate was 79% (95% confidence interval (CI), 66-91%). The median survival time was 23.4+ months with an overall survival rate of 76% at 1 year and 54% at 2 years. In conclusion, chemotherapy with cisplatin plus docetaxel given on days 1, 8, 29, and 36 and concurrent thoracic radiotherapy is efficacious and tolerated in patients with locally advanced NSCLC and should be evaluated in a phase III study.

Fractionated administration of irinotecan and cisplatin for treatment of non-small-cell lung cancer: a phase II study of Okayama Lung Cancer Study Group.

A phase II study of fractionated administration of irinotecan (CPT-11) and cisplatin (CDDP) in patients with non-small-cell lung cancer (NSCLC) was conducted. Between January 1996 and January 1998, 44 previously untreated patients with stage IIIB or IV NSCLC were enrolled. CDDP at a dose of 60 mg x m(-2) was given first and followed by CPT-11 at a dose of 50 mg x m(-2). Both drugs were given by 1-hour infusion on days 1 and 8, and repeated every 4 weeks up to 4 cycles. 42 patients were evaluated for response and 44 for survival and toxicity. 20 patients (48%: 95% confidence interval 32-63%) achieved an objective response. The median duration of responses was 8 months, and the median survival time and the 1-year survival rate were 12.5 months and 56.8%, respectively. Major toxicities were neutropenia and diarrhoea. Grade 3 or 4 neutropenia occurred in 70.5% of the patients and one patient died of sepsis. Grade 3 or 4 diarrhoea was experienced in 25.0%, but manageable by conventional therapy. In conclusion, fractionated administration of CPT-11 and CDDP was highly effective for advanced NSCLC with manageable toxicities.

[Acute eosinophilic pneumonia with diffuse fine nodular shadows].

A 45-year-old man was admitted to our hospital because of high fever, dry cough, and respiratory distress. Chest roentgenograms and computed tomograms showed diffuse fine nodular shadows without any other interstitial or alveolar infiltrates. An examination of transbronchial lung biopsy specimens disclosed infiltration of eosinophils and lymphocytes in alveolar walls and perivascular areas. Bronchoalveolar lavage fluid revealed elevated total cell counts, mostly of eosinophils and lymphocytes. The patient was given a diagnosis of acute eosinophilic pneumonia (AEP), but his symptoms improved in a week without any medication. Although diffuse fine nodular shadows on x-ray films may sometimes be the only sign of AEP.

Macrophage-chemotactic factor-producing T cell hybridomas reactive to phosphorylcholine in I-E-restricted manner.

Macrophage-chemotactic factor (MChF)-producing T cell hybridomas were established. These hybridomas produced MChF upon the specific antigenic stimulation with phosphorylcholine (PC)-conjugated protein in the presence of I-Ed-positive antigen-presenting cells. The hybridomas also secreted MChF after co-culture with concanavalin A in the absence of antigen-presenting cells. The MChF-secreting hybridomas were positive for Kd, Dd, Lyt-1.2 but negative for I-Ad, Lyt-2.2. The molecular weight of MChF produced by the hybridomas was 43000 and the factor was focused at pH 6.6-6.8 in the chromatofocusing procedure. The MChF was protease sensitive but resistant to neuraminidase treatment, and it was stable by heating at 80 degrees C for 15 min. The MChF-producing hybridomas established in this stud did not produce macrophage migration inhibitory factor (MIF), macrophage-activating factor (MAF) or interleukin 2, suggesting molecular nonidentity between MChF and these lymphokines. The MChF-producing T cell hybridomas reactive to specific antigens (PC) will be promising tools for analysis of molecular nature of MChF as well as molecular aspects of antigen recognition mechanism of T cells.

Lymphocyte chemotaxis in inflammation. VIII. Demonstration of lymphocyte chemotactic lymphokines in PPD-induced delayed hypersensitivity skin reaction site in the guinea-pig.

The experiments were carried out to clarify whether lymphocyte chemotactic factors (LCFs) derived from activated lymphocytes, i.e. lymphocyte chemotactic lymphokines would exist in delayed-type hypersensitivity (DTH) reaction sites in guinea-pigs. To analyse the problem, we attempted to use an immunoadsorbent column conjugated with respective antibodies against LCFs (LCF-b, LCF-c and LCF-d) isolated from purified protein derivative (PPD)-induced DTH skin reaction sites in guinea-pigs. The chemotactic activity of culture supernatants from PPD- or concanavalin A (Con A)-stimulated lymph node (LN) cells was decreased to about 50% by the immunoadsorbent column with anti-LCF-c antibody or anti-LCF-d antibody, while its activity was little or not influenced by the columns with anti-LCF-b, anti-IgG or anti-IgM antibody. Further experiments using successive immunoadsorption with anti-LCF-c antibody followed by anti-LCF-d antibody showed almost the complete adsorption of the chemotactic activity in the above culture fluids. Additionally, the chemotactic lymphokine which was absorbed by anti-LCF-c antibody had a similar mol. wt. to that of LCF-c (mol. wt about 160,000). However, the chemotactic lymphokine which was absorbed by anti-LCF-d antibody had a mol. wt. of about 27,000; it was clearly distinct in mol. wt. from LCF-d (mol. wt. about 300,000). It is thus suggested that at least one of lymphocyte chemotactic lymphokines exists in the DTH reaction sites and functions as LCF-c.

Lymphocyte chemotaxis in inflammation. VII. Isolation and purification of chemotactic factors for T lymphocytes from PPD-induced delayed hypersensitivity skin reaction site in the guinea-pig.

Four types of lymphocyte chemotactic factor (LCF-a, -b, -c and -d) could be isolated from extract of 24-hr-old delayed-type hypersensitivity (DTH) skin reaction sites induced with purified protein derivative (PPD) in guinea-pigs by gel filtration on Sephadex G-100 followed by chromatography with DEAE-Sephadex. Partially purified LCF-b was thought to be a heat-stable protein with a molecular weight (mol. wt.) of about 14,000. LCF-c separated from LCF-d by chromatography with DEAE-Sephadex was highly purified by chromatography with CM-Sephadex, immunoadsorbent chromatography coupled with anti-IgG antibody, and chromatofocusing in that order. It was considered to be a heat-labile protein with a mol. wt. of about 160,000 and with pI of 8.1 +/- 0.2. LCF-d first separated from LCF-c was also highly purified by chromatography with CM-Sephadex followed by preparative isotachophoresis. The factor was considered to be a heat-labile protein with a mol. wt. of approximately 300,000 and with pI of 6.2 +/- 0.2. These factors were similarly active for non-adherent cells (mostly T cells) but not for cells (mostly B cells) adherent to anti-IgG antibody-coated petri-dishes. Since LCF-a was active for B cells as described earlier, it is thus suggested that LCF-b, LCF-c and LCF-d may be important for T cell migration in the DTH site to PPD.