Persistent polyclonal B-cell lymphocytosis: a case report

Histopathological and molecular features of persistent polyclonal B‐cell lymphocytosis (PPBL) with progressive splenomegaly

“…We report on the occurrence of progressive splenomegaly after two or more years from diagnosis, in five PPBL cases. This observation is intriguing, since only two PBBL cases with a concomitant or subsequent malignant lymphoma have been reported out of a hundred described (de Haan & Pouwels, 2006) since the first report (Gordon et al, 1982), but none of them documented a correlation between the two conditions , supporting the notion of the benign course of this condition. More recently, in the largest series of PPBL reporting a long-term follow-up (median 4AE4 years, range: 0AE5-29) (Cornet et al, 2008), only three of 111 patients developed a high-or low-grade lymphoma.…”

Anticipatory plastic response of the cellular immune system in the face of future injury: chronic high perceived predation risk induces lymphocytosis in a cichlid fish

“…As basophils, eosinophils, and precursors were very rare (found to be present in only 11.24%, 1.24%, and 0% of all blood smears, respectively and equally distributed across treatments), we excluded them from our analysis. From these relative values, absolute blood counts were then calculated for each individual fish as well as the proportion of neutrophils:lymphocytes as this ratio is suggested to be a reliable indicator of stress (Davis et al 2008). Peripheral blood smears were stained by May-Grünwald-Giemsa (Pappenheim stain).…”

“…Fish hematology has a long history (Hesser 1960;Blaxhall and Daisley 1973), and this is why, fish are a well-studied, non-human vertebrate group in terms of their leukocyte responses (Davis et al 2008;Burgos-Aceves et al 2019). Ichthyologists consider fish leukocyte responses one of the most sensitive indicators of stress (Wedemeyer et al 1990).…”

“…Even when there is mention of a chronic exposure protocol, this refers to a period of no more than up to 9 weeks and a 9-week exposure period was only applied in a single study (Johansson-Sjöbeck and Larsson 1978). However, because fish are ectothermic, the time course of fish leukocyte patterns is lengthy (Davis et al 2008), and hence, they reflect long-term stress more accurately than short-term stress as directly shown in a study with the channel catfish Ictalurus punctatus (Bly et al 1990). Hence, there is a clear need for more long-term research to understand patterns of phenotypic plasticity in fish leukocytes.…”

“…Therefore, hematology, the study of blood, was developed since the 1920s as a valuable and highly informative medical diagnostic tool (Wintrobe et al 1974). Researchers have since used differential leukocyte counts for studying variation in wildlife immune responses (Davis et al 2008), but this variation is still not fully understood (Maceda-Veiga et al 2015). Most previous studies have been conducted in a medical, toxicological, and animal ethics context, and thus focus on the consequences of exposure to environmental factors that disturb physical integrity such as toxins (Eeva et al 2005;Villa et al 2017), parasites, and pathogens (Davis et al 2004;Lobato et al 2005;Burnham et al 2006), suboptimal nutrition, temperature, or humidity levels (Bennett and Daigle 1983;Altan et al 2000;Brown and Shine 2018; Communicated by Donovan P German.…”